5805040d28
Fixes 6069 Calling `item.ident.as_str()` returns an NFC normalized ident, which might not be what's written in the source code. To avoid panics when calling `snippet_provider.span_after` use the ident from the source.
3479 lines
117 KiB
Rust
3479 lines
117 KiB
Rust
// Formatting top-level items - functions, structs, enums, traits, impls.
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use std::borrow::Cow;
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use std::cmp::{max, min, Ordering};
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use regex::Regex;
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use rustc_ast::visit;
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use rustc_ast::{ast, ptr};
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use rustc_span::{symbol, BytePos, Span, DUMMY_SP};
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use crate::attr::filter_inline_attrs;
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use crate::comment::{
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combine_strs_with_missing_comments, contains_comment, is_last_comment_block,
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recover_comment_removed, recover_missing_comment_in_span, rewrite_missing_comment,
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FindUncommented,
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};
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use crate::config::lists::*;
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use crate::config::{BraceStyle, Config, IndentStyle, Version};
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use crate::expr::{
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is_empty_block, is_simple_block_stmt, rewrite_assign_rhs, rewrite_assign_rhs_with,
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rewrite_assign_rhs_with_comments, rewrite_else_kw_with_comments, rewrite_let_else_block,
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RhsAssignKind, RhsTactics,
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};
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use crate::lists::{definitive_tactic, itemize_list, write_list, ListFormatting, Separator};
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use crate::macros::{rewrite_macro, MacroPosition};
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use crate::overflow;
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use crate::rewrite::{Rewrite, RewriteContext};
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use crate::shape::{Indent, Shape};
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use crate::source_map::{LineRangeUtils, SpanUtils};
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use crate::spanned::Spanned;
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use crate::stmt::Stmt;
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use crate::types::opaque_ty;
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use crate::utils::*;
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use crate::vertical::rewrite_with_alignment;
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use crate::visitor::FmtVisitor;
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const DEFAULT_VISIBILITY: ast::Visibility = ast::Visibility {
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kind: ast::VisibilityKind::Inherited,
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span: DUMMY_SP,
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tokens: None,
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};
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fn type_annotation_separator(config: &Config) -> &str {
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colon_spaces(config)
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}
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// Statements of the form
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// let pat: ty = init; or let pat: ty = init else { .. };
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impl Rewrite for ast::Local {
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fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
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debug!(
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"Local::rewrite {:?} {} {:?}",
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self, shape.width, shape.indent
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);
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skip_out_of_file_lines_range!(context, self.span);
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if contains_skip(&self.attrs) {
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return None;
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}
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let attrs_str = self.attrs.rewrite(context, shape)?;
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let mut result = if attrs_str.is_empty() {
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"let ".to_owned()
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} else {
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combine_strs_with_missing_comments(
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context,
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&attrs_str,
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"let ",
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mk_sp(
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self.attrs.last().map(|a| a.span.hi()).unwrap(),
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self.span.lo(),
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),
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shape,
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false,
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)?
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};
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let let_kw_offset = result.len() - "let ".len();
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// 4 = "let ".len()
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let pat_shape = shape.offset_left(4)?;
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// 1 = ;
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let pat_shape = pat_shape.sub_width(1)?;
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let pat_str = self.pat.rewrite(context, pat_shape)?;
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result.push_str(&pat_str);
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// String that is placed within the assignment pattern and expression.
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let infix = {
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let mut infix = String::with_capacity(32);
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if let Some(ref ty) = self.ty {
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let separator = type_annotation_separator(context.config);
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let ty_shape = if pat_str.contains('\n') {
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shape.with_max_width(context.config)
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} else {
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shape
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}
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.offset_left(last_line_width(&result) + separator.len())?
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// 2 = ` =`
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.sub_width(2)?;
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let rewrite = ty.rewrite(context, ty_shape)?;
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infix.push_str(separator);
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infix.push_str(&rewrite);
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}
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if self.kind.init().is_some() {
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infix.push_str(" =");
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}
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infix
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};
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result.push_str(&infix);
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if let Some((init, else_block)) = self.kind.init_else_opt() {
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// 1 = trailing semicolon;
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let nested_shape = shape.sub_width(1)?;
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result = rewrite_assign_rhs(
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context,
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result,
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init,
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&RhsAssignKind::Expr(&init.kind, init.span),
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nested_shape,
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)?;
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if let Some(block) = else_block {
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let else_kw_span = init.span.between(block.span);
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// Strip attributes and comments to check if newline is needed before the else
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// keyword from the initializer part. (#5901)
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let init_str = if context.config.version() == Version::Two {
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&result[let_kw_offset..]
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} else {
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result.as_str()
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};
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let force_newline_else = pat_str.contains('\n')
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|| !same_line_else_kw_and_brace(init_str, context, else_kw_span, nested_shape);
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let else_kw = rewrite_else_kw_with_comments(
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force_newline_else,
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true,
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context,
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else_kw_span,
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shape,
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);
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result.push_str(&else_kw);
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// At this point we've written `let {pat} = {expr} else' into the buffer, and we
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// want to calculate up front if there's room to write the divergent block on the
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// same line. The available space varies based on indentation so we clamp the width
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// on the smaller of `shape.width` and `single_line_let_else_max_width`.
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let max_width =
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std::cmp::min(shape.width, context.config.single_line_let_else_max_width());
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// If available_space hits zero we know for sure this will be a multi-lined block
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let assign_str_with_else_kw = if context.config.version() == Version::Two {
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&result[let_kw_offset..]
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} else {
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result.as_str()
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};
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let available_space = max_width.saturating_sub(assign_str_with_else_kw.len());
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let allow_single_line = !force_newline_else
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&& available_space > 0
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&& allow_single_line_let_else_block(assign_str_with_else_kw, block);
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let mut rw_else_block =
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rewrite_let_else_block(block, allow_single_line, context, shape)?;
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let single_line_else = !rw_else_block.contains('\n');
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// +1 for the trailing `;`
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let else_block_exceeds_width = rw_else_block.len() + 1 > available_space;
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if allow_single_line && single_line_else && else_block_exceeds_width {
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// writing this on one line would exceed the available width
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// so rewrite the else block over multiple lines.
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rw_else_block = rewrite_let_else_block(block, false, context, shape)?;
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}
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result.push_str(&rw_else_block);
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};
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}
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result.push(';');
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Some(result)
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}
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}
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/// When the initializer expression is multi-lined, then the else keyword and opening brace of the
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/// block ( i.e. "else {") should be put on the same line as the end of the initializer expression
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/// if all the following are true:
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///
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/// 1. The initializer expression ends with one or more closing parentheses, square brackets,
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/// or braces
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/// 2. There is nothing else on that line
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/// 3. That line is not indented beyond the indent on the first line of the let keyword
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fn same_line_else_kw_and_brace(
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init_str: &str,
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context: &RewriteContext<'_>,
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else_kw_span: Span,
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init_shape: Shape,
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) -> bool {
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if !init_str.contains('\n') {
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// initializer expression is single lined. The "else {" can only be placed on the same line
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// as the initializer expression if there is enough room for it.
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// 7 = ` else {`
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return init_shape.width.saturating_sub(init_str.len()) >= 7;
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}
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// 1. The initializer expression ends with one or more `)`, `]`, `}`.
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if !init_str.ends_with([')', ']', '}']) {
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return false;
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}
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// 2. There is nothing else on that line
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// For example, there are no comments
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let else_kw_snippet = context.snippet(else_kw_span).trim();
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if else_kw_snippet != "else" {
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return false;
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}
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// 3. The last line of the initializer expression is not indented beyond the `let` keyword
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let indent = init_shape.indent.to_string(context.config);
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init_str
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.lines()
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.last()
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.expect("initializer expression is multi-lined")
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.strip_prefix(indent.as_ref())
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.map_or(false, |l| !l.starts_with(char::is_whitespace))
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}
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fn allow_single_line_let_else_block(result: &str, block: &ast::Block) -> bool {
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if result.contains('\n') {
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return false;
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}
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if block.stmts.len() <= 1 {
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return true;
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}
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false
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}
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// FIXME convert to using rewrite style rather than visitor
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// FIXME format modules in this style
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#[allow(dead_code)]
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#[derive(Debug)]
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struct Item<'a> {
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unsafety: ast::Unsafe,
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abi: Cow<'static, str>,
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vis: Option<&'a ast::Visibility>,
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body: Vec<BodyElement<'a>>,
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span: Span,
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}
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impl<'a> Item<'a> {
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fn from_foreign_mod(fm: &'a ast::ForeignMod, span: Span, config: &Config) -> Item<'a> {
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Item {
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unsafety: fm.unsafety,
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abi: format_extern(
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ast::Extern::from_abi(fm.abi, DUMMY_SP),
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config.force_explicit_abi(),
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),
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vis: None,
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body: fm
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.items
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.iter()
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.map(|i| BodyElement::ForeignItem(i))
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.collect(),
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span,
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}
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}
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}
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#[derive(Debug)]
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enum BodyElement<'a> {
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// Stmt(&'a ast::Stmt),
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// Field(&'a ast::ExprField),
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// Variant(&'a ast::Variant),
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// Item(&'a ast::Item),
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ForeignItem(&'a ast::ForeignItem),
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}
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/// Represents a fn's signature.
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pub(crate) struct FnSig<'a> {
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decl: &'a ast::FnDecl,
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generics: &'a ast::Generics,
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ext: ast::Extern,
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coroutine_kind: Cow<'a, Option<ast::CoroutineKind>>,
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constness: ast::Const,
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defaultness: ast::Defaultness,
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unsafety: ast::Unsafe,
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visibility: &'a ast::Visibility,
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}
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impl<'a> FnSig<'a> {
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pub(crate) fn from_method_sig(
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method_sig: &'a ast::FnSig,
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generics: &'a ast::Generics,
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visibility: &'a ast::Visibility,
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) -> FnSig<'a> {
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FnSig {
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unsafety: method_sig.header.unsafety,
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coroutine_kind: Cow::Borrowed(&method_sig.header.coroutine_kind),
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constness: method_sig.header.constness,
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defaultness: ast::Defaultness::Final,
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ext: method_sig.header.ext,
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decl: &*method_sig.decl,
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generics,
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visibility,
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}
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}
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pub(crate) fn from_fn_kind(
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fn_kind: &'a visit::FnKind<'_>,
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decl: &'a ast::FnDecl,
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defaultness: ast::Defaultness,
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) -> FnSig<'a> {
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match *fn_kind {
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visit::FnKind::Fn(visit::FnCtxt::Assoc(..), _, fn_sig, vis, generics, _) => {
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let mut fn_sig = FnSig::from_method_sig(fn_sig, generics, vis);
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fn_sig.defaultness = defaultness;
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fn_sig
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}
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visit::FnKind::Fn(_, _, fn_sig, vis, generics, _) => FnSig {
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decl,
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generics,
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ext: fn_sig.header.ext,
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constness: fn_sig.header.constness,
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coroutine_kind: Cow::Borrowed(&fn_sig.header.coroutine_kind),
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defaultness,
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unsafety: fn_sig.header.unsafety,
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visibility: vis,
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},
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_ => unreachable!(),
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}
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}
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fn to_str(&self, context: &RewriteContext<'_>) -> String {
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let mut result = String::with_capacity(128);
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// Vis defaultness constness unsafety abi.
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result.push_str(&*format_visibility(context, self.visibility));
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result.push_str(format_defaultness(self.defaultness));
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result.push_str(format_constness(self.constness));
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self.coroutine_kind
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.map(|coroutine_kind| result.push_str(format_coro(&coroutine_kind)));
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result.push_str(format_unsafety(self.unsafety));
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result.push_str(&format_extern(
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self.ext,
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context.config.force_explicit_abi(),
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));
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result
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}
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}
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impl<'a> FmtVisitor<'a> {
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fn format_item(&mut self, item: &Item<'_>) {
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self.buffer.push_str(format_unsafety(item.unsafety));
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self.buffer.push_str(&item.abi);
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let snippet = self.snippet(item.span);
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let brace_pos = snippet.find_uncommented("{").unwrap();
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self.push_str("{");
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if !item.body.is_empty() || contains_comment(&snippet[brace_pos..]) {
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// FIXME: this skips comments between the extern keyword and the opening
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// brace.
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self.last_pos = item.span.lo() + BytePos(brace_pos as u32 + 1);
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self.block_indent = self.block_indent.block_indent(self.config);
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if !item.body.is_empty() {
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for item in &item.body {
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self.format_body_element(item);
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}
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}
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self.format_missing_no_indent(item.span.hi() - BytePos(1));
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self.block_indent = self.block_indent.block_unindent(self.config);
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let indent_str = self.block_indent.to_string(self.config);
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self.push_str(&indent_str);
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}
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self.push_str("}");
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self.last_pos = item.span.hi();
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}
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fn format_body_element(&mut self, element: &BodyElement<'_>) {
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match *element {
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BodyElement::ForeignItem(item) => self.format_foreign_item(item),
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}
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}
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pub(crate) fn format_foreign_mod(&mut self, fm: &ast::ForeignMod, span: Span) {
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let item = Item::from_foreign_mod(fm, span, self.config);
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self.format_item(&item);
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}
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fn format_foreign_item(&mut self, item: &ast::ForeignItem) {
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let rewrite = item.rewrite(&self.get_context(), self.shape());
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let hi = item.span.hi();
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let span = if item.attrs.is_empty() {
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item.span
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} else {
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mk_sp(item.attrs[0].span.lo(), hi)
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};
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self.push_rewrite(span, rewrite);
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self.last_pos = hi;
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}
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pub(crate) fn rewrite_fn_before_block(
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&mut self,
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indent: Indent,
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ident: symbol::Ident,
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fn_sig: &FnSig<'_>,
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span: Span,
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) -> Option<(String, FnBraceStyle)> {
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let context = self.get_context();
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let mut fn_brace_style = newline_for_brace(self.config, &fn_sig.generics.where_clause);
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let (result, _, force_newline_brace) =
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rewrite_fn_base(&context, indent, ident, fn_sig, span, fn_brace_style)?;
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|
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// 2 = ` {`
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if self.config.brace_style() == BraceStyle::AlwaysNextLine
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|| force_newline_brace
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|| last_line_width(&result) + 2 > self.shape().width
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{
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fn_brace_style = FnBraceStyle::NextLine
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}
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|
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Some((result, fn_brace_style))
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}
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pub(crate) fn rewrite_required_fn(
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&mut self,
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indent: Indent,
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ident: symbol::Ident,
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sig: &ast::FnSig,
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|
vis: &ast::Visibility,
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generics: &ast::Generics,
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span: Span,
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) -> Option<String> {
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// Drop semicolon or it will be interpreted as comment.
