873 lines
28 KiB
Rust
873 lines
28 KiB
Rust
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// Format list-like macro invocations. These are invocations whose token trees
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// can be interpreted as expressions and separated by commas.
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// Note that these token trees do not actually have to be interpreted as
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// expressions by the compiler. An example of an invocation we would reformat is
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// foo!( x, y, z ). The token x may represent an identifier in the code, but we
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// interpreted as an expression.
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// Macro uses which are not-list like, such as bar!(key => val), will not be
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// reformatted.
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// List-like invocations with parentheses will be formatted as function calls,
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// and those with brackets will be formatted as array literals.
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use std::collections::HashMap;
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use syntax::ast;
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use syntax::codemap::{BytePos, Span};
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use syntax::parse::new_parser_from_tts;
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use syntax::parse::parser::Parser;
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use syntax::parse::token::{BinOpToken, DelimToken, Token};
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use syntax::print::pprust;
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use syntax::symbol;
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use syntax::tokenstream::{Cursor, ThinTokenStream, TokenStream, TokenTree};
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use syntax::util::ThinVec;
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use codemap::SpanUtils;
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use comment::{contains_comment, remove_trailing_white_spaces, FindUncommented};
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use expr::{rewrite_array, rewrite_call_inner};
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use lists::{itemize_list, write_list, DefinitiveListTactic, ListFormatting, SeparatorPlace, SeparatorTactic};
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use rewrite::{Rewrite, RewriteContext};
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use shape::{Indent, Shape};
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use utils::{format_visibility, mk_sp};
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const FORCED_BRACKET_MACROS: &[&str] = &["vec!"];
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// FIXME: use the enum from libsyntax?
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#[derive(Clone, Copy, PartialEq, Eq, Debug)]
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enum MacroStyle {
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Parens,
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Brackets,
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Braces,
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}
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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pub enum MacroPosition {
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Item,
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Statement,
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Expression,
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Pat,
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}
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impl MacroStyle {
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fn opener(&self) -> &'static str {
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match *self {
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MacroStyle::Parens => "(",
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MacroStyle::Brackets => "[",
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MacroStyle::Braces => "{",
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}
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}
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}
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#[derive(Debug)]
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pub enum MacroArg {
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Expr(ast::Expr),
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Ty(ast::Ty),
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Pat(ast::Pat),
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}
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impl Rewrite for MacroArg {
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fn rewrite(&self, context: &RewriteContext, shape: Shape) -> Option<String> {
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match *self {
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MacroArg::Expr(ref expr) => expr.rewrite(context, shape),
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MacroArg::Ty(ref ty) => ty.rewrite(context, shape),
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MacroArg::Pat(ref pat) => pat.rewrite(context, shape),
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}
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}
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}
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fn parse_macro_arg(parser: &mut Parser) -> Option<MacroArg> {
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macro_rules! parse_macro_arg {
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($macro_arg: ident, $parser: ident) => {
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let mut cloned_parser = (*parser).clone();
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match cloned_parser.$parser() {
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Ok(x) => {
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if parser.sess.span_diagnostic.has_errors() {
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parser.sess.span_diagnostic.reset_err_count();
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} else {
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// Parsing succeeded.
