rust/crates/ide_assists/src/handlers/extract_function.rs
bors[bot] d56c8796d6
Merge #10532
10532: Rename `descend_into_macros` Function per FIXME comment r=Veykril a=mirkoRainer

This renames `descend_into_macros` to  `descend_into_macros_single` and `descend_into_macros_many` into `descend_into_macros`.
 However, this does not touch a function in `SemanticsImpl` of same name.

I was prompted to do this per a FIXME comment, which is removed in this PR.

Co-authored-by: Mirko Rainer <mirkorainer@outlook.com>
2021-10-12 17:24:50 +00:00

4289 lines
97 KiB
Rust

use std::{hash::BuildHasherDefault, iter};
use ast::make;
use either::Either;
use hir::{HirDisplay, InFile, Local, Semantics, TypeInfo};
use ide_db::{
defs::{Definition, NameRefClass},
helpers::node_ext::{preorder_expr, walk_expr, walk_pat, walk_patterns_in_expr},
search::{FileReference, ReferenceCategory, SearchScope},
RootDatabase,
};
use itertools::Itertools;
use rustc_hash::FxHasher;
use stdx::format_to;
use syntax::{
ast::{
self,
edit::{AstNodeEdit, IndentLevel},
AstNode,
},
match_ast, ted, SyntaxElement,
SyntaxKind::{self, COMMENT},
SyntaxNode, SyntaxToken, TextRange, TextSize, TokenAtOffset, WalkEvent, T,
};
use crate::{
assist_context::{AssistContext, Assists, TreeMutator},
AssistId,
};
type FxIndexSet<T> = indexmap::IndexSet<T, BuildHasherDefault<FxHasher>>;
// Assist: extract_function
//
// Extracts selected statements into new function.
//
// ```
// fn main() {
// let n = 1;
// $0let m = n + 2;
// let k = m + n;$0
// let g = 3;
// }
// ```
// ->
// ```
// fn main() {
// let n = 1;
// fun_name(n);
// let g = 3;
// }
//
// fn $0fun_name(n: i32) {
// let m = n + 2;
// let k = m + n;
// }
// ```
pub(crate) fn extract_function(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
let range = ctx.selection_trimmed();
if range.is_empty() {
return None;
}
let node = ctx.covering_element();
if node.kind() == COMMENT {
cov_mark::hit!(extract_function_in_comment_is_not_applicable);
return None;
}
let node = match node {
syntax::NodeOrToken::Node(n) => n,
syntax::NodeOrToken::Token(t) => t.parent()?,
};
let body = extraction_target(&node, range)?;
let container_info = body.analyze_container(&ctx.sema)?;
let (locals_used, self_param) = body.analyze(&ctx.sema);
let anchor = if self_param.is_some() { Anchor::Method } else { Anchor::Freestanding };
let insert_after = node_to_insert_after(&body, anchor)?;
let module = ctx.sema.scope(&insert_after).module()?;
let ret_ty = body.return_ty(ctx)?;
let control_flow = body.external_control_flow(ctx, &container_info)?;
let ret_values = body.ret_values(ctx, node.parent().as_ref().unwrap_or(&node));
let target_range = body.text_range();
acc.add(
AssistId("extract_function", crate::AssistKind::RefactorExtract),
"Extract into function",
target_range,
move |builder| {
let outliving_locals: Vec<_> = ret_values.collect();
if stdx::never!(!outliving_locals.is_empty() && !ret_ty.is_unit()) {
// We should not have variables that outlive body if we have expression block
return;
}
let params =
body.extracted_function_params(ctx, &container_info, locals_used.iter().copied());
let fun = Function {
name: make::name_ref("fun_name"),
self_param,
params,
control_flow,
ret_ty,
body,
outliving_locals,
mods: container_info,
};
let new_indent = IndentLevel::from_node(&insert_after);
let old_indent = fun.body.indent_level();
builder.replace(target_range, make_call(ctx, &fun, old_indent));
let fn_def = format_function(ctx, module, &fun, old_indent, new_indent);
let insert_offset = insert_after.text_range().end();
match ctx.config.snippet_cap {
Some(cap) => builder.insert_snippet(cap, insert_offset, fn_def),
None => builder.insert(insert_offset, fn_def),
}
},
)
}
/// Try to guess what user wants to extract
///
/// We have basically have two cases:
/// * We want whole node, like `loop {}`, `2 + 2`, `{ let n = 1; }` exprs.
/// Then we can use `ast::Expr`
/// * We want a few statements for a block. E.g.
/// ```rust,no_run
/// fn foo() -> i32 {
/// let m = 1;
/// $0
/// let n = 2;
/// let k = 3;
/// k + n
/// $0
/// }
/// ```
///
fn extraction_target(node: &SyntaxNode, selection_range: TextRange) -> Option<FunctionBody> {
if let Some(stmt) = ast::Stmt::cast(node.clone()) {
return match stmt {
ast::Stmt::Item(_) => None,
ast::Stmt::ExprStmt(_) | ast::Stmt::LetStmt(_) => Some(FunctionBody::from_range(
node.parent().and_then(ast::StmtList::cast)?,
node.text_range(),
)),
};
}
// Covering element returned the parent block of one or multiple statements that have been selected
if let Some(stmt_list) = ast::StmtList::cast(node.clone()) {
if let Some(block_expr) = stmt_list.syntax().parent().and_then(ast::BlockExpr::cast) {
if block_expr.syntax().text_range() == selection_range {
return FunctionBody::from_expr(block_expr.into());
}
}
// Extract the full statements.
return Some(FunctionBody::from_range(stmt_list, selection_range));
}
let expr = ast::Expr::cast(node.clone())?;
// A node got selected fully
if node.text_range() == selection_range {
return FunctionBody::from_expr(expr);
}
node.ancestors().find_map(ast::Expr::cast).and_then(FunctionBody::from_expr)
}
#[derive(Debug)]
struct Function {
name: ast::NameRef,
self_param: Option<ast::SelfParam>,
params: Vec<Param>,
control_flow: ControlFlow,
ret_ty: RetType,
body: FunctionBody,
outliving_locals: Vec<OutlivedLocal>,
mods: ContainerInfo,
}
#[derive(Debug)]
struct Param {
var: Local,
ty: hir::Type,
move_local: bool,
requires_mut: bool,
is_copy: bool,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum ParamKind {
Value,
MutValue,
SharedRef,
MutRef,
}
#[derive(Debug, Eq, PartialEq)]
enum FunType {
Unit,
Single(hir::Type),
Tuple(Vec<hir::Type>),
}
/// Where to put extracted function definition
#[derive(Debug)]
enum Anchor {
/// Extract free function and put right after current top-level function
Freestanding,
/// Extract method and put right after current function in the impl-block
Method,
}
// FIXME: ControlFlow and ContainerInfo both track some function modifiers, feels like these two should
// probably be merged somehow.
#[derive(Debug)]
struct ControlFlow {
kind: Option<FlowKind>,
is_async: bool,
is_unsafe: bool,
}
/// The thing whose expression we are extracting from. Can be a function, const, static, const arg, ...