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let span = mk_sp(span.lo(), span.hi() - BytePos(1));
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let context = self.get_context();
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let (mut result, ends_with_comment, _) = rewrite_fn_base(
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&context,
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indent,
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ident,
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&FnSig::from_method_sig(sig, generics, vis),
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span,
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FnBraceStyle::None,
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)?;
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|
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// If `result` ends with a comment, then remember to add a newline
|
|
if ends_with_comment {
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result.push_str(&indent.to_string_with_newline(context.config));
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}
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|
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// Re-attach semicolon
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result.push(';');
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|
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Some(result)
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}
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|
|
pub(crate) fn single_line_fn(
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&self,
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|
fn_str: &str,
|
|
block: &ast::Block,
|
|
inner_attrs: Option<&[ast::Attribute]>,
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|
) -> Option<String> {
|
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if fn_str.contains('\n') || inner_attrs.map_or(false, |a| !a.is_empty()) {
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return None;
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|
}
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|
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let context = self.get_context();
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|
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if self.config.empty_item_single_line()
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&& is_empty_block(&context, block, None)
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&& self.block_indent.width() + fn_str.len() + 3 <= self.config.max_width()
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&& !last_line_contains_single_line_comment(fn_str)
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{
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return Some(format!("{fn_str} {{}}"));
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}
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|
|
|
if !self.config.fn_single_line() || !is_simple_block_stmt(&context, block, None) {
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return None;
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}
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let res = Stmt::from_ast_node(block.stmts.first()?, true)
|
|
.rewrite(&self.get_context(), self.shape())?;
|
|
|
|
let width = self.block_indent.width() + fn_str.len() + res.len() + 5;
|
|
if !res.contains('\n') && width <= self.config.max_width() {
|
|
Some(format!("{fn_str} {{ {res} }}"))
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
pub(crate) fn visit_static(&mut self, static_parts: &StaticParts<'_>) {
|
|
let rewrite = rewrite_static(&self.get_context(), static_parts, self.block_indent);
|
|
self.push_rewrite(static_parts.span, rewrite);
|
|
}
|
|
|
|
pub(crate) fn visit_struct(&mut self, struct_parts: &StructParts<'_>) {
|
|
let is_tuple = match struct_parts.def {
|
|
ast::VariantData::Tuple(..) => true,
|
|
_ => false,
|
|
};
|
|
let rewrite = format_struct(&self.get_context(), struct_parts, self.block_indent, None)
|
|
.map(|s| if is_tuple { s + ";" } else { s });
|
|
self.push_rewrite(struct_parts.span, rewrite);
|
|
}
|
|
|
|
pub(crate) fn visit_enum(
|
|
&mut self,
|
|
ident: symbol::Ident,
|
|
vis: &ast::Visibility,
|
|
enum_def: &ast::EnumDef,
|
|
generics: &ast::Generics,
|
|
span: Span,
|
|
) {
|
|
let enum_header =
|
|
format_header(&self.get_context(), "enum ", ident, vis, self.block_indent);
|
|
self.push_str(&enum_header);
|
|
|
|
let enum_snippet = self.snippet(span);
|
|
let brace_pos = enum_snippet.find_uncommented("{").unwrap();
|
|
let body_start = span.lo() + BytePos(brace_pos as u32 + 1);
|
|
let generics_str = format_generics(
|
|
&self.get_context(),
|
|
generics,
|
|
self.config.brace_style(),
|
|
if enum_def.variants.is_empty() {
|
|
BracePos::ForceSameLine
|
|
} else {
|
|
BracePos::Auto
|
|
},
|
|
self.block_indent,
|
|
// make a span that starts right after `enum Foo`
|
|
mk_sp(ident.span.hi(), body_start),
|
|
last_line_width(&enum_header),
|
|
)
|
|
.unwrap();
|
|
self.push_str(&generics_str);
|
|
|
|
self.last_pos = body_start;
|
|
|
|
match self.format_variant_list(enum_def, body_start, span.hi()) {
|
|
Some(ref s) if enum_def.variants.is_empty() => self.push_str(s),
|
|
rw => {
|
|
self.push_rewrite(mk_sp(body_start, span.hi()), rw);
|
|
self.block_indent = self.block_indent.block_unindent(self.config);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Format the body of an enum definition
|
|
fn format_variant_list(
|
|
&mut self,
|
|
enum_def: &ast::EnumDef,
|
|
body_lo: BytePos,
|
|
body_hi: BytePos,
|
|
) -> Option<String> {
|
|
if enum_def.variants.is_empty() {
|
|
let mut buffer = String::with_capacity(128);
|
|
// 1 = "}"
|
|
let span = mk_sp(body_lo, body_hi - BytePos(1));
|
|
format_empty_struct_or_tuple(
|
|
&self.get_context(),
|
|
span,
|
|
self.block_indent,
|
|
&mut buffer,
|
|
"",
|
|
"}",
|
|
);
|
|
return Some(buffer);
|
|
}
|
|
let mut result = String::with_capacity(1024);
|
|
let original_offset = self.block_indent;
|
|
self.block_indent = self.block_indent.block_indent(self.config);
|
|
|
|
// If enum variants have discriminants, try to vertically align those,
|
|
// provided the discrims are not shifted too much to the right
|
|
let align_threshold: usize = self.config.enum_discrim_align_threshold();
|
|
let discr_ident_lens: Vec<usize> = enum_def
|
|
.variants
|
|
.iter()
|
|
.filter(|var| var.disr_expr.is_some())
|
|
.map(|var| rewrite_ident(&self.get_context(), var.ident).len())
|
|
.collect();
|
|
// cut the list at the point of longest discrim shorter than the threshold
|
|
// All of the discrims under the threshold will get padded, and all above - left as is.
|
|
let pad_discrim_ident_to = *discr_ident_lens
|
|
.iter()
|
|
.filter(|&l| *l <= align_threshold)
|
|
.max()
|
|
.unwrap_or(&0);
|
|
|
|
let itemize_list_with = |one_line_width: usize| {
|
|
itemize_list(
|
|
self.snippet_provider,
|
|
enum_def.variants.iter(),
|
|
"}",
|
|
",",
|
|
|f| {
|
|
if !f.attrs.is_empty() {
|
|
f.attrs[0].span.lo()
|
|
} else {
|
|
f.span.lo()
|
|
}
|
|
},
|
|
|f| f.span.hi(),
|
|
|f| self.format_variant(f, one_line_width, pad_discrim_ident_to),
|
|
body_lo,
|
|
body_hi,
|
|
false,
|
|
)
|
|
.collect()
|
|
};
|
|
let mut items: Vec<_> = itemize_list_with(self.config.struct_variant_width());
|
|
|
|
// If one of the variants use multiple lines, use multi-lined formatting for all variants.
|
|
let has_multiline_variant = items.iter().any(|item| item.inner_as_ref().contains('\n'));
|
|
let has_single_line_variant = items.iter().any(|item| !item.inner_as_ref().contains('\n'));
|
|
if has_multiline_variant && has_single_line_variant {
|
|
items = itemize_list_with(0);
|
|
}
|
|
|
|
let shape = self.shape().sub_width(2)?;
|
|
let fmt = ListFormatting::new(shape, self.config)
|
|
.trailing_separator(self.config.trailing_comma())
|
|
.preserve_newline(true);
|
|
|
|
let list = write_list(&items, &fmt)?;
|
|
result.push_str(&list);
|
|
result.push_str(&original_offset.to_string_with_newline(self.config));
|
|
result.push('}');
|
|
Some(result)
|
|
}
|
|
|
|
// Variant of an enum.
|
|
fn format_variant(
|
|
&self,
|
|
field: &ast::Variant,
|
|
one_line_width: usize,
|
|
pad_discrim_ident_to: usize,
|
|
) -> Option<String> {
|
|
if contains_skip(&field.attrs) {
|
|
let lo = field.attrs[0].span.lo();
|
|
let span = mk_sp(lo, field.span.hi());
|
|
return Some(self.snippet(span).to_owned());
|
|
}
|
|
|
|
let context = self.get_context();
|
|
let shape = self.shape();
|
|
let attrs_str = if context.config.version() == Version::Two {
|
|
field.attrs.rewrite(&context, shape)?
|
|
} else {
|
|
// Version::One formatting that was off by 1. See issue #5801
|
|
field.attrs.rewrite(&context, shape.sub_width(1)?)?
|
|
};
|
|
// sub_width(1) to take the trailing comma into account
|
|
let shape = shape.sub_width(1)?;
|
|
|
|
let lo = field
|
|
.attrs
|
|
.last()
|
|
.map_or(field.span.lo(), |attr| attr.span.hi());
|
|
let span = mk_sp(lo, field.span.lo());
|
|
|
|
let variant_body = match field.data {
|
|
ast::VariantData::Tuple(..) | ast::VariantData::Struct { .. } => format_struct(
|
|
&context,
|
|
&StructParts::from_variant(field, &context),
|
|
self.block_indent,
|
|
Some(one_line_width),
|
|
)?,
|
|
ast::VariantData::Unit(..) => rewrite_ident(&context, field.ident).to_owned(),
|
|
};
|
|
|
|
let variant_body = if let Some(ref expr) = field.disr_expr {
|
|
let lhs = format!("{variant_body:pad_discrim_ident_to$} =");
|
|
let ex = &*expr.value;
|
|
rewrite_assign_rhs_with(
|
|
&context,
|
|
lhs,
|
|
ex,
|
|
shape,
|
|
&RhsAssignKind::Expr(&ex.kind, ex.span),
|
|
RhsTactics::AllowOverflow,
|
|
)?
|
|
} else {
|
|
variant_body
|
|
};
|
|
|
|
combine_strs_with_missing_comments(&context, &attrs_str, &variant_body, span, shape, false)
|
|
}
|
|
|
|
fn visit_impl_items(&mut self, items: &[ptr::P<ast::AssocItem>]) {
|
|
if self.get_context().config.reorder_impl_items() {
|
|
type TyOpt = Option<ptr::P<ast::Ty>>;
|
|
use crate::ast::AssocItemKind::*;
|
|
let is_type = |ty: &TyOpt| opaque_ty(ty).is_none();
|
|
let is_opaque = |ty: &TyOpt| opaque_ty(ty).is_some();
|
|
let both_type = |l: &TyOpt, r: &TyOpt| is_type(l) && is_type(r);
|
|
let both_opaque = |l: &TyOpt, r: &TyOpt| is_opaque(l) && is_opaque(r);
|
|
let need_empty_line = |a: &ast::AssocItemKind, b: &ast::AssocItemKind| match (a, b) {
|
|
(Type(lty), Type(rty))
|
|
if both_type(<y.ty, &rty.ty) || both_opaque(<y.ty, &rty.ty) =>
|
|
{
|
|
false
|
|
}
|
|
(Const(..), Const(..)) => false,
|
|
_ => true,
|
|
};
|
|
|
|
// Create visitor for each items, then reorder them.
|
|
let mut buffer = vec![];
|
|
for item in items {
|
|
self.visit_impl_item(item);
|
|
buffer.push((self.buffer.clone(), item.clone()));
|
|
self.buffer.clear();
|
|
}
|
|
|
|
buffer.sort_by(|(_, a), (_, b)| match (&a.kind, &b.kind) {
|
|
(Type(lty), Type(rty))
|
|
if both_type(<y.ty, &rty.ty) || both_opaque(<y.ty, &rty.ty) =>
|
|
{
|
|
a.ident.as_str().cmp(b.ident.as_str())
|
|
}
|
|
(Const(..), Const(..)) | (MacCall(..), MacCall(..)) => {
|
|
a.ident.as_str().cmp(b.ident.as_str())
|
|
}
|
|
(Fn(..), Fn(..)) => a.span.lo().cmp(&b.span.lo()),
|
|
(Type(ty), _) if is_type(&ty.ty) => Ordering::Less,
|
|
(_, Type(ty)) if is_type(&ty.ty) => Ordering::Greater,
|
|
(Type(..), _) => Ordering::Less,
|
|
(_, Type(..)) => Ordering::Greater,
|
|
(Const(..), _) => Ordering::Less,
|
|
(_, Const(..)) => Ordering::Greater,
|
|
(MacCall(..), _) => Ordering::Less,
|
|
(_, MacCall(..)) => Ordering::Greater,
|
|
});
|
|
let mut prev_kind = None;
|
|
for (buf, item) in buffer {
|
|
// Make sure that there are at least a single empty line between
|
|
// different impl items.
|
|
if prev_kind
|
|
.as_ref()
|
|
.map_or(false, |prev_kind| need_empty_line(prev_kind, &item.kind))
|
|
{
|
|
self.push_str("\n");
|
|
}
|
|
let indent_str = self.block_indent.to_string_with_newline(self.config);
|
|
self.push_str(&indent_str);
|
|
self.push_str(buf.trim());
|
|
prev_kind = Some(item.kind.clone());
|
|
}
|
|
} else {
|
|
for item in items {
|
|
self.visit_impl_item(item);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(crate) fn format_impl(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
iimpl: &ast::Impl,
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let ast::Impl {
|
|
generics,
|
|
self_ty,
|
|
items,
|
|
..
|
|
} = iimpl;
|
|
let mut result = String::with_capacity(128);
|
|
let ref_and_type = format_impl_ref_and_type(context, item, iimpl, offset)?;
|
|
let sep = offset.to_string_with_newline(context.config);
|
|
result.push_str(&ref_and_type);
|
|
|
|
let where_budget = if result.contains('\n') {
|
|
context.config.max_width()
|
|
} else {
|
|
context.budget(last_line_width(&result))
|
|
};
|
|
|
|
let mut option = WhereClauseOption::snuggled(&ref_and_type);
|
|
let snippet = context.snippet(item.span);
|
|
let open_pos = snippet.find_uncommented("{")? + 1;
|
|
if !contains_comment(&snippet[open_pos..])
|
|
&& items.is_empty()
|
|
&& generics.where_clause.predicates.len() == 1
|
|
&& !result.contains('\n')
|
|
{
|
|
option.suppress_comma();
|
|
option.snuggle();
|
|
option.allow_single_line();
|
|
}
|
|
|
|
let missing_span = mk_sp(self_ty.span.hi(), item.span.hi());
|
|
let where_span_end = context.snippet_provider.opt_span_before(missing_span, "{");
|
|
let where_clause_str = rewrite_where_clause(
|
|
context,
|
|
&generics.where_clause.predicates,
|
|
generics.where_clause.span,
|
|
context.config.brace_style(),
|
|
Shape::legacy(where_budget, offset.block_only()),
|
|
false,
|
|
"{",
|
|
where_span_end,
|
|
self_ty.span.hi(),
|
|
option,
|
|
)?;
|
|
|
|
// If there is no where-clause, we may have missing comments between the trait name and
|
|
// the opening brace.
|
|
if generics.where_clause.predicates.is_empty() {
|
|
if let Some(hi) = where_span_end {
|
|
match recover_missing_comment_in_span(
|
|
mk_sp(self_ty.span.hi(), hi),
|
|
Shape::indented(offset, context.config),
|
|
context,
|
|
last_line_width(&result),
|
|
) {
|
|
Some(ref missing_comment) if !missing_comment.is_empty() => {
|
|
result.push_str(missing_comment);
|
|
}
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
|
|
if is_impl_single_line(context, items.as_slice(), &result, &where_clause_str, item)? {
|
|
result.push_str(&where_clause_str);
|
|
if where_clause_str.contains('\n') {
|
|
// If there is only one where-clause predicate
|
|
// and the where-clause spans multiple lines,
|
|
// then recover the suppressed comma in single line where-clause formatting
|
|
if generics.where_clause.predicates.len() == 1 {
|
|
result.push(',');
|
|
}
|
|
}
|
|
if where_clause_str.contains('\n') || last_line_contains_single_line_comment(&result) {
|
|
result.push_str(&format!("{sep}{{{sep}}}"));
|
|
} else {
|
|
result.push_str(" {}");
|
|
}
|
|
return Some(result);
|
|
}
|
|
|
|
result.push_str(&where_clause_str);
|
|
|
|
let need_newline = last_line_contains_single_line_comment(&result) || result.contains('\n');
|
|
match context.config.brace_style() {
|
|
_ if need_newline => result.push_str(&sep),
|
|
BraceStyle::AlwaysNextLine => result.push_str(&sep),
|
|
BraceStyle::PreferSameLine => result.push(' '),
|
|
BraceStyle::SameLineWhere => {
|
|
if !where_clause_str.is_empty() {
|
|
result.push_str(&sep);
|
|
} else {
|
|
result.push(' ');
|
|
}
|
|
}
|
|
}
|
|
|
|
result.push('{');
|
|
// this is an impl body snippet(impl SampleImpl { /* here */ })
|
|
let lo = max(self_ty.span.hi(), generics.where_clause.span.hi());
|
|
let snippet = context.snippet(mk_sp(lo, item.span.hi()));
|
|
let open_pos = snippet.find_uncommented("{")? + 1;
|
|
|
|
if !items.is_empty() || contains_comment(&snippet[open_pos..]) {
|
|
let mut visitor = FmtVisitor::from_context(context);
|
|
let item_indent = offset.block_only().block_indent(context.config);
|
|
visitor.block_indent = item_indent;
|
|
visitor.last_pos = lo + BytePos(open_pos as u32);
|
|
|
|
visitor.visit_attrs(&item.attrs, ast::AttrStyle::Inner);
|
|
visitor.visit_impl_items(items);
|
|
|
|
visitor.format_missing(item.span.hi() - BytePos(1));
|
|
|
|
let inner_indent_str = visitor.block_indent.to_string_with_newline(context.config);
|
|
let outer_indent_str = offset.block_only().to_string_with_newline(context.config);
|
|
|
|
result.push_str(&inner_indent_str);
|
|
result.push_str(visitor.buffer.trim());
|
|
result.push_str(&outer_indent_str);
|
|
} else if need_newline || !context.config.empty_item_single_line() {
|
|
result.push_str(&sep);
|
|
}
|
|
|
|
result.push('}');
|
|
|
|
Some(result)
|
|
}
|
|
|
|
fn is_impl_single_line(
|
|
context: &RewriteContext<'_>,
|
|
items: &[ptr::P<ast::AssocItem>],
|
|
result: &str,
|
|
where_clause_str: &str,
|
|
item: &ast::Item,
|
|
) -> Option<bool> {
|
|
let snippet = context.snippet(item.span);
|
|
let open_pos = snippet.find_uncommented("{")? + 1;
|
|
|
|
Some(
|
|
context.config.empty_item_single_line()
|
|
&& items.is_empty()
|
|
&& !result.contains('\n')
|
|
&& result.len() + where_clause_str.len() <= context.config.max_width()
|
|
&& !contains_comment(&snippet[open_pos..]),
|
|
)
|
|
}
|
|
|
|
fn format_impl_ref_and_type(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
iimpl: &ast::Impl,
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let ast::Impl {
|
|
unsafety,
|
|
polarity,
|
|
defaultness,
|
|
constness,
|
|
ref generics,
|
|
of_trait: ref trait_ref,
|
|
ref self_ty,
|
|
..