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*parser = cloned_parser;
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return Some(MacroArg::$macro_arg((*x).clone()));
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}
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}
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Err(mut e) => {
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e.cancel();
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parser.sess.span_diagnostic.reset_err_count();
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}
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}
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}
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}
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parse_macro_arg!(Expr, parse_expr);
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parse_macro_arg!(Ty, parse_ty);
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parse_macro_arg!(Pat, parse_pat);
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None
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}
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pub fn rewrite_macro(
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mac: &ast::Mac,
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extra_ident: Option<ast::Ident>,
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context: &RewriteContext,
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shape: Shape,
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position: MacroPosition,
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) -> Option<String> {
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let context = &mut context.clone();
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context.inside_macro = true;
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if context.config.use_try_shorthand() {
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if let Some(expr) = convert_try_mac(mac, context) {
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context.inside_macro = false;
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return expr.rewrite(context, shape);
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}
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}
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let original_style = macro_style(mac, context);
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let macro_name = match extra_ident {
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None => format!("{}!", mac.node.path),
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Some(ident) => {
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if ident == symbol::keywords::Invalid.ident() {
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format!("{}!", mac.node.path)
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} else {
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format!("{}! {}", mac.node.path, ident)
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}
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}
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};
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let style = if FORCED_BRACKET_MACROS.contains(&¯o_name[..]) {
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MacroStyle::Brackets
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} else {
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original_style
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};
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let ts: TokenStream = mac.node.stream();
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if ts.is_empty() && !contains_comment(context.snippet(mac.span)) {
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return match style {
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MacroStyle::Parens if position == MacroPosition::Item => {
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Some(format!("{}();", macro_name))
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}
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MacroStyle::Parens => Some(format!("{}()", macro_name)),
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MacroStyle::Brackets => Some(format!("{}[]", macro_name)),
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MacroStyle::Braces => Some(format!("{}{{}}", macro_name)),
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};
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}
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let mut parser = new_parser_from_tts(context.parse_session, ts.trees().collect());
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let mut arg_vec = Vec::new();
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let mut vec_with_semi = false;
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let mut trailing_comma = false;
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if MacroStyle::Braces != style {
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loop {
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match parse_macro_arg(&mut parser) {
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Some(arg) => arg_vec.push(arg),
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None => return Some(context.snippet(mac.span).to_owned()),
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}
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match parser.token {
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Token::Eof => break,
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Token::Comma => (),
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Token::Semi => {
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// Try to parse `vec![expr; expr]`
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if FORCED_BRACKET_MACROS.contains(&¯o_name[..]) {
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parser.bump();
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if parser.token != Token::Eof {
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match parse_macro_arg(&mut parser) {
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Some(arg) => {
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arg_vec.push(arg);
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parser.bump();
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if parser.token == Token::Eof && arg_vec.len() == 2 {
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vec_with_semi = true;
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break;
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}
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}
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None => return Some(context.snippet(mac.span).to_owned()),
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}
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}
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}
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return Some(context.snippet(mac.span).to_owned());
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}
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_ => return Some(context.snippet(mac.span).to_owned()),
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}
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parser.bump();
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if parser.token == Token::Eof {
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trailing_comma = true;
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break;
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}
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}
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}
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match style {
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MacroStyle::Parens => {
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// Format macro invocation as function call, forcing no trailing
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// comma because not all macros support them.
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rewrite_call_inner(
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context,
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¯o_name,
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&arg_vec.iter().map(|e| &*e).collect::<Vec<_>>()[..],
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mac.span,
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shape,
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context.config.width_heuristics().fn_call_width,
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trailing_comma,
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).map(|rw| match position {
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MacroPosition::Item => format!("{};", rw),
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_ => rw,
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})
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}
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MacroStyle::Brackets => {
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let mac_shape = shape.offset_left(macro_name.len())?;
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// Handle special case: `vec![expr; expr]`
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if vec_with_semi {
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let (lbr, rbr) = if context.config.spaces_within_parens_and_brackets() {
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("[ ", " ]")
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} else {
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("[", "]")
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};
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// 6 = `vec!` + `; `
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let total_overhead = lbr.len() + rbr.len() + 6;
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let nested_shape = mac_shape.block_indent(context.config.tab_spaces());
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let lhs = arg_vec[0].rewrite(context, nested_shape)?;
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let rhs = arg_vec[1].rewrite(context, nested_shape)?;
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if !lhs.contains('\n') && !rhs.contains('\n')
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&& lhs.len() + rhs.len() + total_overhead <= shape.width
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{
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Some(format!("{}{}{}; {}{}", macro_name, lbr, lhs, rhs, rbr))
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} else {
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Some(format!(
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"{}{}\n{}{};\n{}{}\n{}{}",
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macro_name,
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lbr,
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nested_shape.indent.to_string(context.config),
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lhs,
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nested_shape.indent.to_string(context.config),
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rhs,
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shape.indent.to_string(context.config),
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rbr
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))
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}
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} else {
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// If we are rewriting `vec!` macro or other special macros,
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// then we can rewrite this as an usual array literal.