#[derive(Clone, Debug)]
struct ContainerInfo {
is_const: bool,
is_in_tail: bool,
parent_loop: Option<SyntaxNode>,
/// The function's return type, const's type etc.
ret_type: Option<hir::Type>,
}
/// Control flow that is exported from extracted function
///
/// E.g.:
/// ```rust,no_run
/// loop {
/// $0
/// if 42 == 42 {
/// break;
/// }
/// $0
/// }
/// ```
#[derive(Debug, Clone)]
enum FlowKind {
/// Return with value (`return $expr;`)
Return(Option<ast::Expr>),
Try {
kind: TryKind,
},
/// Break with value (`break $expr;`)
Break(Option<ast::Expr>),
/// Continue
Continue,
}
#[derive(Debug, Clone)]
enum TryKind {
Option,
Result { ty: hir::Type },
}
#[derive(Debug)]
enum RetType {
Expr(hir::Type),
Stmt,
}
impl RetType {
fn is_unit(&self) -> bool {
match self {
RetType::Expr(ty) => ty.is_unit(),
RetType::Stmt => true,
}
}
}
/// Semantically same as `ast::Expr`, but preserves identity when using only part of the Block
/// This is the future function body, the part that is being extracted.
#[derive(Debug)]
enum FunctionBody {
Expr(ast::Expr),
Span { parent: ast::StmtList, text_range: TextRange },
}
#[derive(Debug)]
struct OutlivedLocal {
local: Local,
mut_usage_outside_body: bool,
}
/// Container of local variable usages
///
/// Semanticall same as `UsageSearchResult`, but provides more convenient interface
struct LocalUsages(ide_db::search::UsageSearchResult);
impl LocalUsages {
fn find_local_usages(ctx: &AssistContext, var: Local) -> Self {
Self(
Definition::Local(var)
.usages(&ctx.sema)
.in_scope(SearchScope::single_file(ctx.frange.file_id))
.all(),
)
}
fn iter(&self) -> impl Iterator<Item = &FileReference> + '_ {
self.0.iter().flat_map(|(_, rs)| rs)
}
}
impl Function {
fn return_type(&self, ctx: &AssistContext) -> FunType {
match &self.ret_ty {
RetType::Expr(ty) if ty.is_unit() => FunType::Unit,
RetType::Expr(ty) => FunType::Single(ty.clone()),
RetType::Stmt => match self.outliving_locals.as_slice() {
[] => FunType::Unit,
[var] => FunType::Single(var.local.ty(ctx.db())),
vars => {
let types = vars.iter().map(|v| v.local.ty(ctx.db())).collect();
FunType::Tuple(types)
}
},
}
}
}
impl ParamKind {
fn is_ref(&self) -> bool {
matches!(self, ParamKind::SharedRef | ParamKind::MutRef)
}
}
impl Param {
fn kind(&self) -> ParamKind {
match (self.move_local, self.requires_mut, self.is_copy) {
(false, true, _) => ParamKind::MutRef,
(false, false, false) => ParamKind::SharedRef,
(true, true, _) => ParamKind::MutValue,
(_, false, _) => ParamKind::Value,
}
}
fn to_arg(&self, ctx: &AssistContext) -> ast::Expr {
let var = path_expr_from_local(ctx, self.var);
match self.kind() {
ParamKind::Value | ParamKind::MutValue => var,
ParamKind::SharedRef => make::expr_ref(var, false),
ParamKind::MutRef => make::expr_ref(var, true),
}
}
fn to_param(&self, ctx: &AssistContext, module: hir::Module) -> ast::Param {
let var = self.var.name(ctx.db()).unwrap().to_string();
let var_name = make::name(&var);
let pat = match self.kind() {
ParamKind::MutValue => make::ident_pat(false, true, var_name),
ParamKind::Value | ParamKind::SharedRef | ParamKind::MutRef => {
make::ext::simple_ident_pat(var_name)
}
};
let ty = make_ty(&self.ty, ctx, module);
let ty = match self.kind() {
ParamKind::Value | ParamKind::MutValue => ty,
ParamKind::SharedRef => make::ty_ref(ty, false),
ParamKind::MutRef => make::ty_ref(ty, true),
};
make::param(pat.into(), ty)
}
}
impl TryKind {
fn of_ty(ty: hir::Type, ctx: &AssistContext) -> Option<TryKind> {
if ty.is_unknown() {
// We favour Result for `expr?`
return Some(TryKind::Result { ty });
}
let adt = ty.as_adt()?;
let name = adt.name(ctx.db());
// FIXME: use lang items to determine if it is std type or user defined
// E.g. if user happens to define type named `Option`, we would have false positive
match name.to_string().as_str() {
"Option" => Some(TryKind::Option),
"Result" => Some(TryKind::Result { ty }),
_ => None,
}
}
}
impl FlowKind {
fn make_result_handler(&self, expr: Option<ast::Expr>) -> ast::Expr {
match self {
FlowKind::Return(_) => make::expr_return(expr),
FlowKind::Break(_) => make::expr_break(expr),
FlowKind::Try { .. } => {
stdx::never!("cannot have result handler with try");
expr.unwrap_or_else(|| make::expr_return(None))
}
FlowKind::Continue => {
stdx::always!(expr.is_none(), "continue with value is not possible");
make::expr_continue()
}
}
}
fn expr_ty(&self, ctx: &AssistContext) -> Option<hir::Type> {
match self {
FlowKind::Return(Some(expr)) | FlowKind::Break(Some(expr)) => {
ctx.sema.type_of_expr(expr).map(TypeInfo::adjusted)
}
FlowKind::Try { .. } => {
stdx::never!("try does not have defined expr_ty");
None
}
_ => None,
}
}
}
impl FunctionBody {
fn parent(&self) -> Option<SyntaxNode> {
match self {
FunctionBody::Expr(expr) => expr.syntax().parent(),
FunctionBody::Span { parent, .. } => Some(parent.syntax().clone()),
}
}
fn from_expr(expr: ast::Expr) -> Option<Self> {
match expr {
ast::Expr::BreakExpr(it) => it.expr().map(Self::Expr),
ast::Expr::ReturnExpr(it) => it.expr().map(Self::Expr),
ast::Expr::BlockExpr(it) if !it.is_standalone() => None,
expr => Some(Self::Expr(expr)),
}
}
fn from_range(parent: ast::StmtList, selected: TextRange) -> FunctionBody {
let mut text_range = parent
.statements()
.map(|stmt| stmt.syntax().text_range())
.filter(|&stmt| selected.intersect(stmt).filter(|it| !it.is_empty()).is_some())
.fold1(|acc, stmt| acc.cover(stmt));
if let Some(tail_range) = parent
.tail_expr()
.map(|it| it.syntax().text_range())
.filter(|&it| selected.intersect(it).is_some())
{
text_range = Some(match text_range {
Some(text_range) => text_range.cover(tail_range),
None => tail_range,
});
}
Self::Span { parent, text_range: text_range.unwrap_or(selected) }
}
fn indent_level(&self) -> IndentLevel {
match &self {
FunctionBody::Expr(expr) => IndentLevel::from_node(expr.syntax()),
FunctionBody::Span { parent, .. } => IndentLevel::from_node(parent.syntax()) + 1,
}
}
fn tail_expr(&self) -> Option<ast::Expr> {
match &self {
FunctionBody::Expr(expr) => Some(expr.clone()),
FunctionBody::Span { parent, text_range } => {
let tail_expr = parent.tail_expr()?;
text_range.contains_range(tail_expr.syntax().text_range()).then(|| tail_expr)
}
}
}
fn walk_expr(&self, cb: &mut dyn FnMut(ast::Expr)) {
match self {
FunctionBody::Expr(expr) => walk_expr(expr, cb),
FunctionBody::Span { parent, text_range } => {
parent
.statements()
.filter(|stmt| text_range.contains_range(stmt.syntax().text_range()))
.filter_map(|stmt| match stmt {