|
|
} = *iimpl;
|
|
let mut result = String::with_capacity(128);
|
|
|
|
result.push_str(&format_visibility(context, &item.vis));
|
|
result.push_str(format_defaultness(defaultness));
|
|
result.push_str(format_unsafety(unsafety));
|
|
|
|
let shape = if context.config.version() == Version::Two {
|
|
Shape::indented(offset + last_line_width(&result), context.config)
|
|
} else {
|
|
generics_shape_from_config(
|
|
context.config,
|
|
Shape::indented(offset + last_line_width(&result), context.config),
|
|
0,
|
|
)?
|
|
};
|
|
let generics_str = rewrite_generics(context, "impl", generics, shape)?;
|
|
result.push_str(&generics_str);
|
|
result.push_str(format_constness_right(constness));
|
|
|
|
let polarity_str = match polarity {
|
|
ast::ImplPolarity::Negative(_) => "!",
|
|
ast::ImplPolarity::Positive => "",
|
|
};
|
|
|
|
let polarity_overhead;
|
|
let trait_ref_overhead;
|
|
if let Some(ref trait_ref) = *trait_ref {
|
|
let result_len = last_line_width(&result);
|
|
result.push_str(&rewrite_trait_ref(
|
|
context,
|
|
trait_ref,
|
|
offset,
|
|
polarity_str,
|
|
result_len,
|
|
)?);
|
|
polarity_overhead = 0; // already written
|
|
trait_ref_overhead = " for".len();
|
|
} else {
|
|
polarity_overhead = polarity_str.len();
|
|
trait_ref_overhead = 0;
|
|
}
|
|
|
|
// Try to put the self type in a single line.
|
|
let curly_brace_overhead = if generics.where_clause.predicates.is_empty() {
|
|
// If there is no where-clause adapt budget for type formatting to take space and curly
|
|
// brace into account.
|
|
match context.config.brace_style() {
|
|
BraceStyle::AlwaysNextLine => 0,
|
|
_ => 2,
|
|
}
|
|
} else {
|
|
0
|
|
};
|
|
let used_space =
|
|
last_line_width(&result) + polarity_overhead + trait_ref_overhead + curly_brace_overhead;
|
|
// 1 = space before the type.
|
|
let budget = context.budget(used_space + 1);
|
|
if let Some(self_ty_str) = self_ty.rewrite(context, Shape::legacy(budget, offset)) {
|
|
if !self_ty_str.contains('\n') {
|
|
if trait_ref.is_some() {
|
|
result.push_str(" for ");
|
|
} else {
|
|
result.push(' ');
|
|
result.push_str(polarity_str);
|
|
}
|
|
result.push_str(&self_ty_str);
|
|
return Some(result);
|
|
}
|
|
}
|
|
|
|
// Couldn't fit the self type on a single line, put it on a new line.
|
|
result.push('\n');
|
|
// Add indentation of one additional tab.
|
|
let new_line_offset = offset.block_indent(context.config);
|
|
result.push_str(&new_line_offset.to_string(context.config));
|
|
if trait_ref.is_some() {
|
|
result.push_str("for ");
|
|
} else {
|
|
result.push_str(polarity_str);
|
|
}
|
|
let budget = context.budget(last_line_width(&result) + polarity_overhead);
|
|
let type_offset = match context.config.indent_style() {
|
|
IndentStyle::Visual => new_line_offset + trait_ref_overhead,
|
|
IndentStyle::Block => new_line_offset,
|
|
};
|
|
result.push_str(&*self_ty.rewrite(context, Shape::legacy(budget, type_offset))?);
|
|
Some(result)
|
|
}
|
|
|
|
fn rewrite_trait_ref(
|
|
context: &RewriteContext<'_>,
|
|
trait_ref: &ast::TraitRef,
|
|
offset: Indent,
|
|
polarity_str: &str,
|
|
result_len: usize,
|
|
) -> Option<String> {
|
|
// 1 = space between generics and trait_ref
|
|
let used_space = 1 + polarity_str.len() + result_len;
|
|
let shape = Shape::indented(offset + used_space, context.config);
|
|
if let Some(trait_ref_str) = trait_ref.rewrite(context, shape) {
|
|
if !trait_ref_str.contains('\n') {
|
|
return Some(format!(" {polarity_str}{trait_ref_str}"));
|
|
}
|
|
}
|
|
// We could not make enough space for trait_ref, so put it on new line.
|
|
let offset = offset.block_indent(context.config);
|
|
let shape = Shape::indented(offset, context.config);
|
|
let trait_ref_str = trait_ref.rewrite(context, shape)?;
|
|
Some(format!(
|
|
"{}{}{}",
|
|
offset.to_string_with_newline(context.config),
|
|
polarity_str,
|
|
trait_ref_str
|
|
))
|
|
}
|
|
|
|
pub(crate) struct StructParts<'a> {
|
|
prefix: &'a str,
|
|
ident: symbol::Ident,
|
|
vis: &'a ast::Visibility,
|
|
def: &'a ast::VariantData,
|
|
generics: Option<&'a ast::Generics>,
|
|
span: Span,
|
|
}
|
|
|
|
impl<'a> StructParts<'a> {
|
|
fn format_header(&self, context: &RewriteContext<'_>, offset: Indent) -> String {
|
|
format_header(context, self.prefix, self.ident, self.vis, offset)
|
|
}
|
|
|
|
fn from_variant(variant: &'a ast::Variant, context: &RewriteContext<'_>) -> Self {
|
|
StructParts {
|
|
prefix: "",
|
|
ident: variant.ident,
|
|
vis: &DEFAULT_VISIBILITY,
|
|
def: &variant.data,
|
|
generics: None,
|
|
span: enum_variant_span(variant, context),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn from_item(item: &'a ast::Item) -> Self {
|
|
let (prefix, def, generics) = match item.kind {
|
|
ast::ItemKind::Struct(ref def, ref generics) => ("struct ", def, generics),
|
|
ast::ItemKind::Union(ref def, ref generics) => ("union ", def, generics),
|
|
_ => unreachable!(),
|
|
};
|
|
StructParts {
|
|
prefix,
|
|
ident: item.ident,
|
|
vis: &item.vis,
|
|
def,
|
|
generics: Some(generics),
|
|
span: item.span,
|
|
}
|
|
}
|
|
}
|
|
|
|
fn enum_variant_span(variant: &ast::Variant, context: &RewriteContext<'_>) -> Span {
|
|
use ast::VariantData::*;
|
|
if let Some(ref anon_const) = variant.disr_expr {
|
|
let span_before_consts = variant.span.until(anon_const.value.span);
|
|
let hi = match &variant.data {
|
|
Struct { .. } => context
|
|
.snippet_provider
|
|
.span_after_last(span_before_consts, "}"),
|
|
Tuple(..) => context
|
|
.snippet_provider
|
|
.span_after_last(span_before_consts, ")"),
|
|
Unit(..) => variant.ident.span.hi(),
|
|
};
|
|
mk_sp(span_before_consts.lo(), hi)
|
|
} else {
|
|
variant.span
|
|
}
|
|
}
|
|
|
|
fn format_struct(
|
|
context: &RewriteContext<'_>,
|
|
struct_parts: &StructParts<'_>,
|
|
offset: Indent,
|
|
one_line_width: Option<usize>,
|
|
) -> Option<String> {
|
|
match struct_parts.def {
|
|
ast::VariantData::Unit(..) => format_unit_struct(context, struct_parts, offset),
|
|
ast::VariantData::Tuple(fields, _) => {
|
|
format_tuple_struct(context, struct_parts, fields, offset)
|
|
}
|
|
ast::VariantData::Struct { fields, .. } => {
|
|
format_struct_struct(context, struct_parts, fields, offset, one_line_width)
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(crate) fn format_trait(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let ast::ItemKind::Trait(trait_kind) = &item.kind else {
|
|
unreachable!();
|
|
};
|
|
let ast::Trait {
|
|
is_auto,
|
|
unsafety,
|
|
ref generics,
|
|
ref bounds,
|
|
ref items,
|
|
} = **trait_kind;
|
|
|
|
let mut result = String::with_capacity(128);
|
|
let header = format!(
|
|
"{}{}{}trait ",
|
|
format_visibility(context, &item.vis),
|
|
format_unsafety(unsafety),
|
|
format_auto(is_auto),
|
|
);
|
|
result.push_str(&header);
|
|
|
|
let body_lo = context.snippet_provider.span_after(item.span, "{");
|
|
|
|
let shape = Shape::indented(offset, context.config).offset_left(result.len())?;
|
|
let generics_str =
|
|
rewrite_generics(context, rewrite_ident(context, item.ident), generics, shape)?;
|
|
result.push_str(&generics_str);
|
|
|
|
// FIXME(#2055): rustfmt fails to format when there are comments between trait bounds.
|
|
if !bounds.is_empty() {
|
|
// Retrieve *unnormalized* ident (See #6069)
|
|
let source_ident = context.snippet(item.ident.span);
|
|
let ident_hi = context.snippet_provider.span_after(item.span, source_ident);
|
|
let bound_hi = bounds.last().unwrap().span().hi();
|
|
let snippet = context.snippet(mk_sp(ident_hi, bound_hi));
|
|
if contains_comment(snippet) {
|
|
return None;
|
|
}
|
|
|
|
result = rewrite_assign_rhs_with(
|
|
context,
|
|
result + ":",
|
|
bounds,
|
|
shape,
|
|
&RhsAssignKind::Bounds,
|
|
RhsTactics::ForceNextLineWithoutIndent,
|
|
)?;
|
|
}
|
|
|
|
// Rewrite where-clause.
|
|
if !generics.where_clause.predicates.is_empty() {
|
|
let where_on_new_line = context.config.indent_style() != IndentStyle::Block;
|
|
|
|
let where_budget = context.budget(last_line_width(&result));
|
|
let pos_before_where = if bounds.is_empty() {
|
|
generics.where_clause.span.lo()
|
|
} else {
|
|
bounds[bounds.len() - 1].span().hi()
|
|
};
|
|
let option = WhereClauseOption::snuggled(&generics_str);
|
|
let where_clause_str = rewrite_where_clause(
|
|
context,
|
|
&generics.where_clause.predicates,
|
|
generics.where_clause.span,
|
|
context.config.brace_style(),
|
|
Shape::legacy(where_budget, offset.block_only()),
|
|
where_on_new_line,
|
|
"{",
|
|
None,
|
|
pos_before_where,
|
|
option,
|
|
)?;
|
|
// If the where-clause cannot fit on the same line,
|
|
// put the where-clause on a new line
|
|
if !where_clause_str.contains('\n')
|
|
&& last_line_width(&result) + where_clause_str.len() + offset.width()
|
|
> context.config.comment_width()
|
|
{
|
|
let width = offset.block_indent + context.config.tab_spaces() - 1;
|
|
let where_indent = Indent::new(0, width);
|
|
result.push_str(&where_indent.to_string_with_newline(context.config));
|
|
}
|
|
result.push_str(&where_clause_str);
|
|
} else {
|
|
let item_snippet = context.snippet(item.span);
|
|
if let Some(lo) = item_snippet.find('/') {
|
|
// 1 = `{`
|
|
let comment_hi = if generics.params.len() > 0 {
|
|
generics.span.lo() - BytePos(1)
|
|
} else {
|
|
body_lo - BytePos(1)
|
|
};
|
|
let comment_lo = item.span.lo() + BytePos(lo as u32);
|
|
if comment_lo < comment_hi {
|
|
match recover_missing_comment_in_span(
|
|
mk_sp(comment_lo, comment_hi),
|
|
Shape::indented(offset, context.config),
|
|
context,
|
|
last_line_width(&result),
|
|
) {
|
|
Some(ref missing_comment) if !missing_comment.is_empty() => {
|
|
result.push_str(missing_comment);
|
|
}
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
let block_span = mk_sp(generics.where_clause.span.hi(), item.span.hi());
|
|
let snippet = context.snippet(block_span);
|
|
let open_pos = snippet.find_uncommented("{")? + 1;
|
|
|
|
match context.config.brace_style() {
|
|
_ if last_line_contains_single_line_comment(&result)
|
|
|| last_line_width(&result) + 2 > context.budget(offset.width()) =>
|
|
{
|
|
result.push_str(&offset.to_string_with_newline(context.config));
|
|
}
|
|
_ if context.config.empty_item_single_line()
|
|
&& items.is_empty()
|
|
&& !result.contains('\n')
|
|
&& !contains_comment(&snippet[open_pos..]) =>
|
|
{
|
|
result.push_str(" {}");
|
|
return Some(result);
|
|
}
|
|
BraceStyle::AlwaysNextLine => {
|
|
result.push_str(&offset.to_string_with_newline(context.config));
|
|
}
|
|
BraceStyle::PreferSameLine => result.push(' '),
|
|
BraceStyle::SameLineWhere => {
|
|
if result.contains('\n')
|
|
|| (!generics.where_clause.predicates.is_empty() && !items.is_empty())
|
|
{
|
|
result.push_str(&offset.to_string_with_newline(context.config));
|
|
} else {
|
|
result.push(' ');
|
|
}
|
|
}
|
|
}
|
|
result.push('{');
|
|
|
|
let outer_indent_str = offset.block_only().to_string_with_newline(context.config);
|
|
|
|
if !items.is_empty() || contains_comment(&snippet[open_pos..]) {
|
|
let mut visitor = FmtVisitor::from_context(context);
|
|
visitor.block_indent = offset.block_only().block_indent(context.config);
|
|
visitor.last_pos = block_span.lo() + BytePos(open_pos as u32);
|
|
|
|
for item in items {
|
|
visitor.visit_trait_item(item);
|
|
}
|
|
|
|
visitor.format_missing(item.span.hi() - BytePos(1));
|
|
|
|
let inner_indent_str = visitor.block_indent.to_string_with_newline(context.config);
|
|
|
|
result.push_str(&inner_indent_str);
|
|
result.push_str(visitor.buffer.trim());
|
|
result.push_str(&outer_indent_str);
|
|
} else if result.contains('\n') {
|
|
result.push_str(&outer_indent_str);
|
|
}
|
|
|
|
result.push('}');
|
|
Some(result)
|
|
}
|
|
|
|
pub(crate) struct TraitAliasBounds<'a> {
|
|
generic_bounds: &'a ast::GenericBounds,
|
|
generics: &'a ast::Generics,
|
|
}
|
|
|
|
impl<'a> Rewrite for TraitAliasBounds<'a> {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
let generic_bounds_str = self.generic_bounds.rewrite(context, shape)?;
|
|
|
|
let mut option = WhereClauseOption::new(true, WhereClauseSpace::None);
|
|
option.allow_single_line();
|
|
|
|
let where_str = rewrite_where_clause(
|
|
context,
|
|
&self.generics.where_clause.predicates,
|
|
self.generics.where_clause.span,
|
|
context.config.brace_style(),
|
|
shape,
|
|
false,
|
|
";",
|
|
None,
|
|
self.generics.where_clause.span.lo(),
|
|
option,
|
|
)?;
|
|
|
|
let fits_single_line = !generic_bounds_str.contains('\n')
|
|
&& !where_str.contains('\n')
|
|
&& generic_bounds_str.len() + where_str.len() < shape.width;
|
|
let space = if generic_bounds_str.is_empty() || where_str.is_empty() {
|
|
Cow::from("")
|
|
} else if fits_single_line {
|
|
Cow::from(" ")
|
|
} else {
|
|
shape.indent.to_string_with_newline(context.config)
|
|
};
|
|
|
|
Some(format!("{generic_bounds_str}{space}{where_str}"))
|
|
}
|
|
}
|
|
|
|
pub(crate) fn format_trait_alias(
|
|
context: &RewriteContext<'_>,
|
|
ident: symbol::Ident,
|
|
vis: &ast::Visibility,
|
|
generics: &ast::Generics,
|
|
generic_bounds: &ast::GenericBounds,
|
|
shape: Shape,
|
|
) -> Option<String> {
|
|
let alias = rewrite_ident(context, ident);
|
|
// 6 = "trait ", 2 = " ="
|
|
let g_shape = shape.offset_left(6)?.sub_width(2)?;
|
|
let generics_str = rewrite_generics(context, alias, generics, g_shape)?;
|
|
let vis_str = format_visibility(context, vis);
|
|
let lhs = format!("{vis_str}trait {generics_str} =");
|
|
// 1 = ";"
|
|
let trait_alias_bounds = TraitAliasBounds {
|
|
generic_bounds,
|
|
generics,
|
|
};
|
|
rewrite_assign_rhs(
|
|
context,
|
|
lhs,
|
|
&trait_alias_bounds,
|
|
&RhsAssignKind::Bounds,
|
|
shape.sub_width(1)?,
|
|
)
|
|
.map(|s| s + ";")
|
|
}
|
|
|
|
fn format_unit_struct(
|
|
context: &RewriteContext<'_>,
|
|
p: &StructParts<'_>,
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let header_str = format_header(context, p.prefix, p.ident, p.vis, offset);
|
|
let generics_str = if let Some(generics) = p.generics {
|
|
let hi = context.snippet_provider.span_before_last(p.span, ";");
|
|
format_generics(
|
|
context,
|
|
generics,
|
|
context.config.brace_style(),
|
|
BracePos::None,
|
|
offset,
|
|
// make a span that starts right after `struct Foo`
|
|
mk_sp(p.ident.span.hi(), hi),
|
|
last_line_width(&header_str),
|
|
)?