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// Otherwise, we must preserve the original existence of trailing comma.
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if FORCED_BRACKET_MACROS.contains(¯o_name.as_str()) {
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context.inside_macro = false;
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trailing_comma = false;
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}
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// Convert `MacroArg` into `ast::Expr`, as `rewrite_array` only accepts the latter.
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let sp = mk_sp(
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context
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.codemap
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.span_after(mac.span, original_style.opener()),
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mac.span.hi() - BytePos(1),
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);
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let arg_vec = &arg_vec.iter().map(|e| &*e).collect::<Vec<_>>()[..];
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let rewrite = rewrite_array(arg_vec, sp, context, mac_shape, trailing_comma)?;
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Some(format!("{}{}", macro_name, rewrite))
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}
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}
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MacroStyle::Braces => {
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// Skip macro invocations with braces, for now.
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indent_macro_snippet(context, context.snippet(mac.span), shape.indent)
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}
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}
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}
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pub fn rewrite_macro_def(
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context: &RewriteContext,
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shape: Shape,
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indent: Indent,
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def: &ast::MacroDef,
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ident: ast::Ident,
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vis: &ast::Visibility,
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span: Span,
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) -> Option<String> {
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let snippet = Some(remove_trailing_white_spaces(context.snippet(span)));
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let mut parser = MacroParser::new(def.stream().into_trees());
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let parsed_def = match parser.parse() {
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Some(def) => def,
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None => return snippet,
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};
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let mut result = if def.legacy {
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String::from("macro_rules!")
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} else {
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format!("{}macro", format_visibility(vis))
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};
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result += " ";
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result += &ident.name.as_str();
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let multi_branch_style = def.legacy || parsed_def.branches.len() != 1;
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let mac_indent = if multi_branch_style {
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result += " {";
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indent.block_indent(context.config)
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} else {
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indent
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};
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let mac_indent_str = mac_indent.to_string(context.config);
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let branch_items = itemize_list(
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context.codemap,
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parsed_def.branches.iter(),
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"",
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"",
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|branch| branch.args_span.lo(),
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|branch| branch.body.hi(),
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|branch| {
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let mut result = String::new();
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// Only attempt to format function-like macros.
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if branch.args_paren_kind != DelimToken::Paren {
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// FIXME(#1539): implement for non-sugared macros.
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return None;
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}
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let args = format_macro_args(branch.args.clone())?;
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if multi_branch_style {
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result += "\n";
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result += &mac_indent_str;
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result += &args;
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result += " =>";
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} else {
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result += &args;
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}
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// The macro body is the most interesting part. It might end up as various
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// AST nodes, but also has special variables (e.g, `$foo`) which can't be
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// parsed as regular Rust code (and note that these can be escaped using
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// `$$`). We'll try and format like an AST node, but we'll substitute
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// variables for new names with the same length first.
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let old_body = context.snippet(branch.body).trim();
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let (body_str, substs) = match replace_names(old_body) {
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Some(result) => result,
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None => return snippet,
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};
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let mut config = context.config.clone();
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config.set().hide_parse_errors(true);
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result += " {";
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let has_block_body = old_body.starts_with('{');
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let body_indent = if has_block_body {
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mac_indent
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} else {
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// We'll hack the indent below, take this into account when formatting,
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let body_indent = mac_indent.block_indent(&config);
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let new_width = config.max_width() - body_indent.width();
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config.set().max_width(new_width);
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body_indent
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};
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// First try to format as items, then as statements.
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let new_body = match ::format_snippet(&body_str, &config) {
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Some(new_body) => new_body,
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None => match ::format_code_block(&body_str, &config) {
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Some(new_body) => new_body,
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None => return None,
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},
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};
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// Indent the body since it is in a block.
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let indent_str = body_indent.to_string(&config);
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let mut new_body = new_body
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.trim_right()
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.lines()
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.fold(String::new(), |mut s, l| {
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if !l.is_empty() {
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s += &indent_str;
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}
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s + l + "\n"
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});
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// Undo our replacement of macro variables.