ast::Stmt::ExprStmt(expr_stmt) => expr_stmt.expr(),
ast::Stmt::Item(_) => None,
ast::Stmt::LetStmt(stmt) => stmt.initializer(),
})
.for_each(|expr| walk_expr(&expr, cb));
if let Some(expr) = parent
.tail_expr()
.filter(|it| text_range.contains_range(it.syntax().text_range()))
{
walk_expr(&expr, cb);
}
}
}
}
fn preorder_expr(&self, cb: &mut dyn FnMut(WalkEvent<ast::Expr>) -> bool) {
match self {
FunctionBody::Expr(expr) => preorder_expr(expr, cb),
FunctionBody::Span { parent, text_range } => {
parent
.statements()
.filter(|stmt| text_range.contains_range(stmt.syntax().text_range()))
.filter_map(|stmt| match stmt {
ast::Stmt::ExprStmt(expr_stmt) => expr_stmt.expr(),
ast::Stmt::Item(_) => None,
ast::Stmt::LetStmt(stmt) => stmt.initializer(),
})
.for_each(|expr| preorder_expr(&expr, cb));
if let Some(expr) = parent
.tail_expr()
.filter(|it| text_range.contains_range(it.syntax().text_range()))
{
preorder_expr(&expr, cb);
}
}
}
}
fn walk_pat(&self, cb: &mut dyn FnMut(ast::Pat)) {
match self {
FunctionBody::Expr(expr) => walk_patterns_in_expr(expr, cb),
FunctionBody::Span { parent, text_range } => {
parent
.statements()
.filter(|stmt| text_range.contains_range(stmt.syntax().text_range()))
.for_each(|stmt| match stmt {
ast::Stmt::ExprStmt(expr_stmt) => {
if let Some(expr) = expr_stmt.expr() {
walk_patterns_in_expr(&expr, cb)
}
}
ast::Stmt::Item(_) => (),
ast::Stmt::LetStmt(stmt) => {
if let Some(pat) = stmt.pat() {
walk_pat(&pat, cb);
}
if let Some(expr) = stmt.initializer() {
walk_patterns_in_expr(&expr, cb);
}
}
});
if let Some(expr) = parent
.tail_expr()
.filter(|it| text_range.contains_range(it.syntax().text_range()))
{
walk_patterns_in_expr(&expr, cb);
}
}
}
}
fn text_range(&self) -> TextRange {
match self {
FunctionBody::Expr(expr) => expr.syntax().text_range(),
&FunctionBody::Span { text_range, .. } => text_range,
}
}
fn contains_range(&self, range: TextRange) -> bool {
self.text_range().contains_range(range)
}
fn precedes_range(&self, range: TextRange) -> bool {
self.text_range().end() <= range.start()
}
fn contains_node(&self, node: &SyntaxNode) -> bool {
self.contains_range(node.text_range())
}
}
impl FunctionBody {
/// Analyzes a function body, returning the used local variables that are referenced in it as well as
/// whether it contains an await expression.
fn analyze(
&self,
sema: &Semantics<RootDatabase>,
) -> (FxIndexSet<Local>, Option<ast::SelfParam>) {
let mut self_param = None;
let mut res = FxIndexSet::default();
let mut cb = |name_ref: Option<_>| {
let local_ref =
match name_ref.and_then(|name_ref| NameRefClass::classify(sema, &name_ref)) {
Some(
NameRefClass::Definition(Definition::Local(local_ref))
| NameRefClass::FieldShorthand { local_ref, field_ref: _ },
) => local_ref,
_ => return,
};
let InFile { file_id, value } = local_ref.source(sema.db);
// locals defined inside macros are not relevant to us
if !file_id.is_macro() {
match value {
Either::Right(it) => {
self_param.replace(it);
}
Either::Left(_) => {
res.insert(local_ref);
}
}
}
};
self.walk_expr(&mut |expr| match expr {
ast::Expr::PathExpr(path_expr) => {
cb(path_expr.path().and_then(|it| it.as_single_name_ref()))
}
ast::Expr::MacroCall(call) => {
if let Some(tt) = call.token_tree() {
tt.syntax()
.children_with_tokens()
.flat_map(SyntaxElement::into_token)
.filter(|it| it.kind() == SyntaxKind::IDENT)
.flat_map(|t| sema.descend_into_macros(t))
.for_each(|t| cb(t.parent().and_then(ast::NameRef::cast)));
}
}
_ => (),
});
(res, self_param)
}
fn analyze_container(&self, sema: &Semantics<RootDatabase>) -> Option<ContainerInfo> {
let mut ancestors = self.parent()?.ancestors();
let infer_expr_opt = |expr| sema.type_of_expr(&expr?).map(TypeInfo::adjusted);
let mut parent_loop = None;
let mut set_parent_loop = |loop_: &dyn ast::HasLoopBody| {
if loop_
.loop_body()
.map_or(false, |it| it.syntax().text_range().contains_range(self.text_range()))
{
parent_loop.get_or_insert(loop_.syntax().clone());
}
};
let (is_const, expr, ty) = loop {
let anc = ancestors.next()?;
break match_ast! {
match anc {
ast::ClosureExpr(closure) => (false, closure.body(), infer_expr_opt(closure.body())),
ast::BlockExpr(block_expr) => {
let (constness, block) = match block_expr.modifier() {
Some(ast::BlockModifier::Const(_)) => (true, block_expr),
Some(ast::BlockModifier::Try(_)) => (false, block_expr),
Some(ast::BlockModifier::Label(label)) if label.lifetime().is_some() => (false, block_expr),
_ => continue,
};
let expr = Some(ast::Expr::BlockExpr(block));
(constness, expr.clone(), infer_expr_opt(expr))
},
ast::Fn(fn_) => {
(fn_.const_token().is_some(), fn_.body().map(ast::Expr::BlockExpr), Some(sema.to_def(&fn_)?.ret_type(sema.db)))
},
ast::Static(statik) => {
(true, statik.body(), Some(sema.to_def(&statik)?.ty(sema.db)))
},
ast::ConstArg(ca) => {
(true, ca.expr(), infer_expr_opt(ca.expr()))
},
ast::Const(konst) => {
(true, konst.body(), Some(sema.to_def(&konst)?.ty(sema.db)))
},
ast::ConstParam(cp) => {
(true, cp.default_val(), Some(sema.to_def(&cp)?.ty(sema.db)))
},
ast::ConstBlockPat(cbp) => {
let expr = cbp.block_expr().map(ast::Expr::BlockExpr);
(true, expr.clone(), infer_expr_opt(expr))
},
ast::Variant(__) => return None,
ast::Meta(__) => return None,
ast::LoopExpr(it) => {
set_parent_loop(&it);
continue;
},
ast::ForExpr(it) => {
set_parent_loop(&it);
continue;
},
ast::WhileExpr(it) => {
set_parent_loop(&it);
continue;
},
_ => continue,
}
};
};
let container_tail = match expr? {
ast::Expr::BlockExpr(block) => block.tail_expr(),
expr => Some(expr),
};
let is_in_tail =
container_tail.zip(self.tail_expr()).map_or(false, |(container_tail, body_tail)| {
container_tail.syntax().text_range().contains_range(body_tail.syntax().text_range())
});
Some(ContainerInfo { is_in_tail, is_const, parent_loop, ret_type: ty })
}
fn return_ty(&self, ctx: &AssistContext) -> Option<RetType> {
match self.tail_expr() {
Some(expr) => ctx.sema.type_of_expr(&expr).map(TypeInfo::original).map(RetType::Expr),
None => Some(RetType::Stmt),
}
}
/// Local variables defined inside `body` that are accessed outside of it
fn ret_values<'a>(
&self,
ctx: &'a AssistContext,
parent: &SyntaxNode,
) -> impl Iterator<Item = OutlivedLocal> + 'a {
let parent = parent.clone();
let range = self.text_range();
locals_defined_in_body(&ctx.sema, self)
.into_iter()
.filter_map(move |local| local_outlives_body(ctx, range, local, &parent))
}
/// Analyses the function body for external control flow.