|
|
} else {
|
|
String::new()
|
|
};
|
|
Some(format!("{header_str}{generics_str};"))
|
|
}
|
|
|
|
pub(crate) fn format_struct_struct(
|
|
context: &RewriteContext<'_>,
|
|
struct_parts: &StructParts<'_>,
|
|
fields: &[ast::FieldDef],
|
|
offset: Indent,
|
|
one_line_width: Option<usize>,
|
|
) -> Option<String> {
|
|
let mut result = String::with_capacity(1024);
|
|
let span = struct_parts.span;
|
|
|
|
let header_str = struct_parts.format_header(context, offset);
|
|
result.push_str(&header_str);
|
|
|
|
let header_hi = struct_parts.ident.span.hi();
|
|
let body_lo = if let Some(generics) = struct_parts.generics {
|
|
// Adjust the span to start at the end of the generic arguments before searching for the '{'
|
|
let span = span.with_lo(generics.where_clause.span.hi());
|
|
context.snippet_provider.span_after(span, "{")
|
|
} else {
|
|
context.snippet_provider.span_after(span, "{")
|
|
};
|
|
|
|
let generics_str = match struct_parts.generics {
|
|
Some(g) => format_generics(
|
|
context,
|
|
g,
|
|
context.config.brace_style(),
|
|
if fields.is_empty() {
|
|
BracePos::ForceSameLine
|
|
} else {
|
|
BracePos::Auto
|
|
},
|
|
offset,
|
|
// make a span that starts right after `struct Foo`
|
|
mk_sp(header_hi, body_lo),
|
|
last_line_width(&result),
|
|
)?,
|
|
None => {
|
|
// 3 = ` {}`, 2 = ` {`.
|
|
let overhead = if fields.is_empty() { 3 } else { 2 };
|
|
if (context.config.brace_style() == BraceStyle::AlwaysNextLine && !fields.is_empty())
|
|
|| context.config.max_width() < overhead + result.len()
|
|
{
|
|
format!("\n{}{{", offset.block_only().to_string(context.config))
|
|
} else {
|
|
" {".to_owned()
|
|
}
|
|
}
|
|
};
|
|
// 1 = `}`
|
|
let overhead = if fields.is_empty() { 1 } else { 0 };
|
|
let total_width = result.len() + generics_str.len() + overhead;
|
|
if !generics_str.is_empty()
|
|
&& !generics_str.contains('\n')
|
|
&& total_width > context.config.max_width()
|
|
{
|
|
result.push('\n');
|
|
result.push_str(&offset.to_string(context.config));
|
|
result.push_str(generics_str.trim_start());
|
|
} else {
|
|
result.push_str(&generics_str);
|
|
}
|
|
|
|
if fields.is_empty() {
|
|
let inner_span = mk_sp(body_lo, span.hi() - BytePos(1));
|
|
format_empty_struct_or_tuple(context, inner_span, offset, &mut result, "", "}");
|
|
return Some(result);
|
|
}
|
|
|
|
// 3 = ` ` and ` }`
|
|
let one_line_budget = context.budget(result.len() + 3 + offset.width());
|
|
let one_line_budget =
|
|
one_line_width.map_or(0, |one_line_width| min(one_line_width, one_line_budget));
|
|
|
|
let items_str = rewrite_with_alignment(
|
|
fields,
|
|
context,
|
|
Shape::indented(offset.block_indent(context.config), context.config).sub_width(1)?,
|
|
mk_sp(body_lo, span.hi()),
|
|
one_line_budget,
|
|
)?;
|
|
|
|
if !items_str.contains('\n')
|
|
&& !result.contains('\n')
|
|
&& items_str.len() <= one_line_budget
|
|
&& !last_line_contains_single_line_comment(&items_str)
|
|
{
|
|
Some(format!("{result} {items_str} }}"))
|
|
} else {
|
|
Some(format!(
|
|
"{}\n{}{}\n{}}}",
|
|
result,
|
|
offset
|
|
.block_indent(context.config)
|
|
.to_string(context.config),
|
|
items_str,
|
|
offset.to_string(context.config)
|
|
))
|
|
}
|
|
}
|
|
|
|
fn get_bytepos_after_visibility(vis: &ast::Visibility, default_span: Span) -> BytePos {
|
|
match vis.kind {
|
|
ast::VisibilityKind::Restricted { .. } => vis.span.hi(),
|
|
_ => default_span.lo(),
|
|
}
|
|
}
|
|
|
|
// Format tuple or struct without any fields. We need to make sure that the comments
|
|
// inside the delimiters are preserved.
|
|
fn format_empty_struct_or_tuple(
|
|
context: &RewriteContext<'_>,
|
|
span: Span,
|
|
offset: Indent,
|
|
result: &mut String,
|
|
opener: &str,
|
|
closer: &str,
|
|
) {
|
|
// 3 = " {}" or "();"
|
|
let used_width = last_line_used_width(result, offset.width()) + 3;
|
|
if used_width > context.config.max_width() {
|
|
result.push_str(&offset.to_string_with_newline(context.config))
|
|
}
|
|
result.push_str(opener);
|
|
|
|
// indented shape for proper indenting of multi-line comments
|
|
let shape = Shape::indented(offset.block_indent(context.config), context.config);
|
|
match rewrite_missing_comment(span, shape, context) {
|
|
Some(ref s) if s.is_empty() => (),
|
|
Some(ref s) => {
|
|
let is_multi_line = !is_single_line(s);
|
|
if is_multi_line || first_line_contains_single_line_comment(s) {
|
|
let nested_indent_str = offset
|
|
.block_indent(context.config)
|
|
.to_string_with_newline(context.config);
|
|
result.push_str(&nested_indent_str);
|
|
}
|
|
result.push_str(s);
|
|
if is_multi_line || last_line_contains_single_line_comment(s) {
|
|
result.push_str(&offset.to_string_with_newline(context.config));
|
|
}
|
|
}
|
|
None => result.push_str(context.snippet(span)),
|
|
}
|
|
result.push_str(closer);
|
|
}
|
|
|
|
fn format_tuple_struct(
|
|
context: &RewriteContext<'_>,
|
|
struct_parts: &StructParts<'_>,
|
|
fields: &[ast::FieldDef],
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let mut result = String::with_capacity(1024);
|
|
let span = struct_parts.span;
|
|
|
|
let header_str = struct_parts.format_header(context, offset);
|
|
result.push_str(&header_str);
|
|
|
|
let body_lo = if fields.is_empty() {
|
|
let lo = get_bytepos_after_visibility(struct_parts.vis, span);
|
|
context
|
|
.snippet_provider
|
|
.span_after(mk_sp(lo, span.hi()), "(")
|
|
} else {
|
|
fields[0].span.lo()
|
|
};
|
|
let body_hi = if fields.is_empty() {
|
|
context
|
|
.snippet_provider
|
|
.span_after(mk_sp(body_lo, span.hi()), ")")
|
|
} else {
|
|
// This is a dirty hack to work around a missing `)` from the span of the last field.
|
|
let last_arg_span = fields[fields.len() - 1].span;
|
|
context
|
|
.snippet_provider
|
|
.opt_span_after(mk_sp(last_arg_span.hi(), span.hi()), ")")
|
|
.unwrap_or_else(|| last_arg_span.hi())
|
|
};
|
|
|
|
let where_clause_str = match struct_parts.generics {
|
|
Some(generics) => {
|
|
let budget = context.budget(last_line_width(&header_str));
|
|
let shape = Shape::legacy(budget, offset);
|
|
let generics_str = rewrite_generics(context, "", generics, shape)?;
|
|
result.push_str(&generics_str);
|
|
|
|
let where_budget = context.budget(last_line_width(&result));
|
|
let option = WhereClauseOption::new(true, WhereClauseSpace::Newline);
|
|
rewrite_where_clause(
|
|
context,
|
|
&generics.where_clause.predicates,
|
|
generics.where_clause.span,
|
|
context.config.brace_style(),
|
|
Shape::legacy(where_budget, offset.block_only()),
|
|
false,
|
|
";",
|
|
None,
|
|
body_hi,
|
|
option,
|
|
)?
|
|
}
|
|
None => "".to_owned(),
|
|
};
|
|
|
|
if fields.is_empty() {
|
|
let body_hi = context
|
|
.snippet_provider
|
|
.span_before(mk_sp(body_lo, span.hi()), ")");
|
|
let inner_span = mk_sp(body_lo, body_hi);
|
|
format_empty_struct_or_tuple(context, inner_span, offset, &mut result, "(", ")");
|
|
} else {
|
|
let shape = Shape::indented(offset, context.config).sub_width(1)?;
|
|
let lo = if let Some(generics) = struct_parts.generics {
|
|
generics.span.hi()
|
|
} else {
|
|
struct_parts.ident.span.hi()
|
|
};
|
|
result = overflow::rewrite_with_parens(
|
|
context,
|
|
&result,
|
|
fields.iter(),
|
|
shape,
|
|
mk_sp(lo, span.hi()),
|
|
context.config.fn_call_width(),
|
|
None,
|
|
)?;
|
|
}
|
|
|
|
if !where_clause_str.is_empty()
|
|
&& !where_clause_str.contains('\n')
|
|
&& (result.contains('\n')
|
|
|| offset.block_indent + result.len() + where_clause_str.len() + 1
|
|
> context.config.max_width())
|
|
{
|
|
// We need to put the where-clause on a new line, but we didn't
|
|
// know that earlier, so the where-clause will not be indented properly.
|
|
result.push('\n');
|
|
result.push_str(
|
|
&(offset.block_only() + (context.config.tab_spaces() - 1)).to_string(context.config),
|
|
);
|
|
}
|
|
result.push_str(&where_clause_str);
|
|
|
|
Some(result)
|
|
}
|
|
|
|
pub(crate) enum ItemVisitorKind<'a> {
|
|
Item(&'a ast::Item),
|
|
AssocTraitItem(&'a ast::AssocItem),
|
|
AssocImplItem(&'a ast::AssocItem),
|
|
ForeignItem(&'a ast::ForeignItem),
|
|
}
|
|
|
|
struct TyAliasRewriteInfo<'c, 'g>(
|
|
&'c RewriteContext<'c>,
|
|
Indent,
|
|
&'g ast::Generics,
|
|
(ast::TyAliasWhereClause, ast::TyAliasWhereClause),
|
|
usize,
|
|
symbol::Ident,
|
|
Span,
|
|
);
|
|
|
|
pub(crate) fn rewrite_type_alias<'a, 'b>(
|
|
ty_alias_kind: &ast::TyAlias,
|
|
context: &RewriteContext<'a>,
|
|
indent: Indent,
|
|
visitor_kind: &ItemVisitorKind<'b>,
|
|
span: Span,
|
|
) -> Option<String> {
|
|
use ItemVisitorKind::*;
|
|
|
|
let ast::TyAlias {
|
|
defaultness,
|
|
ref generics,
|
|
ref bounds,
|
|
ref ty,
|
|
where_clauses,
|
|
where_predicates_split,
|
|
} = *ty_alias_kind;
|
|
let ty_opt = ty.as_ref();
|
|
let (ident, vis) = match visitor_kind {
|
|
Item(i) => (i.ident, &i.vis),
|
|
AssocTraitItem(i) | AssocImplItem(i) => (i.ident, &i.vis),
|
|
ForeignItem(i) => (i.ident, &i.vis),
|
|
};
|
|
let rw_info = &TyAliasRewriteInfo(
|
|
context,
|
|
indent,
|
|
generics,
|
|
where_clauses,
|
|
where_predicates_split,
|
|
ident,
|
|
span,
|
|
);
|
|
let op_ty = opaque_ty(ty);
|
|
// Type Aliases are formatted slightly differently depending on the context
|
|
// in which they appear, whether they are opaque, and whether they are associated.
|
|
// https://rustc-dev-guide.rust-lang.org/opaque-types-type-alias-impl-trait.html
|
|
// https://github.com/rust-dev-tools/fmt-rfcs/blob/master/guide/items.md#type-aliases
|
|
match (visitor_kind, &op_ty) {
|
|
(Item(_) | AssocTraitItem(_) | ForeignItem(_), Some(op_bounds)) => {
|
|
let op = OpaqueType { bounds: op_bounds };
|
|
rewrite_ty(rw_info, Some(bounds), Some(&op), vis)
|
|
}
|
|
(Item(_) | AssocTraitItem(_) | ForeignItem(_), None) => {
|
|
rewrite_ty(rw_info, Some(bounds), ty_opt, vis)
|
|
}
|
|
(AssocImplItem(_), _) => {
|
|
let result = if let Some(op_bounds) = op_ty {
|
|
let op = OpaqueType { bounds: op_bounds };
|
|
rewrite_ty(rw_info, Some(bounds), Some(&op), &DEFAULT_VISIBILITY)
|
|
} else {
|
|
rewrite_ty(rw_info, Some(bounds), ty_opt, vis)
|
|
}?;
|
|
match defaultness {
|
|
ast::Defaultness::Default(..) => Some(format!("default {result}")),
|
|
_ => Some(result),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn rewrite_ty<R: Rewrite>(
|
|
rw_info: &TyAliasRewriteInfo<'_, '_>,
|
|
generic_bounds_opt: Option<&ast::GenericBounds>,
|
|
rhs: Option<&R>,
|
|
vis: &ast::Visibility,
|
|
) -> Option<String> {
|
|
let mut result = String::with_capacity(128);
|
|
let TyAliasRewriteInfo(
|
|
context,
|
|
indent,
|
|
generics,
|
|
where_clauses,
|
|
where_predicates_split,
|
|
ident,
|
|
span,
|
|
) = *rw_info;
|
|
let (before_where_predicates, after_where_predicates) = generics
|
|
.where_clause
|
|
.predicates
|
|
.split_at(where_predicates_split);
|
|
if !after_where_predicates.is_empty() {
|
|
return None;
|
|
}
|
|
result.push_str(&format!("{}type ", format_visibility(context, vis)));
|
|
let ident_str = rewrite_ident(context, ident);
|
|
|
|
if generics.params.is_empty() {
|
|
result.push_str(ident_str)
|
|
} else {
|
|
// 2 = `= `
|
|
let g_shape = Shape::indented(indent, context.config)
|
|
.offset_left(result.len())?