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// FIXME: this could be *much* more efficient.
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for (old, new) in &substs {
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if old_body.find(new).is_some() {
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debug!(
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"rewrite_macro_def: bailing matching variable: `{}` in `{}`",
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new, ident
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);
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return None;
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}
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new_body = new_body.replace(new, old);
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}
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if has_block_body {
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result += new_body.trim();
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} else if !new_body.is_empty() {
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result += "\n";
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result += &new_body;
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result += &mac_indent_str;
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}
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result += "}";
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if def.legacy {
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result += ";";
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}
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result += "\n";
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Some(result)
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},
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span.lo(),
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span.hi(),
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false
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).collect::<Vec<_>>();
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let arm_shape = shape
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.block_indent(context.config.tab_spaces())
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.with_max_width(context.config);
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let fmt = ListFormatting {
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tactic: DefinitiveListTactic::Vertical,
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separator: "",
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trailing_separator: SeparatorTactic::Never,
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separator_place: SeparatorPlace::Back,
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shape: arm_shape,
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ends_with_newline: false,
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preserve_newline: true,
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config: context.config,
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};
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result += write_list(&branch_items, &fmt)?.as_str();
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if multi_branch_style {
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result += &indent.to_string(context.config);
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result += "}";
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}
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Some(result)
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}
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// Replaces `$foo` with `zfoo`. We must check for name overlap to ensure we
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// aren't causing problems.
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// This should also work for escaped `$` variables, where we leave earlier `$`s.
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fn replace_names(input: &str) -> Option<(String, HashMap<String, String>)> {
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// Each substitution will require five or six extra bytes.
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let mut result = String::with_capacity(input.len() + 64);
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let mut substs = HashMap::new();
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let mut dollar_count = 0;
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let mut cur_name = String::new();
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for c in input.chars() {
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if c == '$' {
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dollar_count += 1;
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} else if dollar_count == 0 {
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result.push(c);
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} else if !c.is_alphanumeric() && !cur_name.is_empty() {
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// Terminates a name following one or more dollars.
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let mut new_name = String::new();
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let mut old_name = String::new();
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old_name.push('$');
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for _ in 0..(dollar_count - 1) {
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new_name.push('$');
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old_name.push('$');
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}
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new_name.push('z');
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new_name.push_str(&cur_name);
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old_name.push_str(&cur_name);
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result.push_str(&new_name);
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substs.insert(old_name, new_name);
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result.push(c);
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dollar_count = 0;
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cur_name = String::new();
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} else if c == '(' && cur_name.is_empty() {
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// FIXME: Support macro def with repeat.
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return None;
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} else if c.is_alphanumeric() {
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cur_name.push(c);
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}
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}
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// FIXME: duplicate code
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if !cur_name.is_empty() {
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let mut new_name = String::new();
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let mut old_name = String::new();
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old_name.push('$');
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for _ in 0..(dollar_count - 1) {
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new_name.push('$');
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old_name.push('$');
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}
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new_name.push('z');
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new_name.push_str(&cur_name);
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old_name.push_str(&cur_name);
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result.push_str(&new_name);
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substs.insert(old_name, new_name);
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}
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debug!("replace_names `{}` {:?}", result, substs);
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Some((result, substs))
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}
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// This is a bit sketchy. The token rules probably need tweaking, but it works
|
|
// for some common cases. I hope the basic logic is sufficient. Note that the
|
|
// meaning of some tokens is a bit different here from usual Rust, e.g., `*`
|
|
// and `(`/`)` have special meaning.
|
|
//
|
|
// We always try and format on one line.