fn external_control_flow(
&self,
ctx: &AssistContext,
container_info: &ContainerInfo,
) -> Option<ControlFlow> {
let mut ret_expr = None;
let mut try_expr = None;
let mut break_expr = None;
let mut continue_expr = None;
let mut is_async = false;
let mut _is_unsafe = false;
let mut unsafe_depth = 0;
let mut loop_depth = 0;
self.preorder_expr(&mut |expr| {
let expr = match expr {
WalkEvent::Enter(e) => e,
WalkEvent::Leave(expr) => {
match expr {
ast::Expr::LoopExpr(_)
| ast::Expr::ForExpr(_)
| ast::Expr::WhileExpr(_) => loop_depth -= 1,
ast::Expr::BlockExpr(block_expr) if block_expr.unsafe_token().is_some() => {
unsafe_depth -= 1
}
_ => (),
}
return false;
}
};
match expr {
ast::Expr::LoopExpr(_) | ast::Expr::ForExpr(_) | ast::Expr::WhileExpr(_) => {
loop_depth += 1;
}
ast::Expr::BlockExpr(block_expr) if block_expr.unsafe_token().is_some() => {
unsafe_depth += 1
}
ast::Expr::ReturnExpr(it) => {
ret_expr = Some(it);
}
ast::Expr::TryExpr(it) => {
try_expr = Some(it);
}
ast::Expr::BreakExpr(it) if loop_depth == 0 => {
break_expr = Some(it);
}
ast::Expr::ContinueExpr(it) if loop_depth == 0 => {
continue_expr = Some(it);
}
ast::Expr::AwaitExpr(_) => is_async = true,
// FIXME: Do unsafe analysis on expression, sem highlighting knows this so we should be able
// to just lift that out of there
// expr if unsafe_depth ==0 && expr.is_unsafe => is_unsafe = true,
_ => {}
}
false
});
let kind = match (try_expr, ret_expr, break_expr, continue_expr) {
(Some(_), _, None, None) => {
let ret_ty = container_info.ret_type.clone()?;
let kind = TryKind::of_ty(ret_ty, ctx)?;
Some(FlowKind::Try { kind })
}
(Some(_), _, _, _) => {
cov_mark::hit!(external_control_flow_try_and_bc);
return None;
}
(None, Some(r), None, None) => Some(FlowKind::Return(r.expr())),
(None, Some(_), _, _) => {
cov_mark::hit!(external_control_flow_return_and_bc);
return None;
}
(None, None, Some(_), Some(_)) => {
cov_mark::hit!(external_control_flow_break_and_continue);
return None;
}
(None, None, Some(b), None) => Some(FlowKind::Break(b.expr())),
(None, None, None, Some(_)) => Some(FlowKind::Continue),
(None, None, None, None) => None,
};
Some(ControlFlow { kind, is_async, is_unsafe: _is_unsafe })
}
/// find variables that should be extracted as params
///
/// Computes additional info that affects param type and mutability
fn extracted_function_params(
&self,
ctx: &AssistContext,
container_info: &ContainerInfo,
locals: impl Iterator<Item = Local>,
) -> Vec<Param> {
locals
.map(|local| (local, local.source(ctx.db())))
.filter(|(_, src)| is_defined_outside_of_body(ctx, self, src))
.filter_map(|(local, src)| match src.value {
Either::Left(src) => Some((local, src)),
Either::Right(_) => {
stdx::never!(false, "Local::is_self returned false, but source is SelfParam");
None
}
})
.map(|(var, src)| {
let usages = LocalUsages::find_local_usages(ctx, var);
let ty = var.ty(ctx.db());
let defined_outside_parent_loop = container_info
.parent_loop
.as_ref()
.map_or(true, |it| it.text_range().contains_range(src.syntax().text_range()));
let is_copy = ty.is_copy(ctx.db());
let has_usages = self.has_usages_after_body(&usages);
let requires_mut =
!ty.is_mutable_reference() && has_exclusive_usages(ctx, &usages, self);
// We can move the value into the function call if it's not used after the call,
// if the var is not used but defined outside a loop we are extracting from we can't move it either
// as the function will reuse it in the next iteration.
let move_local = !has_usages && defined_outside_parent_loop;
Param { var, ty, move_local, requires_mut, is_copy }
})
.collect()
}
fn has_usages_after_body(&self, usages: &LocalUsages) -> bool {
usages.iter().any(|reference| self.precedes_range(reference.range))
}
}
/// checks if relevant var is used with `&mut` access inside body
fn has_exclusive_usages(ctx: &AssistContext, usages: &LocalUsages, body: &FunctionBody) -> bool {
usages
.iter()
.filter(|reference| body.contains_range(reference.range))
.any(|reference| reference_is_exclusive(reference, body, ctx))
}
/// checks if this reference requires `&mut` access inside node
fn reference_is_exclusive(
reference: &FileReference,
node: &dyn HasTokenAtOffset,
ctx: &AssistContext,
) -> bool {
// we directly modify variable with set: `n = 0`, `n += 1`
if reference.category == Some(ReferenceCategory::Write) {
return true;
}
// we take `&mut` reference to variable: `&mut v`
let path = match path_element_of_reference(node, reference) {
Some(path) => path,
None => return false,
};
expr_require_exclusive_access(ctx, &path).unwrap_or(false)
}
/// checks if this expr requires `&mut` access, recurses on field access
fn expr_require_exclusive_access(ctx: &AssistContext, expr: &ast::Expr) -> Option<bool> {
if let ast::Expr::MacroCall(_) = expr {
// FIXME: expand macro and check output for mutable usages of the variable?