|
|
.sub_width(2)?;
|
|
let generics_str = rewrite_generics(context, ident_str, generics, g_shape)?;
|
|
result.push_str(&generics_str);
|
|
}
|
|
|
|
if let Some(bounds) = generic_bounds_opt {
|
|
if !bounds.is_empty() {
|
|
// 2 = `: `
|
|
let shape = Shape::indented(indent, context.config).offset_left(result.len() + 2)?;
|
|
let type_bounds = bounds.rewrite(context, shape).map(|s| format!(": {}", s))?;
|
|
result.push_str(&type_bounds);
|
|
}
|
|
}
|
|
|
|
let where_budget = context.budget(last_line_width(&result));
|
|
let mut option = WhereClauseOption::snuggled(&result);
|
|
if rhs.is_none() {
|
|
option.suppress_comma();
|
|
}
|
|
let where_clause_str = rewrite_where_clause(
|
|
context,
|
|
before_where_predicates,
|
|
where_clauses.0.1,
|
|
context.config.brace_style(),
|
|
Shape::legacy(where_budget, indent),
|
|
false,
|
|
"=",
|
|
None,
|
|
generics.span.hi(),
|
|
option,
|
|
)?;
|
|
result.push_str(&where_clause_str);
|
|
|
|
if let Some(ty) = rhs {
|
|
// If there's a where clause, add a newline before the assignment. Otherwise just add a
|
|
// space.
|
|
let has_where = !before_where_predicates.is_empty();
|
|
if has_where {
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
} else {
|
|
result.push(' ');
|
|
}
|
|
|
|
let comment_span = context
|
|
.snippet_provider
|
|
.opt_span_before(span, "=")
|
|
.map(|op_lo| mk_sp(where_clauses.0.1.hi(), op_lo));
|
|
|
|
let lhs = match comment_span {
|
|
Some(comment_span)
|
|
if contains_comment(context.snippet_provider.span_to_snippet(comment_span)?) =>
|
|
{
|
|
let comment_shape = if has_where {
|
|
Shape::indented(indent, context.config)
|
|
} else {
|
|
Shape::indented(indent, context.config)
|
|
.block_left(context.config.tab_spaces())?
|
|
};
|
|
|
|
combine_strs_with_missing_comments(
|
|
context,
|
|
result.trim_end(),
|
|
"=",
|
|
comment_span,
|
|
comment_shape,
|
|
true,
|
|
)?
|
|
}
|
|
_ => format!("{result}="),
|
|
};
|
|
|
|
// 1 = `;`
|
|
let shape = Shape::indented(indent, context.config).sub_width(1)?;
|
|
rewrite_assign_rhs(context, lhs, &*ty, &RhsAssignKind::Ty, shape).map(|s| s + ";")
|
|
} else {
|
|
Some(format!("{result};"))
|
|
}
|
|
}
|
|
|
|
fn type_annotation_spacing(config: &Config) -> (&str, &str) {
|
|
(
|
|
if config.space_before_colon() { " " } else { "" },
|
|
if config.space_after_colon() { " " } else { "" },
|
|
)
|
|
}
|
|
|
|
pub(crate) fn rewrite_struct_field_prefix(
|
|
context: &RewriteContext<'_>,
|
|
field: &ast::FieldDef,
|
|
) -> Option<String> {
|
|
let vis = format_visibility(context, &field.vis);
|
|
let type_annotation_spacing = type_annotation_spacing(context.config);
|
|
Some(match field.ident {
|
|
Some(name) => format!(
|
|
"{}{}{}:",
|
|
vis,
|
|
rewrite_ident(context, name),
|
|
type_annotation_spacing.0
|
|
),
|
|
None => vis.to_string(),
|
|
})
|
|
}
|
|
|
|
impl Rewrite for ast::FieldDef {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
rewrite_struct_field(context, self, shape, 0)
|
|
}
|
|
}
|
|
|
|
pub(crate) fn rewrite_struct_field(
|
|
context: &RewriteContext<'_>,
|
|
field: &ast::FieldDef,
|
|
shape: Shape,
|
|
lhs_max_width: usize,
|
|
) -> Option<String> {
|
|
if contains_skip(&field.attrs) {
|
|
return Some(context.snippet(field.span()).to_owned());
|
|
}
|
|
|
|
let type_annotation_spacing = type_annotation_spacing(context.config);
|
|
let prefix = rewrite_struct_field_prefix(context, field)?;
|
|
|
|
let attrs_str = field.attrs.rewrite(context, shape)?;
|
|
let attrs_extendable = field.ident.is_none() && is_attributes_extendable(&attrs_str);
|
|
let missing_span = if field.attrs.is_empty() {
|
|
mk_sp(field.span.lo(), field.span.lo())
|
|
} else {
|
|
mk_sp(field.attrs.last().unwrap().span.hi(), field.span.lo())
|
|
};
|
|
let mut spacing = String::from(if field.ident.is_some() {
|
|
type_annotation_spacing.1
|
|
} else {
|
|
""
|
|
});
|
|
// Try to put everything on a single line.
|
|
let attr_prefix = combine_strs_with_missing_comments(
|
|
context,
|
|
&attrs_str,
|
|
&prefix,
|
|
missing_span,
|
|
shape,
|
|
attrs_extendable,
|
|
)?;
|
|
let overhead = trimmed_last_line_width(&attr_prefix);
|
|
let lhs_offset = lhs_max_width.saturating_sub(overhead);
|
|
for _ in 0..lhs_offset {
|
|
spacing.push(' ');
|
|
}
|
|
// In this extreme case we will be missing a space between an attribute and a field.
|
|
if prefix.is_empty() && !attrs_str.is_empty() && attrs_extendable && spacing.is_empty() {
|
|
spacing.push(' ');
|
|
}
|
|
let orig_ty = shape
|
|
.offset_left(overhead + spacing.len())
|
|
.and_then(|ty_shape| field.ty.rewrite(context, ty_shape));
|
|
if let Some(ref ty) = orig_ty {
|
|
if !ty.contains('\n') && !contains_comment(context.snippet(missing_span)) {
|
|
return Some(attr_prefix + &spacing + ty);
|
|
}
|
|
}
|
|
|
|
let is_prefix_empty = prefix.is_empty();
|
|
// We must use multiline. We are going to put attributes and a field on different lines.
|
|
let field_str = rewrite_assign_rhs(context, prefix, &*field.ty, &RhsAssignKind::Ty, shape)?;
|
|
// Remove a leading white-space from `rewrite_assign_rhs()` when rewriting a tuple struct.
|
|
let field_str = if is_prefix_empty {
|
|
field_str.trim_start()
|
|
} else {
|
|
&field_str
|
|
};
|
|
combine_strs_with_missing_comments(context, &attrs_str, field_str, missing_span, shape, false)
|
|
}
|
|
|
|
pub(crate) struct StaticParts<'a> {
|
|
prefix: &'a str,
|
|
vis: &'a ast::Visibility,
|
|
ident: symbol::Ident,
|
|
ty: &'a ast::Ty,
|
|
mutability: ast::Mutability,
|
|
expr_opt: Option<&'a ptr::P<ast::Expr>>,
|
|
defaultness: Option<ast::Defaultness>,
|
|
span: Span,
|
|
}
|
|
|
|
impl<'a> StaticParts<'a> {
|
|
pub(crate) fn from_item(item: &'a ast::Item) -> Self {
|
|
let (defaultness, prefix, ty, mutability, expr) = match &item.kind {
|
|
ast::ItemKind::Static(s) => (None, "static", &s.ty, s.mutability, &s.expr),
|
|
ast::ItemKind::Const(c) => (
|
|
Some(c.defaultness),
|
|
"const",
|
|
&c.ty,
|
|
ast::Mutability::Not,
|
|
&c.expr,
|
|
),
|
|
_ => unreachable!(),
|
|
};
|
|
StaticParts {
|
|
prefix,
|
|
vis: &item.vis,
|
|
ident: item.ident,
|
|
ty,
|
|
mutability,
|
|
expr_opt: expr.as_ref(),
|
|
defaultness,
|
|
span: item.span,
|
|
}
|
|
}
|
|
|
|
pub(crate) fn from_trait_item(ti: &'a ast::AssocItem) -> Self {
|
|
let (defaultness, ty, expr_opt) = match &ti.kind {
|
|
ast::AssocItemKind::Const(c) => (c.defaultness, &c.ty, &c.expr),
|
|
_ => unreachable!(),
|
|
};
|
|
StaticParts {
|
|
prefix: "const",
|
|
vis: &ti.vis,
|
|
ident: ti.ident,
|
|
ty,
|
|
mutability: ast::Mutability::Not,
|
|
expr_opt: expr_opt.as_ref(),
|
|
defaultness: Some(defaultness),
|
|
span: ti.span,
|
|
}
|
|
}
|
|
|
|
pub(crate) fn from_impl_item(ii: &'a ast::AssocItem) -> Self {
|
|
let (defaultness, ty, expr) = match &ii.kind {
|
|
ast::AssocItemKind::Const(c) => (c.defaultness, &c.ty, &c.expr),
|
|
_ => unreachable!(),
|
|
};
|
|
StaticParts {
|
|
prefix: "const",
|
|
vis: &ii.vis,
|
|
ident: ii.ident,
|
|
ty,
|
|
mutability: ast::Mutability::Not,
|
|
expr_opt: expr.as_ref(),
|
|
defaultness: Some(defaultness),
|
|
span: ii.span,
|
|
}
|
|
}
|
|
}
|
|
|
|
fn rewrite_static(
|
|
context: &RewriteContext<'_>,
|
|
static_parts: &StaticParts<'_>,
|
|
offset: Indent,
|
|
) -> Option<String> {
|
|
let colon = colon_spaces(context.config);
|
|
let mut prefix = format!(
|
|
"{}{}{} {}{}{}",
|
|
format_visibility(context, static_parts.vis),
|
|
static_parts.defaultness.map_or("", format_defaultness),
|
|
static_parts.prefix,
|
|
format_mutability(static_parts.mutability),
|
|
rewrite_ident(context, static_parts.ident),
|
|
colon,
|
|
);
|
|
// 2 = " =".len()
|
|
let ty_shape =
|
|
Shape::indented(offset.block_only(), context.config).offset_left(prefix.len() + 2)?;
|
|
let ty_str = match static_parts.ty.rewrite(context, ty_shape) {
|
|
Some(ty_str) => ty_str,
|
|
None => {
|
|
if prefix.ends_with(' ') {
|
|
prefix.pop();
|
|
}
|
|
let nested_indent = offset.block_indent(context.config);
|
|
let nested_shape = Shape::indented(nested_indent, context.config);
|
|
let ty_str = static_parts.ty.rewrite(context, nested_shape)?;
|
|
format!(
|
|
"{}{}",
|
|
nested_indent.to_string_with_newline(context.config),
|
|
ty_str
|
|
)
|
|
}
|
|
};
|
|
|
|
if let Some(expr) = static_parts.expr_opt {
|
|
let comments_lo = context.snippet_provider.span_after(static_parts.span, "=");
|
|
let expr_lo = expr.span.lo();
|
|
let comments_span = mk_sp(comments_lo, expr_lo);
|
|
|
|
let lhs = format!("{prefix}{ty_str} =");
|
|
|
|
// 1 = ;
|
|
let remaining_width = context.budget(offset.block_indent + 1);
|
|
rewrite_assign_rhs_with_comments(
|
|
context,
|
|
&lhs,
|
|
&**expr,
|
|
Shape::legacy(remaining_width, offset.block_only()),
|
|
&RhsAssignKind::Expr(&expr.kind, expr.span),
|
|
RhsTactics::Default,
|
|
comments_span,
|
|
true,
|
|
)
|
|
.and_then(|res| recover_comment_removed(res, static_parts.span, context))
|
|
.map(|s| if s.ends_with(';') { s } else { s + ";" })
|
|
} else {
|
|
Some(format!("{prefix}{ty_str};"))
|
|
}
|
|
}
|
|
|
|
// FIXME(calebcartwright) - This is a hack around a bug in the handling of TyKind::ImplTrait.
|
|
// This should be removed once that bug is resolved, with the type alias formatting using the
|
|
// defined Ty for the RHS directly.
|
|
// https://github.com/rust-lang/rustfmt/issues/4373
|
|
// https://github.com/rust-lang/rustfmt/issues/5027
|
|
struct OpaqueType<'a> {
|
|
bounds: &'a ast::GenericBounds,
|
|
}
|
|
|
|
impl<'a> Rewrite for OpaqueType<'a> {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
let shape = shape.offset_left(5)?; // `impl `
|
|
self.bounds
|
|
.rewrite(context, shape)
|
|
.map(|s| format!("impl {}", s))
|
|
}
|
|
}
|
|
|
|
impl Rewrite for ast::FnRetTy {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
match *self {
|
|
ast::FnRetTy::Default(_) => Some(String::new()),
|
|
ast::FnRetTy::Ty(ref ty) => {
|
|
if context.config.version() == Version::One
|
|
|| context.config.indent_style() == IndentStyle::Visual
|
|
{
|
|
let inner_width = shape.width.checked_sub(3)?;
|
|
return ty
|
|
.rewrite(context, Shape::legacy(inner_width, shape.indent + 3))
|
|
.map(|r| format!("-> {}", r));
|
|
}
|
|
|
|
ty.rewrite(context, shape.offset_left(3)?)
|
|
.map(|s| format!("-> {}", s))
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn is_empty_infer(ty: &ast::Ty, pat_span: Span) -> bool {
|
|
match ty.kind {
|
|
ast::TyKind::Infer => ty.span.hi() == pat_span.hi(),
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Recover any missing comments between the param and the type.
|
|
///
|
|
/// # Returns
|
|
///
|
|
/// A 2-len tuple with the comment before the colon in first position, and the comment after the
|
|
/// colon in second position.