|
|
fn format_macro_args(toks: ThinTokenStream) -> Option<String> {
|
|
let mut result = String::with_capacity(128);
|
|
let mut insert_space = SpaceState::Never;
|
|
|
|
for tok in (toks.into(): TokenStream).trees() {
|
|
match tok {
|
|
TokenTree::Token(_, t) => {
|
|
if !result.is_empty() && force_space_before(&t) {
|
|
insert_space = SpaceState::Always;
|
|
}
|
|
if force_no_space_before(&t) {
|
|
insert_space = SpaceState::Never;
|
|
}
|
|
match (insert_space, ident_like(&t)) {
|
|
(SpaceState::Always, _)
|
|
| (SpaceState::Punctuation, false)
|
|
| (SpaceState::Ident, true) => {
|
|
result.push(' ');
|
|
}
|
|
_ => {}
|
|
}
|
|
result.push_str(&pprust::token_to_string(&t));
|
|
insert_space = next_space(&t);
|
|
}
|
|
TokenTree::Delimited(_, d) => {
|
|
if let SpaceState::Always = insert_space {
|
|
result.push(' ');
|
|
}
|
|
let formatted = format_macro_args(d.tts)?;
|
|
match d.delim {
|
|
DelimToken::Paren => {
|
|
result.push_str(&format!("({})", formatted));
|
|
insert_space = SpaceState::Always;
|
|
}
|
|
DelimToken::Bracket => {
|
|
result.push_str(&format!("[{}]", formatted));
|
|
insert_space = SpaceState::Always;
|
|
}
|
|
DelimToken::Brace => {
|
|
result.push_str(&format!(" {{ {} }}", formatted));
|
|
insert_space = SpaceState::Always;
|
|
}
|
|
DelimToken::NoDelim => {
|
|
result.push_str(&format!("{}", formatted));
|
|
insert_space = SpaceState::Always;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
Some(result)
|
|
}
|
|
|
|
// We should insert a space if the next token is a:
|
|
#[derive(Copy, Clone)]
|
|
enum SpaceState {
|
|
Never,
|
|
Punctuation,
|
|
Ident, // Or ident/literal-like thing.
|
|
Always,
|
|
}
|
|
|
|
fn force_space_before(tok: &Token) -> bool {
|
|
match *tok {
|
|
Token::Eq
|
|
| Token::Lt
|
|
| Token::Le
|
|
| Token::EqEq
|
|
| Token::Ne
|
|
| Token::Ge
|
|
| Token::Gt
|
|
| Token::AndAnd
|
|
| Token::OrOr
|
|
| Token::Not
|
|
| Token::Tilde
|
|
| Token::BinOpEq(_)
|
|
| Token::At
|
|
| Token::RArrow
|
|
| Token::LArrow
|
|
| Token::FatArrow
|
|
| Token::Pound
|
|
| Token::Dollar => true,
|
|
Token::BinOp(bot) => bot != BinOpToken::Star,
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
fn force_no_space_before(tok: &Token) -> bool {
|
|
match *tok {
|
|
Token::Semi | Token::Comma | Token::Dot => true,
|
|
Token::BinOp(bot) => bot == BinOpToken::Star,
|
|
_ => false,
|
|
}
|
|
}
|
|
fn ident_like(tok: &Token) -> bool {
|
|
match *tok {
|
|
Token::Ident(_) | Token::Literal(..) | Token::Lifetime(_) => true,
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
fn next_space(tok: &Token) -> SpaceState {
|
|
match *tok {
|
|
Token::Not
|
|
| Token::Tilde
|
|
| Token::At
|
|
| Token::Comma
|
|
| Token::Dot
|
|
| Token::DotDot
|
|
| Token::DotDotDot
|
|
| Token::DotDotEq
|
|
| Token::DotEq
|
|
| Token::Question
|
|
| Token::Underscore
|
|
| Token::BinOp(_) => SpaceState::Punctuation,
|
|
|
|
Token::ModSep
|
|
| Token::Pound
|
|
| Token::Dollar
|
|
| Token::OpenDelim(_)
|
|
| Token::CloseDelim(_)
|
|
| Token::Whitespace => SpaceState::Never,
|
|
|
|
Token::Literal(..) | Token::Ident(_) | Token::Lifetime(_) => SpaceState::Ident,
|
|
|
|
_ => SpaceState::Always,
|
|
}
|
|
}
|
|
|
|
/// Tries to convert a macro use into a short hand try expression. Returns None
|
|
/// when the macro is not an instance of try! (or parsing the inner expression
|
|
/// failed).