return None;
}
let parent = expr.syntax().parent()?;
if let Some(bin_expr) = ast::BinExpr::cast(parent.clone()) {
if matches!(bin_expr.op_kind()?, ast::BinaryOp::Assignment { .. }) {
return Some(bin_expr.lhs()?.syntax() == expr.syntax());
}
return Some(false);
}
if let Some(ref_expr) = ast::RefExpr::cast(parent.clone()) {
return Some(ref_expr.mut_token().is_some());
}
if let Some(method_call) = ast::MethodCallExpr::cast(parent.clone()) {
let func = ctx.sema.resolve_method_call(&method_call)?;
let self_param = func.self_param(ctx.db())?;
let access = self_param.access(ctx.db());
return Some(matches!(access, hir::Access::Exclusive));
}
if let Some(field) = ast::FieldExpr::cast(parent) {
return expr_require_exclusive_access(ctx, &field.into());
}
Some(false)
}
trait HasTokenAtOffset {
fn token_at_offset(&self, offset: TextSize) -> TokenAtOffset<SyntaxToken>;
}
impl HasTokenAtOffset for SyntaxNode {
fn token_at_offset(&self, offset: TextSize) -> TokenAtOffset<SyntaxToken> {
SyntaxNode::token_at_offset(self, offset)
}
}
impl HasTokenAtOffset for FunctionBody {
fn token_at_offset(&self, offset: TextSize) -> TokenAtOffset<SyntaxToken> {
match self {
FunctionBody::Expr(expr) => expr.syntax().token_at_offset(offset),
FunctionBody::Span { parent, text_range } => {
match parent.syntax().token_at_offset(offset) {
TokenAtOffset::None => TokenAtOffset::None,
TokenAtOffset::Single(t) => {
if text_range.contains_range(t.text_range()) {
TokenAtOffset::Single(t)
} else {
TokenAtOffset::None
}
}
TokenAtOffset::Between(a, b) => {
match (
text_range.contains_range(a.text_range()),
text_range.contains_range(b.text_range()),
) {
(true, true) => TokenAtOffset::Between(a, b),
(true, false) => TokenAtOffset::Single(a),
(false, true) => TokenAtOffset::Single(b),
(false, false) => TokenAtOffset::None,
}
}
}
}
}
}
}
/// find relevant `ast::Expr` for reference
///
/// # Preconditions
///
/// `node` must cover `reference`, that is `node.text_range().contains_range(reference.range)`
fn path_element_of_reference(
node: &dyn HasTokenAtOffset,
reference: &FileReference,
) -> Option<ast::Expr> {
let token = node.token_at_offset(reference.range.start()).right_biased().or_else(|| {
stdx::never!(false, "cannot find token at variable usage: {:?}", reference);
None
})?;
let path = token.ancestors().find_map(ast::Expr::cast).or_else(|| {
stdx::never!(false, "cannot find path parent of variable usage: {:?}", token);
None
})?;
stdx::always!(
matches!(path, ast::Expr::PathExpr(_) | ast::Expr::MacroCall(_)),
"unexpected expression type for variable usage: {:?}",
path
);
Some(path)
}
/// list local variables defined inside `body`
fn locals_defined_in_body(
sema: &Semantics<RootDatabase>,
body: &FunctionBody,
) -> FxIndexSet<Local> {
// FIXME: this doesn't work well with macros
// see https://github.com/rust-analyzer/rust-analyzer/pull/7535#discussion_r570048550
let mut res = FxIndexSet::default();
body.walk_pat(&mut |pat| {
if let ast::Pat::IdentPat(pat) = pat {
if let Some(local) = sema.to_def(&pat) {
res.insert(local);
}
}
});
res
}
/// Returns usage details if local variable is used after(outside of) body
fn local_outlives_body(
ctx: &AssistContext,
body_range: TextRange,
local: Local,
parent: &SyntaxNode,
) -> Option<OutlivedLocal> {
let usages = LocalUsages::find_local_usages(ctx, local);
let mut has_mut_usages = false;
let mut any_outlives = false;
for usage in usages.iter() {
if body_range.end() <= usage.range.start() {
has_mut_usages |= reference_is_exclusive(usage, parent, ctx);
any_outlives |= true;
if has_mut_usages {
break; // no need to check more elements we have all the info we wanted
}
}
}
if !any_outlives {
return None;
}
Some(OutlivedLocal { local, mut_usage_outside_body: has_mut_usages })
}
/// checks if the relevant local was defined before(outside of) body
fn is_defined_outside_of_body(
ctx: &AssistContext,
body: &FunctionBody,
src: &hir::InFile<Either<ast::IdentPat, ast::SelfParam>>,
) -> bool {
src.file_id.original_file(ctx.db()) == ctx.frange.file_id
&& !body.contains_node(either_syntax(&src.value))
}
fn either_syntax(value: &Either<ast::IdentPat, ast::SelfParam>) -> &SyntaxNode {
match value {
Either::Left(pat) => pat.syntax(),
Either::Right(it) => it.syntax(),
}
}
/// find where to put extracted function definition
///
/// Function should be put right after returned node
fn node_to_insert_after(body: &FunctionBody, anchor: Anchor) -> Option<SyntaxNode> {
let node = match body {
FunctionBody::Expr(e) => e.syntax(),
FunctionBody::Span { parent, .. } => parent.syntax(),
};
let mut ancestors = node.ancestors().peekable();
let mut last_ancestor = None;
while let Some(next_ancestor) = ancestors.next() {
match next_ancestor.kind() {
SyntaxKind::SOURCE_FILE => break,
SyntaxKind::ITEM_LIST if !matches!(anchor, Anchor::Freestanding) => continue,
SyntaxKind::ITEM_LIST => {
if ancestors.peek().map(SyntaxNode::kind) == Some(SyntaxKind::MODULE) {
break;
}
}
SyntaxKind::ASSOC_ITEM_LIST if !matches!(anchor, Anchor::Method) => {
continue;
}
SyntaxKind::ASSOC_ITEM_LIST => {
if ancestors.peek().map(SyntaxNode::kind) == Some(SyntaxKind::IMPL) {
break;
}
}
_ => (),
}
last_ancestor = Some(next_ancestor);
}
last_ancestor
}
fn make_call(ctx: &AssistContext, fun: &Function, indent: IndentLevel) -> String {
let ret_ty = fun.return_type(ctx);
let args = make::arg_list(fun.params.iter().map(|param| param.to_arg(ctx)));
let name = fun.name.clone();
let mut call_expr = if fun.self_param.is_some() {
let self_arg = make::expr_path(make::ext::ident_path("self"));
make::expr_method_call(self_arg, name, args)
} else {
let func = make::expr_path(make::path_unqualified(make::path_segment(name)));
make::expr_call(func, args)
};
let handler = FlowHandler::from_ret_ty(fun, &ret_ty);
if fun.control_flow.is_async {
call_expr = make::expr_await(call_expr);
}
let expr = handler.make_call_expr(call_expr).indent(indent);
let mut_modifier = |var: &OutlivedLocal| if var.mut_usage_outside_body { "mut " } else { "" };
let mut buf = String::new();
match fun.outliving_locals.as_slice() {
[] => {}
[var] => {
format_to!(buf, "let {}{} = ", mut_modifier(var), var.local.name(ctx.db()).unwrap())
}
vars => {
buf.push_str("let (");
let bindings = vars.iter().format_with(", ", |local, f| {
f(&format_args!("{}{}", mut_modifier(local), local.local.name(ctx.db()).unwrap()))
});
format_to!(buf, "{}", bindings);
buf.push_str(") = ");
}
}
format_to!(buf, "{}", expr);
let insert_comma = fun
.body
.parent()
.and_then(ast::MatchArm::cast)
.map_or(false, |it| it.comma_token().is_none());
if insert_comma {
buf.push(',');
} else if fun.ret_ty.is_unit() && (!fun.outliving_locals.is_empty() || !expr.is_block_like()) {
buf.push(';');
}
buf
}
enum FlowHandler {
None,
Try { kind: TryKind },
If { action: FlowKind },
IfOption { action: FlowKind },
MatchOption { none: FlowKind },
MatchResult { err: FlowKind },
}
impl FlowHandler {
fn from_ret_ty(fun: &Function, ret_ty: &FunType) -> FlowHandler {