|
|
fn get_missing_param_comments(
|
|
context: &RewriteContext<'_>,
|
|
pat_span: Span,
|
|
ty_span: Span,
|
|
shape: Shape,
|
|
) -> (String, String) {
|
|
let missing_comment_span = mk_sp(pat_span.hi(), ty_span.lo());
|
|
|
|
let span_before_colon = {
|
|
let missing_comment_span_hi = context
|
|
.snippet_provider
|
|
.span_before(missing_comment_span, ":");
|
|
mk_sp(pat_span.hi(), missing_comment_span_hi)
|
|
};
|
|
let span_after_colon = {
|
|
let missing_comment_span_lo = context
|
|
.snippet_provider
|
|
.span_after(missing_comment_span, ":");
|
|
mk_sp(missing_comment_span_lo, ty_span.lo())
|
|
};
|
|
|
|
let comment_before_colon = rewrite_missing_comment(span_before_colon, shape, context)
|
|
.filter(|comment| !comment.is_empty())
|
|
.map_or(String::new(), |comment| format!(" {}", comment));
|
|
let comment_after_colon = rewrite_missing_comment(span_after_colon, shape, context)
|
|
.filter(|comment| !comment.is_empty())
|
|
.map_or(String::new(), |comment| format!("{} ", comment));
|
|
(comment_before_colon, comment_after_colon)
|
|
}
|
|
|
|
impl Rewrite for ast::Param {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
let param_attrs_result = self
|
|
.attrs
|
|
.rewrite(context, Shape::legacy(shape.width, shape.indent))?;
|
|
// N.B. Doc comments aren't typically valid syntax, but could appear
|
|
// in the presence of certain macros - https://github.com/rust-lang/rustfmt/issues/4936
|
|
let (span, has_multiple_attr_lines, has_doc_comments) = if !self.attrs.is_empty() {
|
|
let num_attrs = self.attrs.len();
|
|
(
|
|
mk_sp(self.attrs[num_attrs - 1].span.hi(), self.pat.span.lo()),
|
|
param_attrs_result.contains('\n'),
|
|
self.attrs.iter().any(|a| a.is_doc_comment()),
|
|
)
|
|
} else {
|
|
(mk_sp(self.span.lo(), self.span.lo()), false, false)
|
|
};
|
|
|
|
if let Some(ref explicit_self) = self.to_self() {
|
|
rewrite_explicit_self(
|
|
context,
|
|
explicit_self,
|
|
¶m_attrs_result,
|
|
span,
|
|
shape,
|
|
has_multiple_attr_lines,
|
|
)
|
|
} else if is_named_param(self) {
|
|
let param_name = &self
|
|
.pat
|
|
.rewrite(context, Shape::legacy(shape.width, shape.indent))?;
|
|
let mut result = combine_strs_with_missing_comments(
|
|
context,
|
|
¶m_attrs_result,
|
|
param_name,
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines && !has_doc_comments,
|
|
)?;
|
|
|
|
if !is_empty_infer(&*self.ty, self.pat.span) {
|
|
let (before_comment, after_comment) =
|
|
get_missing_param_comments(context, self.pat.span, self.ty.span, shape);
|
|
result.push_str(&before_comment);
|
|
result.push_str(colon_spaces(context.config));
|
|
result.push_str(&after_comment);
|
|
let overhead = last_line_width(&result);
|
|
let max_width = shape.width.checked_sub(overhead)?;
|
|
if let Some(ty_str) = self
|
|
.ty
|
|
.rewrite(context, Shape::legacy(max_width, shape.indent))
|
|
{
|
|
result.push_str(&ty_str);
|
|
} else {
|
|
let prev_str = if param_attrs_result.is_empty() {
|
|
param_attrs_result
|
|
} else {
|
|
param_attrs_result + &shape.to_string_with_newline(context.config)
|
|
};
|
|
|
|
result = combine_strs_with_missing_comments(
|
|
context,
|
|
&prev_str,
|
|
param_name,
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines,
|
|
)?;
|
|
result.push_str(&before_comment);
|
|
result.push_str(colon_spaces(context.config));
|
|
result.push_str(&after_comment);
|
|
let overhead = last_line_width(&result);
|
|
let max_width = shape.width.checked_sub(overhead)?;
|
|
let ty_str = self
|
|
.ty
|
|
.rewrite(context, Shape::legacy(max_width, shape.indent))?;
|
|
result.push_str(&ty_str);
|
|
}
|
|
}
|
|
|
|
Some(result)
|
|
} else {
|
|
self.ty.rewrite(context, shape)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn rewrite_explicit_self(
|
|
context: &RewriteContext<'_>,
|
|
explicit_self: &ast::ExplicitSelf,
|
|
param_attrs: &str,
|
|
span: Span,
|
|
shape: Shape,
|
|
has_multiple_attr_lines: bool,
|
|
) -> Option<String> {
|
|
match explicit_self.node {
|
|
ast::SelfKind::Region(lt, m) => {
|
|
let mut_str = format_mutability(m);
|
|
match lt {
|
|
Some(ref l) => {
|
|
let lifetime_str = l.rewrite(
|
|
context,
|
|
Shape::legacy(context.config.max_width(), Indent::empty()),
|
|
)?;
|
|
Some(combine_strs_with_missing_comments(
|
|
context,
|
|
param_attrs,
|
|
&format!("&{lifetime_str} {mut_str}self"),
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines,
|
|
)?)
|
|
}
|
|
None => Some(combine_strs_with_missing_comments(
|
|
context,
|
|
param_attrs,
|
|
&format!("&{mut_str}self"),
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines,
|
|
)?),
|
|
}
|
|
}
|
|
ast::SelfKind::Explicit(ref ty, mutability) => {
|
|
let type_str = ty.rewrite(
|
|
context,
|
|
Shape::legacy(context.config.max_width(), Indent::empty()),
|
|
)?;
|
|
|
|
Some(combine_strs_with_missing_comments(
|
|
context,
|
|
param_attrs,
|
|
&format!("{}self: {}", format_mutability(mutability), type_str),
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines,
|
|
)?)
|
|
}
|
|
ast::SelfKind::Value(mutability) => Some(combine_strs_with_missing_comments(
|
|
context,
|
|
param_attrs,
|
|
&format!("{}self", format_mutability(mutability)),
|
|
span,
|
|
shape,
|
|
!has_multiple_attr_lines,
|
|
)?),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn span_lo_for_param(param: &ast::Param) -> BytePos {
|
|
if param.attrs.is_empty() {
|
|
if is_named_param(param) {
|
|
param.pat.span.lo()
|
|
} else {
|
|
param.ty.span.lo()
|
|
}
|
|
} else {
|
|
param.attrs[0].span.lo()
|
|
}
|
|
}
|
|
|
|
pub(crate) fn span_hi_for_param(context: &RewriteContext<'_>, param: &ast::Param) -> BytePos {
|
|
match param.ty.kind {
|
|
ast::TyKind::Infer if context.snippet(param.ty.span) == "_" => param.ty.span.hi(),
|
|
ast::TyKind::Infer if is_named_param(param) => param.pat.span.hi(),
|
|
_ => param.ty.span.hi(),
|
|
}
|
|
}
|
|
|
|
pub(crate) fn is_named_param(param: &ast::Param) -> bool {
|
|
if let ast::PatKind::Ident(_, ident, _) = param.pat.kind {
|
|
ident.name != symbol::kw::Empty
|
|
} else {
|
|
true
|
|
}
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
|
|
pub(crate) enum FnBraceStyle {
|
|
SameLine,
|
|
NextLine,
|
|
None,
|
|
}
|
|
|
|
// Return type is (result, force_new_line_for_brace)
|
|
fn rewrite_fn_base(
|
|
context: &RewriteContext<'_>,
|
|
indent: Indent,
|
|
ident: symbol::Ident,
|
|
fn_sig: &FnSig<'_>,
|
|
span: Span,
|
|
fn_brace_style: FnBraceStyle,
|
|
) -> Option<(String, bool, bool)> {
|
|
let mut force_new_line_for_brace = false;
|
|
|
|
let where_clause = &fn_sig.generics.where_clause;
|
|
|
|
let mut result = String::with_capacity(1024);
|
|
result.push_str(&fn_sig.to_str(context));
|
|
|
|
// fn foo
|
|
result.push_str("fn ");
|
|
|
|
// Generics.
|
|
let overhead = if let FnBraceStyle::SameLine = fn_brace_style {
|
|
// 4 = `() {`
|
|
4
|
|
} else {
|
|
// 2 = `()`
|
|
2
|
|
};
|
|
let used_width = last_line_used_width(&result, indent.width());
|
|
let one_line_budget = context.budget(used_width + overhead);
|
|
let shape = Shape {
|
|
width: one_line_budget,
|
|
indent,
|
|
offset: used_width,
|
|
};
|
|
let fd = fn_sig.decl;
|
|
let generics_str = rewrite_generics(
|
|
context,
|
|
rewrite_ident(context, ident),
|
|
&fn_sig.generics,
|
|
shape,
|
|
)?;
|
|
result.push_str(&generics_str);
|
|
|
|
let snuggle_angle_bracket = generics_str
|
|
.lines()
|
|
.last()
|
|
.map_or(false, |l| l.trim_start().len() == 1);
|
|
|
|
// Note that the width and indent don't really matter, we'll re-layout the
|
|
// return type later anyway.
|
|
let ret_str = fd
|
|
.output
|
|
.rewrite(context, Shape::indented(indent, context.config))?;
|
|
|
|
let multi_line_ret_str = ret_str.contains('\n');
|
|
let ret_str_len = if multi_line_ret_str { 0 } else { ret_str.len() };
|
|
|
|
// Params.
|
|
let (one_line_budget, multi_line_budget, mut param_indent) = compute_budgets_for_params(
|
|
context,
|
|
&result,
|
|
indent,
|
|
ret_str_len,
|
|
fn_brace_style,
|
|
multi_line_ret_str,
|
|
)?;
|
|
|
|
debug!(
|
|
"rewrite_fn_base: one_line_budget: {}, multi_line_budget: {}, param_indent: {:?}",
|
|
one_line_budget, multi_line_budget, param_indent
|
|
);
|
|
|
|
result.push('(');
|
|
// Check if vertical layout was forced.
|
|
if one_line_budget == 0
|
|
&& !snuggle_angle_bracket
|
|
&& context.config.indent_style() == IndentStyle::Visual
|
|
{
|
|
result.push_str(¶m_indent.to_string_with_newline(context.config));
|
|
}
|
|
|
|
let params_end = if fd.inputs.is_empty() {
|
|
context
|
|
.snippet_provider
|
|
.span_after(mk_sp(fn_sig.generics.span.hi(), span.hi()), ")")
|
|
} else {
|
|
let last_span = mk_sp(fd.inputs[fd.inputs.len() - 1].span().hi(), span.hi());
|
|
context.snippet_provider.span_after(last_span, ")")
|
|
};
|
|
let params_span = mk_sp(
|
|
context
|
|
.snippet_provider
|
|
.span_after(mk_sp(fn_sig.generics.span.hi(), span.hi()), "("),
|
|
params_end,
|
|
);
|
|
let param_str = rewrite_params(
|
|
context,
|
|
&fd.inputs,
|
|
one_line_budget,
|
|
multi_line_budget,
|
|
indent,
|
|
param_indent,
|
|
params_span,
|
|
fd.c_variadic(),
|
|
)?;
|
|
|
|
let put_params_in_block = match context.config.indent_style() {
|
|
IndentStyle::Block => param_str.contains('\n') || param_str.len() > one_line_budget,
|
|
_ => false,
|
|
} && !fd.inputs.is_empty();
|
|
|
|
let mut params_last_line_contains_comment = false;
|
|
let mut no_params_and_over_max_width = false;
|
|
|
|
if put_params_in_block {
|
|
param_indent = indent.block_indent(context.config);
|
|
result.push_str(¶m_indent.to_string_with_newline(context.config));
|
|
result.push_str(¶m_str);
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
result.push(')');
|
|
} else {
|
|
result.push_str(¶m_str);
|
|
let used_width = last_line_used_width(&result, indent.width()) + first_line_width(&ret_str);
|
|
// Put the closing brace on the next line if it overflows the max width.
|
|
// 1 = `)`
|
|
let closing_paren_overflow_max_width =
|
|
fd.inputs.is_empty() && used_width + 1 > context.config.max_width();
|
|
// If the last line of params contains comment, we cannot put the closing paren
|
|
// on the same line.
|
|
params_last_line_contains_comment = param_str
|
|
.lines()
|
|
.last()
|
|
.map_or(false, |last_line| last_line.contains("//"));
|
|
|
|
if context.config.version() == Version::Two {
|
|
if closing_paren_overflow_max_width {
|
|
result.push(')');
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
no_params_and_over_max_width = true;
|
|
} else if params_last_line_contains_comment {
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
result.push(')');
|
|
no_params_and_over_max_width = true;
|
|
} else {
|
|
result.push(')');
|
|
}
|
|
} else {
|
|
if closing_paren_overflow_max_width || params_last_line_contains_comment {
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
}
|
|
result.push(')');
|
|
}
|
|
}
|
|
|
|
// Return type.
|
|
if let ast::FnRetTy::Ty(..) = fd.output {
|
|
let ret_should_indent = match context.config.indent_style() {
|
|
// If our params are block layout then we surely must have space.
|
|
IndentStyle::Block if put_params_in_block || fd.inputs.is_empty() => false,
|
|
_ if params_last_line_contains_comment => false,
|
|
_ if result.contains('\n') || multi_line_ret_str => true,
|
|
_ => {
|
|
// If the return type would push over the max width, then put the return type on
|
|
// a new line. With the +1 for the signature length an additional space between
|
|
// the closing parenthesis of the param and the arrow '->' is considered.
|
|
let mut sig_length = result.len() + indent.width() + ret_str_len + 1;
|
|
|
|
// If there is no where-clause, take into account the space after the return type
|
|
// and the brace.
|
|
if where_clause.predicates.is_empty() {
|
|
sig_length += 2;
|
|
}
|
|
|
|
sig_length > context.config.max_width()
|
|
}
|
|
};
|
|
let ret_shape = if ret_should_indent {
|
|
if context.config.version() == Version::One
|
|
|| context.config.indent_style() == IndentStyle::Visual
|
|
{
|
|
let indent = if param_str.is_empty() {
|
|
// Aligning with nonexistent params looks silly.
|
|
force_new_line_for_brace = true;
|
|
indent + 4
|
|
} else {
|
|
// FIXME: we might want to check that using the param indent
|
|
// doesn't blow our budget, and if it does, then fallback to
|
|
// the where-clause indent.
|
|
param_indent
|
|
};
|
|
|
|
result.push_str(&indent.to_string_with_newline(context.config));
|
|
Shape::indented(indent, context.config)
|
|
} else {
|
|
let mut ret_shape = Shape::indented(indent, context.config);
|
|
if param_str.is_empty() {
|
|
// Aligning with nonexistent params looks silly.
|
|
force_new_line_for_brace = true;
|
|
ret_shape = if context.use_block_indent() {
|
|
ret_shape.offset_left(4).unwrap_or(ret_shape)
|
|
} else {
|
|
ret_shape.indent = ret_shape.indent + 4;
|
|
ret_shape
|
|
};
|
|
}
|
|
|
|
result.push_str(&ret_shape.indent.to_string_with_newline(context.config));
|
|
ret_shape
|
|
}
|
|
} else {
|
|
if context.config.version() == Version::Two {
|
|
if !param_str.is_empty() || !no_params_and_over_max_width {
|
|
result.push(' ');
|
|
}
|
|
} else {
|
|
result.push(' ');
|
|
}
|
|
|
|
let ret_shape = Shape::indented(indent, context.config);
|
|
ret_shape
|
|
.offset_left(last_line_width(&result))
|
|
.unwrap_or(ret_shape)
|
|
};
|
|
|
|
if multi_line_ret_str || ret_should_indent {
|
|
// Now that we know the proper indent and width, we need to
|
|
// re-layout the return type.
|
|
let ret_str = fd.output.rewrite(context, ret_shape)?;
|
|
result.push_str(&ret_str);
|
|
} else {
|
|
result.push_str(&ret_str);
|
|
}
|
|
|
|
// Comment between return type and the end of the decl.
|
|
let snippet_lo = fd.output.span().hi();
|
|
if where_clause.predicates.is_empty() {
|
|
let snippet_hi = span.hi();
|
|
let snippet = context.snippet(mk_sp(snippet_lo, snippet_hi));
|
|
// Try to preserve the layout of the original snippet.
|
|
let original_starts_with_newline = snippet
|
|
.find(|c| c != ' ')
|
|
.map_or(false, |i| starts_with_newline(&snippet[i..]));
|
|
let original_ends_with_newline = snippet
|
|
.rfind(|c| c != ' ')
|
|
.map_or(false, |i| snippet[i..].ends_with('\n'));
|
|
let snippet = snippet.trim();
|
|
if !snippet.is_empty() {
|
|
result.push(if original_starts_with_newline {
|
|
'\n'
|
|
} else {
|
|
' '
|
|
});
|
|
result.push_str(snippet);
|
|
if original_ends_with_newline {
|
|
force_new_line_for_brace = true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
let pos_before_where = match fd.output {
|
|
ast::FnRetTy::Default(..) => params_span.hi(),
|
|
ast::FnRetTy::Ty(ref ty) => ty.span.hi(),
|
|
};
|
|
|
|
let is_params_multi_lined = param_str.contains('\n');
|
|
|
|
let space = if put_params_in_block && ret_str.is_empty() {
|
|
WhereClauseSpace::Space
|
|
} else {
|
|
WhereClauseSpace::Newline
|
|
};
|
|
let mut option = WhereClauseOption::new(fn_brace_style == FnBraceStyle::None, space);
|
|
if is_params_multi_lined {
|
|
option.veto_single_line();
|
|
}
|
|
let where_clause_str = rewrite_where_clause(
|
|
context,
|
|
&where_clause.predicates,
|
|
where_clause.span,
|
|
context.config.brace_style(),
|
|
Shape::indented(indent, context.config),
|
|
true,
|
|
"{",
|
|
Some(span.hi()),
|
|
pos_before_where,
|
|
option,
|
|
)?;
|
|
// If there are neither where-clause nor return type, we may be missing comments between
|
|
// params and `{`.