|
|
pub fn convert_try_mac(mac: &ast::Mac, context: &RewriteContext) -> Option<ast::Expr> {
|
|
if &format!("{}", mac.node.path)[..] == "try" {
|
|
let ts: TokenStream = mac.node.tts.clone().into();
|
|
let mut parser = new_parser_from_tts(context.parse_session, ts.trees().collect());
|
|
|
|
Some(ast::Expr {
|
|
id: ast::NodeId::new(0), // dummy value
|
|
node: ast::ExprKind::Try(parser.parse_expr().ok()?),
|
|
span: mac.span, // incorrect span, but shouldn't matter too much
|
|
attrs: ThinVec::new(),
|
|
})
|
|
} else {
|
|
None
|
|
}
|
|
}
|
|
|
|
fn macro_style(mac: &ast::Mac, context: &RewriteContext) -> MacroStyle {
|
|
let snippet = context.snippet(mac.span);
|
|
let paren_pos = snippet.find_uncommented("(").unwrap_or(usize::max_value());
|
|
let bracket_pos = snippet.find_uncommented("[").unwrap_or(usize::max_value());
|
|
let brace_pos = snippet.find_uncommented("{").unwrap_or(usize::max_value());
|
|
|
|
if paren_pos < bracket_pos && paren_pos < brace_pos {
|
|
MacroStyle::Parens
|
|
} else if bracket_pos < brace_pos {
|
|
MacroStyle::Brackets
|
|
} else {
|
|
MacroStyle::Braces
|
|
}
|
|
}
|
|
|
|
/// Indent each line according to the specified `indent`.
|
|
/// e.g.
|
|
/// ```rust
|
|
/// foo!{
|
|
/// x,
|
|
/// y,
|
|
/// foo(
|
|
/// a,
|
|
/// b,
|
|
/// c,
|
|
/// ),
|
|
/// }
|
|
/// ```
|
|
/// will become
|
|
/// ```rust
|
|
/// foo!{
|
|
/// x,
|
|
/// y,
|
|
/// foo(
|
|
/// a,
|
|
/// b,
|
|
/// c,
|
|
// ),
|
|
/// }
|
|
/// ```
|
|
fn indent_macro_snippet(
|
|
context: &RewriteContext,
|
|
macro_str: &str,
|
|
indent: Indent,
|
|
) -> Option<String> {
|
|
let mut lines = macro_str.lines();
|
|
let first_line = lines.next().map(|s| s.trim_right())?;
|
|
let mut trimmed_lines = Vec::with_capacity(16);
|
|
|
|
let min_prefix_space_width = lines
|
|
.filter_map(|line| {
|
|
let prefix_space_width = if is_empty_line(line) {
|
|
None
|
|
} else {
|
|
Some(get_prefix_space_width(context, line))
|
|
};
|
|
trimmed_lines.push((line.trim(), prefix_space_width));
|
|
prefix_space_width
|
|
})
|
|
.min()?;
|
|
|
|
Some(
|
|
String::from(first_line) + "\n"
|
|
+ &trimmed_lines
|
|
.iter()
|
|
.map(|&(line, prefix_space_width)| match prefix_space_width {
|
|
Some(original_indent_width) => {
|
|
let new_indent_width = indent.width()
|
|
+ original_indent_width
|
|
.checked_sub(min_prefix_space_width)
|
|
.unwrap_or(0);
|
|
let new_indent = Indent::from_width(context.config, new_indent_width);
|
|
format!("{}{}", new_indent.to_string(context.config), line.trim())
|
|
}
|
|
None => String::new(),
|
|
})
|
|
.collect::<Vec<_>>()
|
|
.join("\n"),
|
|
)
|
|
}
|
|
|
|
fn get_prefix_space_width(context: &RewriteContext, s: &str) -> usize {
|
|
let mut width = 0;
|
|
for c in s.chars() {
|
|
match c {
|
|
' ' => width += 1,
|
|
'\t' => width += context.config.tab_spaces(),
|
|
_ => return width,
|
|
}
|
|
}
|
|
width
|
|
}
|
|
|
|
fn is_empty_line(s: &str) -> bool {
|
|
s.is_empty() || s.chars().all(char::is_whitespace)
|
|
}
|
|
|
|
// A very simple parser that just parses a macros 2.0 definition into its branches.