match &fun.control_flow.kind {
None => FlowHandler::None,
Some(flow_kind) => {
let action = flow_kind.clone();
if *ret_ty == FunType::Unit {
match flow_kind {
FlowKind::Return(None) | FlowKind::Break(None) | FlowKind::Continue => {
FlowHandler::If { action }
}
FlowKind::Return(_) | FlowKind::Break(_) => {
FlowHandler::IfOption { action }
}
FlowKind::Try { kind } => FlowHandler::Try { kind: kind.clone() },
}
} else {
match flow_kind {
FlowKind::Return(None) | FlowKind::Break(None) | FlowKind::Continue => {
FlowHandler::MatchOption { none: action }
}
FlowKind::Return(_) | FlowKind::Break(_) => {
FlowHandler::MatchResult { err: action }
}
FlowKind::Try { kind } => FlowHandler::Try { kind: kind.clone() },
}
}
}
}
}
fn make_call_expr(&self, call_expr: ast::Expr) -> ast::Expr {
match self {
FlowHandler::None => call_expr,
FlowHandler::Try { kind: _ } => make::expr_try(call_expr),
FlowHandler::If { action } => {
let action = action.make_result_handler(None);
let stmt = make::expr_stmt(action);
let block = make::block_expr(iter::once(stmt.into()), None);
let condition = make::condition(call_expr, None);
make::expr_if(condition, block, None)
}
FlowHandler::IfOption { action } => {
let path = make::ext::ident_path("Some");
let value_pat = make::ext::simple_ident_pat(make::name("value"));
let pattern = make::tuple_struct_pat(path, iter::once(value_pat.into()));
let cond = make::condition(call_expr, Some(pattern.into()));
let value = make::expr_path(make::ext::ident_path("value"));
let action_expr = action.make_result_handler(Some(value));
let action_stmt = make::expr_stmt(action_expr);
let then = make::block_expr(iter::once(action_stmt.into()), None);
make::expr_if(cond, then, None)
}
FlowHandler::MatchOption { none } => {
let some_name = "value";
let some_arm = {
let path = make::ext::ident_path("Some");
let value_pat = make::ext::simple_ident_pat(make::name(some_name));
let pat = make::tuple_struct_pat(path, iter::once(value_pat.into()));
let value = make::expr_path(make::ext::ident_path(some_name));
make::match_arm(iter::once(pat.into()), None, value)
};
let none_arm = {
let path = make::ext::ident_path("None");
let pat = make::path_pat(path);
make::match_arm(iter::once(pat), None, none.make_result_handler(None))
};
let arms = make::match_arm_list(vec![some_arm, none_arm]);
make::expr_match(call_expr, arms)
}
FlowHandler::MatchResult { err } => {
let ok_name = "value";
let err_name = "value";
let ok_arm = {
let path = make::ext::ident_path("Ok");
let value_pat = make::ext::simple_ident_pat(make::name(ok_name));
let pat = make::tuple_struct_pat(path, iter::once(value_pat.into()));
let value = make::expr_path(make::ext::ident_path(ok_name));
make::match_arm(iter::once(pat.into()), None, value)
};
let err_arm = {
let path = make::ext::ident_path("Err");
let value_pat = make::ext::simple_ident_pat(make::name(err_name));
let pat = make::tuple_struct_pat(path, iter::once(value_pat.into()));
let value = make::expr_path(make::ext::ident_path(err_name));
make::match_arm(
iter::once(pat.into()),
None,
err.make_result_handler(Some(value)),
)
};
let arms = make::match_arm_list(vec![ok_arm, err_arm]);
make::expr_match(call_expr, arms)
}
}
}
}
fn path_expr_from_local(ctx: &AssistContext, var: Local) -> ast::Expr {
let name = var.name(ctx.db()).unwrap().to_string();
make::expr_path(make::ext::ident_path(&name))
}
fn format_function(
ctx: &AssistContext,
module: hir::Module,
fun: &Function,
old_indent: IndentLevel,
new_indent: IndentLevel,
) -> String {
let mut fn_def = String::new();
let params = fun.make_param_list(ctx, module);
let ret_ty = fun.make_ret_ty(ctx, module);
let body = make_body(ctx, old_indent, new_indent, fun);
let const_kw = if fun.mods.is_const { "const " } else { "" };
let async_kw = if fun.control_flow.is_async { "async " } else { "" };
let unsafe_kw = if fun.control_flow.is_unsafe { "unsafe " } else { "" };
match ctx.config.snippet_cap {
Some(_) => format_to!(
fn_def,
"\n\n{}{}{}{}fn $0{}{}",
new_indent,
const_kw,
async_kw,
unsafe_kw,
fun.name,
params
),
None => format_to!(
fn_def,
"\n\n{}{}{}{}fn {}{}",
new_indent,
const_kw,
async_kw,
unsafe_kw,
fun.name,
params
),
}
if let Some(ret_ty) = ret_ty {
format_to!(fn_def, " {}", ret_ty);
}
format_to!(fn_def, " {}", body);
fn_def
}
impl Function {
fn make_param_list(&self, ctx: &AssistContext, module: hir::Module) -> ast::ParamList {
let self_param = self.self_param.clone();
let params = self.params.iter().map(|param| param.to_param(ctx, module));
make::param_list(self_param, params)
}
fn make_ret_ty(&self, ctx: &AssistContext, module: hir::Module) -> Option<ast::RetType> {
let fun_ty = self.return_type(ctx);
let handler = if self.mods.is_in_tail {
FlowHandler::None
} else {
FlowHandler::from_ret_ty(self, &fun_ty)
};
let ret_ty = match &handler {
FlowHandler::None => {
if matches!(fun_ty, FunType::Unit) {
return None;
}
fun_ty.make_ty(ctx, module)
}
FlowHandler::Try { kind: TryKind::Option } => {
make::ext::ty_option(fun_ty.make_ty(ctx, module))
}
FlowHandler::Try { kind: TryKind::Result { ty: parent_ret_ty } } => {
let handler_ty = parent_ret_ty
.type_arguments()
.nth(1)
.map(|ty| make_ty(&ty, ctx, module))
.unwrap_or_else(make::ty_placeholder);
make::ext::ty_result(fun_ty.make_ty(ctx, module), handler_ty)
}
FlowHandler::If { .. } => make::ext::ty_bool(),
FlowHandler::IfOption { action } => {
let handler_ty = action
.expr_ty(ctx)
.map(|ty| make_ty(&ty, ctx, module))
.unwrap_or_else(make::ty_placeholder);
make::ext::ty_option(handler_ty)
}
FlowHandler::MatchOption { .. } => make::ext::ty_option(fun_ty.make_ty(ctx, module)),
FlowHandler::MatchResult { err } => {
let handler_ty = err
.expr_ty(ctx)
.map(|ty| make_ty(&ty, ctx, module))
.unwrap_or_else(make::ty_placeholder);
make::ext::ty_result(fun_ty.make_ty(ctx, module), handler_ty)
}
};
Some(make::ret_type(ret_ty))
}
}
impl FunType {
fn make_ty(&self, ctx: &AssistContext, module: hir::Module) -> ast::Type {
match self {
FunType::Unit => make::ty_unit(),
FunType::Single(ty) => make_ty(ty, ctx, module),
FunType::Tuple(types) => match types.as_slice() {
[] => {
stdx::never!("tuple type with 0 elements");
make::ty_unit()
}
[ty] => {
stdx::never!("tuple type with 1 element");
make_ty(ty, ctx, module)
}
types => {
let types = types.iter().map(|ty| make_ty(ty, ctx, module));
make::ty_tuple(types)
}
},
}
}
}
fn make_body(
ctx: &AssistContext,
old_indent: IndentLevel,
new_indent: IndentLevel,
fun: &Function,
) -> ast::BlockExpr {
let ret_ty = fun.return_type(ctx);
let handler = if fun.mods.is_in_tail {
FlowHandler::None
} else {
FlowHandler::from_ret_ty(fun, &ret_ty)
};
let block = match &fun.body {
FunctionBody::Expr(expr) => {
let expr = rewrite_body_segment(ctx, &fun.params, &handler, expr.syntax());
let expr = ast::Expr::cast(expr).unwrap();
match expr {
ast::Expr::BlockExpr(block) => {
// If the extracted expression is itself a block, there is no need to wrap it inside another block.