|
|
if where_clause_str.is_empty() {
|
|
if let ast::FnRetTy::Default(ret_span) = fd.output {
|
|
match recover_missing_comment_in_span(
|
|
// from after the closing paren to right before block or semicolon
|
|
mk_sp(ret_span.lo(), span.hi()),
|
|
shape,
|
|
context,
|
|
last_line_width(&result),
|
|
) {
|
|
Some(ref missing_comment) if !missing_comment.is_empty() => {
|
|
result.push_str(missing_comment);
|
|
force_new_line_for_brace = true;
|
|
}
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
|
|
result.push_str(&where_clause_str);
|
|
|
|
let ends_with_comment = last_line_contains_single_line_comment(&result);
|
|
force_new_line_for_brace |= ends_with_comment;
|
|
force_new_line_for_brace |=
|
|
is_params_multi_lined && context.config.where_single_line() && !where_clause_str.is_empty();
|
|
Some((result, ends_with_comment, force_new_line_for_brace))
|
|
}
|
|
|
|
/// Kind of spaces to put before `where`.
|
|
#[derive(Copy, Clone)]
|
|
enum WhereClauseSpace {
|
|
/// A single space.
|
|
Space,
|
|
/// A new line.
|
|
Newline,
|
|
/// Nothing.
|
|
None,
|
|
}
|
|
|
|
#[derive(Copy, Clone)]
|
|
struct WhereClauseOption {
|
|
suppress_comma: bool, // Force no trailing comma
|
|
snuggle: WhereClauseSpace,
|
|
allow_single_line: bool, // Try single line where-clause instead of vertical layout
|
|
veto_single_line: bool, // Disallow a single-line where-clause.
|
|
}
|
|
|
|
impl WhereClauseOption {
|
|
fn new(suppress_comma: bool, snuggle: WhereClauseSpace) -> WhereClauseOption {
|
|
WhereClauseOption {
|
|
suppress_comma,
|
|
snuggle,
|
|
allow_single_line: false,
|
|
veto_single_line: false,
|
|
}
|
|
}
|
|
|
|
fn snuggled(current: &str) -> WhereClauseOption {
|
|
WhereClauseOption {
|
|
suppress_comma: false,
|
|
snuggle: if last_line_width(current) == 1 {
|
|
WhereClauseSpace::Space
|
|
} else {
|
|
WhereClauseSpace::Newline
|
|
},
|
|
allow_single_line: false,
|
|
veto_single_line: false,
|
|
}
|
|
}
|
|
|
|
fn suppress_comma(&mut self) {
|
|
self.suppress_comma = true
|
|
}
|
|
|
|
fn allow_single_line(&mut self) {
|
|
self.allow_single_line = true
|
|
}
|
|
|
|
fn snuggle(&mut self) {
|
|
self.snuggle = WhereClauseSpace::Space
|
|
}
|
|
|
|
fn veto_single_line(&mut self) {
|
|
self.veto_single_line = true;
|
|
}
|
|
}
|
|
|
|
fn rewrite_params(
|
|
context: &RewriteContext<'_>,
|
|
params: &[ast::Param],
|
|
one_line_budget: usize,
|
|
multi_line_budget: usize,
|
|
indent: Indent,
|
|
param_indent: Indent,
|
|
span: Span,
|
|
variadic: bool,
|
|
) -> Option<String> {
|
|
if params.is_empty() {
|
|
let comment = context
|
|
.snippet(mk_sp(
|
|
span.lo(),
|
|
// to remove ')'
|
|
span.hi() - BytePos(1),
|
|
))
|
|
.trim();
|
|
return Some(comment.to_owned());
|
|
}
|
|
let param_items: Vec<_> = itemize_list(
|
|
context.snippet_provider,
|
|
params.iter(),
|
|
")",
|
|
",",
|
|
|param| span_lo_for_param(param),
|
|
|param| param.ty.span.hi(),
|
|
|param| {
|
|
param
|
|
.rewrite(context, Shape::legacy(multi_line_budget, param_indent))
|
|
.or_else(|| Some(context.snippet(param.span()).to_owned()))
|
|
},
|
|
span.lo(),
|
|
span.hi(),
|
|
false,
|
|
)
|
|
.collect();
|
|
|
|
let tactic = definitive_tactic(
|
|
¶m_items,
|
|
context
|
|
.config
|
|
.fn_params_layout()
|
|
.to_list_tactic(param_items.len()),
|
|
Separator::Comma,
|
|
one_line_budget,
|
|
);
|
|
let budget = match tactic {
|
|
DefinitiveListTactic::Horizontal => one_line_budget,
|
|
_ => multi_line_budget,
|
|
};
|
|
let indent = match context.config.indent_style() {
|
|
IndentStyle::Block => indent.block_indent(context.config),
|
|
IndentStyle::Visual => param_indent,
|
|
};
|
|
let trailing_separator = if variadic {
|
|
SeparatorTactic::Never
|
|
} else {
|
|
match context.config.indent_style() {
|
|
IndentStyle::Block => context.config.trailing_comma(),
|
|
IndentStyle::Visual => SeparatorTactic::Never,
|
|
}
|
|
};
|
|
let fmt = ListFormatting::new(Shape::legacy(budget, indent), context.config)
|
|
.tactic(tactic)
|
|
.trailing_separator(trailing_separator)
|
|
.ends_with_newline(tactic.ends_with_newline(context.config.indent_style()))
|
|
.preserve_newline(true);
|
|
write_list(¶m_items, &fmt)
|
|
}
|
|
|
|
fn compute_budgets_for_params(
|
|
context: &RewriteContext<'_>,
|
|
result: &str,
|
|
indent: Indent,
|
|
ret_str_len: usize,
|
|
fn_brace_style: FnBraceStyle,
|
|
force_vertical_layout: bool,
|
|
) -> Option<(usize, usize, Indent)> {
|
|
debug!(
|
|
"compute_budgets_for_params {} {:?}, {}, {:?}",
|
|
result.len(),
|
|
indent,
|
|
ret_str_len,
|
|
fn_brace_style,
|
|
);
|
|
// Try keeping everything on the same line.
|
|
if !result.contains('\n') && !force_vertical_layout {
|
|
// 2 = `()`, 3 = `() `, space is before ret_string.
|
|
let overhead = if ret_str_len == 0 { 2 } else { 3 };
|
|
let mut used_space = indent.width() + result.len() + ret_str_len + overhead;
|
|
match fn_brace_style {
|
|
FnBraceStyle::None => used_space += 1, // 1 = `;`
|
|
FnBraceStyle::SameLine => used_space += 2, // 2 = `{}`
|
|
FnBraceStyle::NextLine => (),
|
|
}
|
|
let one_line_budget = context.budget(used_space);
|
|
|
|
if one_line_budget > 0 {
|
|
// 4 = "() {".len()
|
|
let (indent, multi_line_budget) = match context.config.indent_style() {
|
|
IndentStyle::Block => {
|
|
let indent = indent.block_indent(context.config);
|
|
(indent, context.budget(indent.width() + 1))
|
|
}
|
|
IndentStyle::Visual => {
|
|
let indent = indent + result.len() + 1;
|
|
let multi_line_overhead = match fn_brace_style {
|
|
FnBraceStyle::SameLine => 4,
|
|
_ => 2,
|
|
} + indent.width();
|
|
(indent, context.budget(multi_line_overhead))
|
|
}
|
|
};
|
|
|
|
return Some((one_line_budget, multi_line_budget, indent));
|
|
}
|
|
}
|
|
|
|
// Didn't work. we must force vertical layout and put params on a newline.
|
|
let new_indent = indent.block_indent(context.config);
|
|
let used_space = match context.config.indent_style() {
|
|
// 1 = `,`
|
|
IndentStyle::Block => new_indent.width() + 1,
|
|
// Account for `)` and possibly ` {`.
|
|
IndentStyle::Visual => new_indent.width() + if ret_str_len == 0 { 1 } else { 3 },
|
|
};
|
|
Some((0, context.budget(used_space), new_indent))
|
|
}
|
|
|
|
fn newline_for_brace(config: &Config, where_clause: &ast::WhereClause) -> FnBraceStyle {
|
|
let predicate_count = where_clause.predicates.len();
|
|
|
|
if config.where_single_line() && predicate_count == 1 {
|
|
return FnBraceStyle::SameLine;
|
|
}
|
|
let brace_style = config.brace_style();
|
|
|
|
let use_next_line = brace_style == BraceStyle::AlwaysNextLine
|
|
|| (brace_style == BraceStyle::SameLineWhere && predicate_count > 0);
|
|
if use_next_line {
|
|
FnBraceStyle::NextLine
|
|
} else {
|
|
FnBraceStyle::SameLine
|
|
}
|
|
}
|
|
|
|
fn rewrite_generics(
|
|
context: &RewriteContext<'_>,
|
|
ident: &str,
|
|
generics: &ast::Generics,
|
|
shape: Shape,
|
|
) -> Option<String> {
|
|
// FIXME: convert bounds to where-clauses where they get too big or if
|
|
// there is a where-clause at all.
|
|
|
|
if generics.params.is_empty() {
|
|
return Some(ident.to_owned());
|
|
}
|
|
|
|
let params = generics.params.iter();
|
|
overflow::rewrite_with_angle_brackets(context, ident, params, shape, generics.span)
|
|
}
|
|
|
|
fn generics_shape_from_config(config: &Config, shape: Shape, offset: usize) -> Option<Shape> {
|
|
match config.indent_style() {
|
|
IndentStyle::Visual => shape.visual_indent(1 + offset).sub_width(offset + 2),
|
|
IndentStyle::Block => {
|
|
// 1 = ","
|
|
shape
|
|
.block()
|
|
.block_indent(config.tab_spaces())
|
|
.with_max_width(config)
|
|
.sub_width(1)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn rewrite_where_clause_rfc_style(
|
|
context: &RewriteContext<'_>,
|
|
predicates: &[ast::WherePredicate],
|
|
where_span: Span,
|
|
shape: Shape,
|
|
terminator: &str,
|
|
span_end: Option<BytePos>,
|
|
span_end_before_where: BytePos,
|
|
where_clause_option: WhereClauseOption,
|
|
) -> Option<String> {
|
|
let (where_keyword, allow_single_line) = rewrite_where_keyword(
|
|
context,
|
|
predicates,
|
|
where_span,
|
|
shape,
|
|
span_end_before_where,
|
|
where_clause_option,
|
|
)?;
|
|
|
|
// 1 = `,`
|
|
let clause_shape = shape
|
|
.block()
|
|
.with_max_width(context.config)
|
|
.block_left(context.config.tab_spaces())?
|
|
.sub_width(1)?;
|
|
let force_single_line = context.config.where_single_line()
|
|
&& predicates.len() == 1
|
|
&& !where_clause_option.veto_single_line;
|
|
|
|
let preds_str = rewrite_bounds_on_where_clause(
|
|
context,
|
|
predicates,
|
|
clause_shape,
|
|
terminator,
|
|
span_end,
|
|
where_clause_option,
|
|
force_single_line,
|
|
)?;
|
|
|
|
// 6 = `where `
|
|
let clause_sep =
|
|
if allow_single_line && !preds_str.contains('\n') && 6 + preds_str.len() <= shape.width
|
|
|| force_single_line
|
|
{
|
|
Cow::from(" ")
|
|
} else {
|
|
clause_shape.indent.to_string_with_newline(context.config)
|
|
};
|
|
|
|
Some(format!("{where_keyword}{clause_sep}{preds_str}"))
|
|
}
|
|
|
|
/// Rewrite `where` and comment around it.
|
|
fn rewrite_where_keyword(
|
|
context: &RewriteContext<'_>,
|
|
predicates: &[ast::WherePredicate],
|
|
where_span: Span,
|
|
shape: Shape,
|
|
span_end_before_where: BytePos,
|
|
where_clause_option: WhereClauseOption,
|
|
) -> Option<(String, bool)> {
|
|
let block_shape = shape.block().with_max_width(context.config);
|
|
// 1 = `,`
|
|
let clause_shape = block_shape
|
|
.block_left(context.config.tab_spaces())?
|
|
.sub_width(1)?;
|
|
|
|
let comment_separator = |comment: &str, shape: Shape| {
|
|
if comment.is_empty() {
|
|
Cow::from("")
|
|
} else {
|
|
shape.indent.to_string_with_newline(context.config)
|
|
}
|
|
};
|
|
|
|
let (span_before, span_after) =
|
|
missing_span_before_after_where(span_end_before_where, predicates, where_span);
|
|
let (comment_before, comment_after) =
|
|
rewrite_comments_before_after_where(context, span_before, span_after, shape)?;
|
|
|
|
let starting_newline = match where_clause_option.snuggle {
|
|
WhereClauseSpace::Space if comment_before.is_empty() => Cow::from(" "),
|
|
WhereClauseSpace::None => Cow::from(""),
|
|
_ => block_shape.indent.to_string_with_newline(context.config),
|
|
};
|
|
|
|
let newline_before_where = comment_separator(&comment_before, shape);
|
|
let newline_after_where = comment_separator(&comment_after, clause_shape);
|
|
let result = format!(
|
|
"{starting_newline}{comment_before}{newline_before_where}where\
|
|
{newline_after_where}{comment_after}"
|
|
);
|
|
let allow_single_line = where_clause_option.allow_single_line
|
|
&& comment_before.is_empty()
|
|
&& comment_after.is_empty();
|
|
|
|
Some((result, allow_single_line))
|
|
}
|
|
|
|
/// Rewrite bounds on a where clause.
|
|
fn rewrite_bounds_on_where_clause(
|
|
context: &RewriteContext<'_>,
|
|
predicates: &[ast::WherePredicate],
|
|
shape: Shape,
|
|
terminator: &str,
|
|
span_end: Option<BytePos>,
|
|
where_clause_option: WhereClauseOption,
|
|
force_single_line: bool,
|
|
) -> Option<String> {
|
|
let span_start = predicates[0].span().lo();
|
|
// If we don't have the start of the next span, then use the end of the
|
|
// predicates, but that means we miss comments.
|
|
let len = predicates.len();
|
|
let end_of_preds = predicates[len - 1].span().hi();
|
|
let span_end = span_end.unwrap_or(end_of_preds);
|
|
let items = itemize_list(
|
|
context.snippet_provider,
|
|
predicates.iter(),
|
|
terminator,
|
|
",",
|
|
|pred| pred.span().lo(),
|
|
|pred| pred.span().hi(),
|
|
|pred| pred.rewrite(context, shape),
|
|
span_start,
|
|
span_end,
|
|
false,
|
|
);
|
|
let comma_tactic = if where_clause_option.suppress_comma || force_single_line {
|
|
SeparatorTactic::Never
|
|
} else {
|
|
context.config.trailing_comma()
|
|
};
|
|
|
|
// shape should be vertical only and only if we have `force_single_line` option enabled
|
|
// and the number of items of the where-clause is equal to 1
|
|
let shape_tactic = if force_single_line {
|
|
DefinitiveListTactic::Horizontal
|
|
} else {
|
|
DefinitiveListTactic::Vertical
|
|
};
|
|
|
|
let preserve_newline = context.config.version() == Version::One;
|
|
|
|
let fmt = ListFormatting::new(shape, context.config)
|
|
.tactic(shape_tactic)
|
|
.trailing_separator(comma_tactic)
|
|
.preserve_newline(preserve_newline);
|
|
write_list(&items.collect::<Vec<_>>(), &fmt)
|
|
}
|
|
|
|
fn rewrite_where_clause(
|
|
context: &RewriteContext<'_>,
|
|
predicates: &[ast::WherePredicate],
|
|
where_span: Span,
|
|
brace_style: BraceStyle,
|
|
shape: Shape,
|
|
on_new_line: bool,
|
|
terminator: &str,
|
|
span_end: Option<BytePos>,
|
|
span_end_before_where: BytePos,
|
|
where_clause_option: WhereClauseOption,
|
|
) -> Option<String> {
|
|
if predicates.is_empty() {
|
|
return Some(String::new());
|
|
}
|
|
|
|
if context.config.indent_style() == IndentStyle::Block {
|
|
return rewrite_where_clause_rfc_style(
|
|
context,
|
|
predicates,
|
|
where_span,
|
|
shape,
|
|
terminator,
|
|
span_end,
|
|
span_end_before_where,
|
|
where_clause_option,
|
|
);
|
|
}
|
|
|
|
let extra_indent = Indent::new(context.config.tab_spaces(), 0);
|
|
|
|
let offset = match context.config.indent_style() {
|
|
IndentStyle::Block => shape.indent + extra_indent.block_indent(context.config),
|
|
// 6 = "where ".len()
|
|
IndentStyle::Visual => shape.indent + extra_indent + 6,
|
|
};
|
|
// FIXME: if indent_style != Visual, then the budgets below might
|
|
// be out by a char or two.