|
|
// Currently we do not attempt to parse any further than that.
|
|
#[derive(new)]
|
|
struct MacroParser {
|
|
toks: Cursor,
|
|
}
|
|
|
|
impl MacroParser {
|
|
// (`(` ... `)` `=>` `{` ... `}`)*
|
|
fn parse(&mut self) -> Option<Macro> {
|
|
let mut branches = vec![];
|
|
while self.toks.look_ahead(1).is_some() {
|
|
branches.push(self.parse_branch()?);
|
|
}
|
|
|
|
Some(Macro { branches })
|
|
}
|
|
|
|
// `(` ... `)` `=>` `{` ... `}`
|
|
fn parse_branch(&mut self) -> Option<MacroBranch> {
|
|
let tok = self.toks.next()?;
|
|
let (args_span, args_paren_kind) = match tok {
|
|
TokenTree::Token(..) => return None,
|
|
TokenTree::Delimited(sp, ref d) => (sp, d.delim),
|
|
};
|
|
let args = tok.joint().into();
|
|
match self.toks.next()? {
|
|
TokenTree::Token(_, Token::FatArrow) => {}
|
|
_ => return None,
|
|
}
|
|
let body = match self.toks.next()? {
|
|
TokenTree::Token(..) => return None,
|
|
TokenTree::Delimited(sp, _) => {
|
|
let data = sp.data();
|
|
Span::new(data.lo + BytePos(1), data.hi - BytePos(1), data.ctxt)
|
|
}
|
|
};
|
|
if let Some(TokenTree::Token(_, Token::Semi)) = self.toks.look_ahead(0) {
|
|
self.toks.next();
|
|
}
|
|
Some(MacroBranch {
|
|
args_paren_kind,
|
|
args_span,
|
|
args,
|
|
body,
|
|
})
|
|
}
|
|
}
|
|
|
|
// A parsed macros 2.0 macro definition.
|
|
struct Macro {
|
|
branches: Vec<MacroBranch>,
|
|
}
|
|
|
|
// FIXME: it would be more efficient to use references to the token streams
|
|
// rather than clone them, if we can make the borrowing work out.
|
|
struct MacroBranch {
|
|
args_paren_kind: DelimToken,
|
|
args_span: Span,
|
|
args: ThinTokenStream,
|
|
body: Span,
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use super::*;
|
|
use syntax::parse::{parse_stream_from_source_str, ParseSess};
|
|
use syntax::codemap::{FileName, FilePathMapping};
|
|
|
|
fn format_macro_args_str(s: &str) -> String {
|
|
let input = parse_stream_from_source_str(
|
|
FileName::Custom("stdin".to_owned()),
|
|
s.to_owned(),
|
|
&ParseSess::new(FilePathMapping::empty()),
|
|
None,
|
|
);
|
|
format_macro_args(input.into()).unwrap()
|
|
}
|
|
|
|
#[test]
|
|
fn test_format_macro_args() {
|
|
assert_eq!(format_macro_args_str(""), "".to_owned());
|
|
assert_eq!(format_macro_args_str("$ x : ident"), "$x: ident".to_owned());
|
|
assert_eq!(
|
|
format_macro_args_str("$ m1 : ident , $ m2 : ident , $ x : ident"),
|
|
"$m1: ident, $m2: ident, $x: ident".to_owned()
|
|
);
|
|
assert_eq!(
|
|
format_macro_args_str("$($beginning:ident),*;$middle:ident;$($end:ident),*"),
|
|
"$($beginning: ident),*; $middle: ident; $($end: ident),*".to_owned()
|
|
);
|
|
assert_eq!(
|
|
format_macro_args_str(
|
|
"$ name : ident ( $ ( $ dol : tt $ var : ident ) * ) $ ( $ body : tt ) *"
|
|
),
|
|
"$name: ident($($dol: tt $var: ident)*) $($body: tt)*".to_owned()
|
|
);
|
|
}
|
|
}
|