let block = block.dedent(old_indent);
// Recreate the block for formatting consistency with other extracted functions.
make::block_expr(block.statements(), block.tail_expr())
}
_ => {
let expr = expr.dedent(old_indent).indent(IndentLevel(1));
make::block_expr(Vec::new(), Some(expr))
}
}
}
FunctionBody::Span { parent, text_range } => {
let mut elements: Vec<_> = parent
.syntax()
.children()
.filter(|it| text_range.contains_range(it.text_range()))
.map(|it| rewrite_body_segment(ctx, &fun.params, &handler, &it))
.collect();
let mut tail_expr = match elements.pop() {
Some(node) => ast::Expr::cast(node.clone()).or_else(|| {
elements.push(node);
None
}),
None => None,
};
if tail_expr.is_none() {
match fun.outliving_locals.as_slice() {
[] => {}
[var] => {
tail_expr = Some(path_expr_from_local(ctx, var.local));
}
vars => {
let exprs = vars.iter().map(|var| path_expr_from_local(ctx, var.local));
let expr = make::expr_tuple(exprs);
tail_expr = Some(expr);
}
}
}
let elements = elements.into_iter().filter_map(|node| match ast::Stmt::cast(node) {
Some(stmt) => Some(stmt),
None => {
stdx::never!("block contains non-statement");
None
}
});
let body_indent = IndentLevel(1);
let elements = elements.map(|stmt| stmt.dedent(old_indent).indent(body_indent));
let tail_expr = tail_expr.map(|expr| expr.dedent(old_indent).indent(body_indent));
make::block_expr(elements, tail_expr)
}
};
let block = match &handler {
FlowHandler::None => block,
FlowHandler::Try { kind } => {
let block = with_default_tail_expr(block, make::expr_unit());
map_tail_expr(block, |tail_expr| {
let constructor = match kind {
TryKind::Option => "Some",
TryKind::Result { .. } => "Ok",
};
let func = make::expr_path(make::ext::ident_path(constructor));
let args = make::arg_list(iter::once(tail_expr));
make::expr_call(func, args)
})
}
FlowHandler::If { .. } => {
let lit_false = make::expr_literal("false");
with_tail_expr(block, lit_false.into())
}
FlowHandler::IfOption { .. } => {
let none = make::expr_path(make::ext::ident_path("None"));
with_tail_expr(block, none)
}
FlowHandler::MatchOption { .. } => map_tail_expr(block, |tail_expr| {
let some = make::expr_path(make::ext::ident_path("Some"));
let args = make::arg_list(iter::once(tail_expr));
make::expr_call(some, args)
}),
FlowHandler::MatchResult { .. } => map_tail_expr(block, |tail_expr| {
let ok = make::expr_path(make::ext::ident_path("Ok"));
let args = make::arg_list(iter::once(tail_expr));
make::expr_call(ok, args)
}),
};
block.indent(new_indent)
}
fn map_tail_expr(block: ast::BlockExpr, f: impl FnOnce(ast::Expr) -> ast::Expr) -> ast::BlockExpr {
let tail_expr = match block.tail_expr() {
Some(tail_expr) => tail_expr,
None => return block,
};
make::block_expr(block.statements(), Some(f(tail_expr)))
}
fn with_default_tail_expr(block: ast::BlockExpr, tail_expr: ast::Expr) -> ast::BlockExpr {
match block.tail_expr() {
Some(_) => block,
None => make::block_expr(block.statements(), Some(tail_expr)),
}
}
fn with_tail_expr(block: ast::BlockExpr, tail_expr: ast::Expr) -> ast::BlockExpr {
let stmt_tail = block.tail_expr().map(|expr| make::expr_stmt(expr).into());
let stmts = block.statements().chain(stmt_tail);
make::block_expr(stmts, Some(tail_expr))
}
fn format_type(ty: &hir::Type, ctx: &AssistContext, module: hir::Module) -> String {
ty.display_source_code(ctx.db(), module.into()).ok().unwrap_or_else(|| "_".to_string())
}
fn make_ty(ty: &hir::Type, ctx: &AssistContext, module: hir::Module) -> ast::Type {
let ty_str = format_type(ty, ctx, module);
make::ty(&ty_str)
}
fn rewrite_body_segment(
ctx: &AssistContext,
params: &[Param],
handler: &FlowHandler,
syntax: &SyntaxNode,
) -> SyntaxNode {
let syntax = fix_param_usages(ctx, params, syntax);
update_external_control_flow(handler, &syntax);
syntax
}
/// change all usages to account for added `&`/`&mut` for some params
fn fix_param_usages(ctx: &AssistContext, params: &[Param], syntax: &SyntaxNode) -> SyntaxNode {
let mut usages_for_param: Vec<(&Param, Vec<ast::Expr>)> = Vec::new();
let tm = TreeMutator::new(syntax);
for param in params {
if !param.kind().is_ref() {
continue;
}
let usages = LocalUsages::find_local_usages(ctx, param.var);
let usages = usages
.iter()
.filter(|reference| syntax.text_range().contains_range(reference.range))
.filter_map(|reference| path_element_of_reference(syntax, reference))
.map(|expr| tm.make_mut(&expr));
usages_for_param.push((param, usages.collect()));
}
let res = tm.make_syntax_mut(syntax);
for (param, usages) in usages_for_param {
for usage in usages {
match usage.syntax().ancestors().skip(1).find_map(ast::Expr::cast) {
Some(ast::Expr::MethodCallExpr(_) | ast::Expr::FieldExpr(_)) => {
// do nothing
}
Some(ast::Expr::RefExpr(node))
if param.kind() == ParamKind::MutRef && node.mut_token().is_some() =>
{
ted::replace(node.syntax(), node.expr().unwrap().syntax());
}
Some(ast::Expr::RefExpr(node))
if param.kind() == ParamKind::SharedRef && node.mut_token().is_none() =>
{
ted::replace(node.syntax(), node.expr().unwrap().syntax());
}
Some(_) | None => {
let p = &make::expr_prefix(T![*], usage.clone()).clone_for_update();
ted::replace(usage.syntax(), p.syntax())
}
}
}
}
res
}
fn update_external_control_flow(handler: &FlowHandler, syntax: &SyntaxNode) {