|
|
|
|
let budget = context.config.max_width() - offset.width();
|
|
let span_start = predicates[0].span().lo();
|
|
// If we don't have the start of the next span, then use the end of the
|
|
// predicates, but that means we miss comments.
|
|
let len = predicates.len();
|
|
let end_of_preds = predicates[len - 1].span().hi();
|
|
let span_end = span_end.unwrap_or(end_of_preds);
|
|
let items = itemize_list(
|
|
context.snippet_provider,
|
|
predicates.iter(),
|
|
terminator,
|
|
",",
|
|
|pred| pred.span().lo(),
|
|
|pred| pred.span().hi(),
|
|
|pred| pred.rewrite(context, Shape::legacy(budget, offset)),
|
|
span_start,
|
|
span_end,
|
|
false,
|
|
);
|
|
let item_vec = items.collect::<Vec<_>>();
|
|
// FIXME: we don't need to collect here
|
|
let tactic = definitive_tactic(&item_vec, ListTactic::Vertical, Separator::Comma, budget);
|
|
|
|
let mut comma_tactic = context.config.trailing_comma();
|
|
// Kind of a hack because we don't usually have trailing commas in where-clauses.
|
|
if comma_tactic == SeparatorTactic::Vertical || where_clause_option.suppress_comma {
|
|
comma_tactic = SeparatorTactic::Never;
|
|
}
|
|
|
|
let fmt = ListFormatting::new(Shape::legacy(budget, offset), context.config)
|
|
.tactic(tactic)
|
|
.trailing_separator(comma_tactic)
|
|
.ends_with_newline(tactic.ends_with_newline(context.config.indent_style()))
|
|
.preserve_newline(true);
|
|
let preds_str = write_list(&item_vec, &fmt)?;
|
|
|
|
let end_length = if terminator == "{" {
|
|
// If the brace is on the next line we don't need to count it otherwise it needs two
|
|
// characters " {"
|
|
match brace_style {
|
|
BraceStyle::AlwaysNextLine | BraceStyle::SameLineWhere => 0,
|
|
BraceStyle::PreferSameLine => 2,
|
|
}
|
|
} else if terminator == "=" {
|
|
2
|
|
} else {
|
|
terminator.len()
|
|
};
|
|
if on_new_line
|
|
|| preds_str.contains('\n')
|
|
|| shape.indent.width() + " where ".len() + preds_str.len() + end_length > shape.width
|
|
{
|
|
Some(format!(
|
|
"\n{}where {}",
|
|
(shape.indent + extra_indent).to_string(context.config),
|
|
preds_str
|
|
))
|
|
} else {
|
|
Some(format!(" where {preds_str}"))
|
|
}
|
|
}
|
|
|
|
fn missing_span_before_after_where(
|
|
before_item_span_end: BytePos,
|
|
predicates: &[ast::WherePredicate],
|
|
where_span: Span,
|
|
) -> (Span, Span) {
|
|
let missing_span_before = mk_sp(before_item_span_end, where_span.lo());
|
|
// 5 = `where`
|
|
let pos_after_where = where_span.lo() + BytePos(5);
|
|
let missing_span_after = mk_sp(pos_after_where, predicates[0].span().lo());
|
|
(missing_span_before, missing_span_after)
|
|
}
|
|
|
|
fn rewrite_comments_before_after_where(
|
|
context: &RewriteContext<'_>,
|
|
span_before_where: Span,
|
|
span_after_where: Span,
|
|
shape: Shape,
|
|
) -> Option<(String, String)> {
|
|
let before_comment = rewrite_missing_comment(span_before_where, shape, context)?;
|
|
let after_comment = rewrite_missing_comment(
|
|
span_after_where,
|
|
shape.block_indent(context.config.tab_spaces()),
|
|
context,
|
|
)?;
|
|
Some((before_comment, after_comment))
|
|
}
|
|
|
|
fn format_header(
|
|
context: &RewriteContext<'_>,
|
|
item_name: &str,
|
|
ident: symbol::Ident,
|
|
vis: &ast::Visibility,
|
|
offset: Indent,
|
|
) -> String {
|
|
let mut result = String::with_capacity(128);
|
|
let shape = Shape::indented(offset, context.config);
|
|
|
|
result.push_str(format_visibility(context, vis).trim());
|
|
|
|
// Check for a missing comment between the visibility and the item name.
|
|
let after_vis = vis.span.hi();
|
|
if let Some(before_item_name) = context
|
|
.snippet_provider
|
|
.opt_span_before(mk_sp(vis.span.lo(), ident.span.hi()), item_name.trim())
|
|
{
|
|
let missing_span = mk_sp(after_vis, before_item_name);
|
|
if let Some(result_with_comment) = combine_strs_with_missing_comments(
|
|
context,
|
|
&result,
|
|
item_name,
|
|
missing_span,
|
|
shape,
|
|
/* allow_extend */ true,
|
|
) {
|
|
result = result_with_comment;
|
|
}
|
|
}
|
|
|
|
result.push_str(rewrite_ident(context, ident));
|
|
|
|
result
|
|
}
|
|
|
|
#[derive(PartialEq, Eq, Clone, Copy)]
|
|
enum BracePos {
|
|
None,
|
|
Auto,
|
|
ForceSameLine,
|
|
}
|
|
|
|
fn format_generics(
|
|
context: &RewriteContext<'_>,
|
|
generics: &ast::Generics,
|
|
brace_style: BraceStyle,
|
|
brace_pos: BracePos,
|
|
offset: Indent,
|
|
span: Span,
|
|
used_width: usize,
|
|
) -> Option<String> {
|
|
let shape = Shape::legacy(context.budget(used_width + offset.width()), offset);
|
|
let mut result = rewrite_generics(context, "", generics, shape)?;
|
|
|
|
// If the generics are not parameterized then generics.span.hi() == 0,
|
|
// so we use span.lo(), which is the position after `struct Foo`.
|
|
let span_end_before_where = if !generics.params.is_empty() {
|
|
generics.span.hi()
|
|
} else {
|
|
span.lo()
|
|
};
|
|
let (same_line_brace, missed_comments) = if !generics.where_clause.predicates.is_empty() {
|
|
let budget = context.budget(last_line_used_width(&result, offset.width()));
|
|
let mut option = WhereClauseOption::snuggled(&result);
|
|
if brace_pos == BracePos::None {
|
|
option.suppress_comma = true;
|
|
}
|
|
let where_clause_str = rewrite_where_clause(
|
|
context,
|
|
&generics.where_clause.predicates,
|
|
generics.where_clause.span,
|
|
brace_style,
|
|
Shape::legacy(budget, offset.block_only()),
|
|
true,
|
|
"{",
|
|
Some(span.hi()),
|
|
span_end_before_where,
|
|
option,
|
|
)?;
|
|
result.push_str(&where_clause_str);
|
|
(
|
|
brace_pos == BracePos::ForceSameLine || brace_style == BraceStyle::PreferSameLine,
|
|
// missed comments are taken care of in #rewrite_where_clause
|
|
None,
|
|
)
|
|
} else {
|
|
(
|
|
brace_pos == BracePos::ForceSameLine
|
|
|| (result.contains('\n') && brace_style == BraceStyle::PreferSameLine
|
|
|| brace_style != BraceStyle::AlwaysNextLine)
|
|
|| trimmed_last_line_width(&result) == 1,
|
|
rewrite_missing_comment(
|
|
mk_sp(
|
|
span_end_before_where,
|
|
if brace_pos == BracePos::None {
|
|
span.hi()
|
|
} else {
|
|
context.snippet_provider.span_before_last(span, "{")
|
|
},
|
|
),
|
|
shape,
|
|
context,
|
|
),
|
|
)
|
|
};
|
|
// add missing comments
|
|
let missed_line_comments = missed_comments
|
|
.filter(|missed_comments| !missed_comments.is_empty())
|
|
.map_or(false, |missed_comments| {
|
|
let is_block = is_last_comment_block(&missed_comments);
|
|
let sep = if is_block { " " } else { "\n" };
|
|
result.push_str(sep);
|
|
result.push_str(&missed_comments);
|
|
!is_block
|
|
});
|
|
if brace_pos == BracePos::None {
|
|
return Some(result);
|
|
}
|
|
let total_used_width = last_line_used_width(&result, used_width);
|
|
let remaining_budget = context.budget(total_used_width);
|
|
// If the same line brace if forced, it indicates that we are rewriting an item with empty body,
|
|
// and hence we take the closer into account as well for one line budget.
|
|
// We assume that the closer has the same length as the opener.
|
|
let overhead = if brace_pos == BracePos::ForceSameLine {
|
|
// 3 = ` {}`
|
|
3
|
|
} else {
|
|
// 2 = ` {`
|
|
2
|
|
};
|
|
let forbid_same_line_brace = missed_line_comments || overhead > remaining_budget;
|
|
if !forbid_same_line_brace && same_line_brace {
|
|
result.push(' ');
|
|
} else {
|
|
result.push('\n');
|
|
result.push_str(&offset.block_only().to_string(context.config));
|
|
}
|
|
result.push('{');
|
|
|
|
Some(result)
|
|
}
|
|
|
|
impl Rewrite for ast::ForeignItem {
|
|
fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
|
|
let attrs_str = self.attrs.rewrite(context, shape)?;
|
|
// Drop semicolon or it will be interpreted as comment.
|
|
// FIXME: this may be a faulty span from libsyntax.
|
|
let span = mk_sp(self.span.lo(), self.span.hi() - BytePos(1));
|
|
|
|
let item_str = match self.kind {
|
|
ast::ForeignItemKind::Fn(ref fn_kind) => {
|
|
let ast::Fn {
|
|
defaultness,
|
|
ref sig,
|
|
ref generics,
|
|
ref body,
|
|
} = **fn_kind;
|
|
if let Some(ref body) = body {
|
|
let mut visitor = FmtVisitor::from_context(context);
|
|
visitor.block_indent = shape.indent;
|
|
visitor.last_pos = self.span.lo();
|
|
let inner_attrs = inner_attributes(&self.attrs);
|
|
let fn_ctxt = visit::FnCtxt::Foreign;
|
|
visitor.visit_fn(
|
|
visit::FnKind::Fn(
|
|
fn_ctxt,
|
|
self.ident,
|
|
sig,
|
|
&self.vis,
|
|
generics,
|
|
Some(body),
|
|
),
|
|
&sig.decl,
|
|
self.span,
|
|
defaultness,
|
|
Some(&inner_attrs),
|
|
);
|
|
Some(visitor.buffer.to_owned())
|
|
} else {
|
|
rewrite_fn_base(
|
|
context,
|
|
shape.indent,
|
|
self.ident,
|
|
&FnSig::from_method_sig(sig, generics, &self.vis),
|
|
span,
|
|
FnBraceStyle::None,
|
|
)
|
|
.map(|(s, _, _)| format!("{};", s))
|
|
}
|
|
}
|
|
ast::ForeignItemKind::Static(ref ty, mutability, _) => {
|
|
// FIXME(#21): we're dropping potential comments in between the
|
|
// function kw here.
|
|
let vis = format_visibility(context, &self.vis);
|
|
let mut_str = format_mutability(mutability);
|
|
let prefix = format!(
|
|
"{}static {}{}:",
|
|
vis,
|
|
mut_str,
|
|
rewrite_ident(context, self.ident)
|
|
);
|
|
// 1 = ;
|
|
rewrite_assign_rhs(
|
|
context,
|
|
prefix,
|
|
&**ty,
|
|
&RhsAssignKind::Ty,
|
|
shape.sub_width(1)?,
|
|
)
|
|
.map(|s| s + ";")
|
|
}
|
|
ast::ForeignItemKind::TyAlias(ref ty_alias) => {
|
|
let (kind, span) = (&ItemVisitorKind::ForeignItem(self), self.span);
|
|
rewrite_type_alias(ty_alias, context, shape.indent, kind, span)
|
|
}
|
|
ast::ForeignItemKind::MacCall(ref mac) => {
|
|
rewrite_macro(mac, None, context, shape, MacroPosition::Item)
|
|
}
|
|
}?;
|
|
|
|
let missing_span = if self.attrs.is_empty() {
|
|
mk_sp(self.span.lo(), self.span.lo())
|
|
} else {
|
|
mk_sp(self.attrs[self.attrs.len() - 1].span.hi(), self.span.lo())
|
|
};
|
|
combine_strs_with_missing_comments(
|
|
context,
|
|
&attrs_str,
|
|
&item_str,
|
|
missing_span,
|
|
shape,
|
|
false,
|
|
)
|
|
}
|
|
}
|
|
|
|
/// Rewrite the attributes of an item.
|
|
fn rewrite_attrs(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
item_str: &str,
|
|
shape: Shape,
|
|
) -> Option<String> {
|
|
let attrs = filter_inline_attrs(&item.attrs, item.span());
|
|
let attrs_str = attrs.rewrite(context, shape)?;
|
|
|
|
let missed_span = if attrs.is_empty() {
|
|
mk_sp(item.span.lo(), item.span.lo())
|
|
} else {
|
|
mk_sp(attrs[attrs.len() - 1].span.hi(), item.span.lo())
|
|
};
|
|
|
|
let allow_extend = if attrs.len() == 1 {
|
|
let line_len = attrs_str.len() + 1 + item_str.len();
|
|
!attrs.first().unwrap().is_doc_comment()
|
|
&& context.config.inline_attribute_width() >= line_len
|
|
} else {
|
|
false
|
|
};
|
|
|
|
combine_strs_with_missing_comments(
|
|
context,
|
|
&attrs_str,
|
|
item_str,
|
|
missed_span,
|
|
shape,
|
|
allow_extend,
|
|
)
|
|
}
|
|
|
|
/// Rewrite an inline mod.
|
|
/// The given shape is used to format the mod's attributes.
|
|
pub(crate) fn rewrite_mod(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
attrs_shape: Shape,
|
|
) -> Option<String> {
|
|
let mut result = String::with_capacity(32);
|
|
result.push_str(&*format_visibility(context, &item.vis));
|
|
result.push_str("mod ");
|
|
result.push_str(rewrite_ident(context, item.ident));
|
|
result.push(';');
|
|
rewrite_attrs(context, item, &result, attrs_shape)
|
|
}
|
|
|
|
/// Rewrite `extern crate foo;`.
|
|
/// The given shape is used to format the extern crate's attributes.
|
|
pub(crate) fn rewrite_extern_crate(
|
|
context: &RewriteContext<'_>,
|
|
item: &ast::Item,
|
|
attrs_shape: Shape,
|
|
) -> Option<String> {
|
|
assert!(is_extern_crate(item));
|
|
let new_str = context.snippet(item.span);
|
|
let item_str = if contains_comment(new_str) {
|
|
new_str.to_owned()
|
|
} else {
|
|
let no_whitespace = &new_str.split_whitespace().collect::<Vec<&str>>().join(" ");
|
|
String::from(&*Regex::new(r"\s;").unwrap().replace(no_whitespace, ";"))
|
|
};
|
|
rewrite_attrs(context, item, &item_str, attrs_shape)
|
|
}
|
|
|
|
/// Returns `true` for `mod foo;`, false for `mod foo { .. }`.
|
|
pub(crate) fn is_mod_decl(item: &ast::Item) -> bool {
|
|
!matches!(
|
|
item.kind,
|
|
ast::ItemKind::Mod(_, ast::ModKind::Loaded(_, ast::Inline::Yes, _))
|
|
)
|
|
}
|
|
|
|
pub(crate) fn is_use_item(item: &ast::Item) -> bool {
|
|
matches!(item.kind, ast::ItemKind::Use(_))
|
|
}
|
|
|
|
pub(crate) fn is_extern_crate(item: &ast::Item) -> bool {
|
|
matches!(item.kind, ast::ItemKind::ExternCrate(..))
|
|
}
|