let mut nested_loop = None;
let mut nested_scope = None;
for event in syntax.preorder() {
match event {
WalkEvent::Enter(e) => match e.kind() {
SyntaxKind::LOOP_EXPR | SyntaxKind::WHILE_EXPR | SyntaxKind::FOR_EXPR => {
if nested_loop.is_none() {
nested_loop = Some(e.clone());
}
}
SyntaxKind::FN
| SyntaxKind::CONST
| SyntaxKind::STATIC
| SyntaxKind::IMPL
| SyntaxKind::MODULE => {
if nested_scope.is_none() {
nested_scope = Some(e.clone());
}
}
_ => {}
},
WalkEvent::Leave(e) => {
if nested_scope.is_none() {
if let Some(expr) = ast::Expr::cast(e.clone()) {
match expr {
ast::Expr::ReturnExpr(return_expr) if nested_scope.is_none() => {
let expr = return_expr.expr();
if let Some(replacement) = make_rewritten_flow(handler, expr) {
ted::replace(return_expr.syntax(), replacement.syntax())
}
}
ast::Expr::BreakExpr(break_expr) if nested_loop.is_none() => {
let expr = break_expr.expr();
if let Some(replacement) = make_rewritten_flow(handler, expr) {
ted::replace(break_expr.syntax(), replacement.syntax())
}
}
ast::Expr::ContinueExpr(continue_expr) if nested_loop.is_none() => {
if let Some(replacement) = make_rewritten_flow(handler, None) {
ted::replace(continue_expr.syntax(), replacement.syntax())
}
}
_ => {
// do nothing
}
}
}
}
if nested_loop.as_ref() == Some(&e) {
nested_loop = None;
}
if nested_scope.as_ref() == Some(&e) {
nested_scope = None;
}
}
};
}
}
fn make_rewritten_flow(handler: &FlowHandler, arg_expr: Option<ast::Expr>) -> Option<ast::Expr> {
let value = match handler {
FlowHandler::None | FlowHandler::Try { .. } => return None,
FlowHandler::If { .. } => make::expr_literal("true").into(),
FlowHandler::IfOption { .. } => {
let expr = arg_expr.unwrap_or_else(|| make::expr_tuple(Vec::new()));
let args = make::arg_list(iter::once(expr));
make::expr_call(make::expr_path(make::ext::ident_path("Some")), args)
}
FlowHandler::MatchOption { .. } => make::expr_path(make::ext::ident_path("None")),
FlowHandler::MatchResult { .. } => {
let expr = arg_expr.unwrap_or_else(|| make::expr_tuple(Vec::new()));
let args = make::arg_list(iter::once(expr));
make::expr_call(make::expr_path(make::ext::ident_path("Err")), args)
}
};
Some(make::expr_return(Some(value)).clone_for_update())
}
#[cfg(test)]
mod tests {
use crate::tests::{check_assist, check_assist_not_applicable};
use super::*;
#[test]
fn no_args_from_binary_expr() {
check_assist(
extract_function,
r#"
fn foo() {
foo($01 + 1$0);
}
"#,
r#"
fn foo() {
foo(fun_name());
}
fn $0fun_name() -> i32 {
1 + 1
}
"#,
);
}
#[test]
fn no_args_from_binary_expr_in_module() {
check_assist(
extract_function,
r#"
mod bar {
fn foo() {
foo($01 + 1$0);
}
}
"#,
r#"
mod bar {
fn foo() {
foo(fun_name());
}
fn $0fun_name() -> i32 {
1 + 1
}
}
"#,
);
}
#[test]
fn no_args_from_binary_expr_indented() {
check_assist(
extract_function,
r#"
fn foo() {
$0{ 1 + 1 }$0;
}
"#,
r#"
fn foo() {
fun_name();
}
fn $0fun_name() -> i32 {
1 + 1
}
"#,
);
}
#[test]
fn no_args_from_stmt_with_last_expr() {
check_assist(
extract_function,
r#"
fn foo() -> i32 {
let k = 1;
$0let m = 1;
m + 1$0
}
"#,
r#"
fn foo() -> i32 {
let k = 1;
fun_name()
}
fn $0fun_name() -> i32 {
let m = 1;
m + 1
}
"#,
);
}
#[test]
fn no_args_from_stmt_unit() {
check_assist(
extract_function,
r#"
fn foo() {
let k = 3;
$0let m = 1;
let n = m + 1;$0
let g = 5;
}
"#,
r#"
fn foo() {
let k = 3;
fun_name();
let g = 5;
}
fn $0fun_name() {
let m = 1;
let n = m + 1;
}
"#,
);
}
#[test]
fn no_args_if() {
check_assist(
extract_function,
r#"
fn foo() {
$0if true { }$0
}
"#,
r#"
fn foo() {
fun_name();
}
fn $0fun_name() {
if true { }
}
"#,
);
}
#[test]
fn no_args_if_else() {
check_assist(
extract_function,
r#"
fn foo() -> i32 {
$0if true { 1 } else { 2 }$0
}
"#,
r#"
fn foo() -> i32 {
fun_name()
}
fn $0fun_name() -> i32 {
if true { 1 } else { 2 }
}
"#,
);
}
#[test]
fn no_args_if_let_else() {
check_assist(
extract_function,
r#"
fn foo() -> i32 {
$0if let true = false { 1 } else { 2 }$0
}
"#,
r#"
fn foo() -> i32 {
fun_name()
}
fn $0fun_name() -> i32 {
if let true = false { 1 } else { 2 }
}
"#,
);
}
#[test]
fn no_args_match() {
check_assist(
extract_function,
r#"
fn foo() -> i32 {
$0match true {
true => 1,
false => 2,
}$0
}
"#,
r#"
fn foo() -> i32 {
fun_name()
}
fn $0fun_name() -> i32 {
match true {
true => 1,
false => 2,
}
}
"#,
);
}
#[test]
fn no_args_while() {
check_assist(
extract_function,
r#"
fn foo() {
$0while true { }$0
}
"#,
r#"
fn foo() {
fun_name();
}
fn $0fun_name() {
while true { }
}
"#,
);
}
#[test]
fn no_args_for() {
check_assist(
extract_function,
r#"
fn foo() {
$0for v in &[0, 1] { }$0
}
"#,
r#"
fn foo() {
fun_name();
}
fn $0fun_name() {
for v in &[0, 1] { }
}
"#,
);
}
#[test]
fn no_args_from_loop_unit() {
check_assist(
extract_function,
r#"
fn foo() {
$0loop {
let m = 1;
}$0
}
"#,
r#"
fn foo() {
fun_name()
}
fn $0fun_name() -> ! {
loop {
let m = 1;
}
}
"#,
);
}
#[test]
fn no_args_from_loop_with_return() {
check_assist(
extract_function,
r#"
fn foo() {
let v = $0loop {
let m = 1;
break m;
}$0;
}
"#,
r#"
fn foo() {
let v = fun_name();
}
fn $0fun_name() -> i32 {
loop {
let m = 1;
break m;
}
}
"#,
);
}
#[test]
fn no_args_from_match() {
check_assist(
extract_function,
r#"
fn foo() {
let v: i32 = $0match Some(1) {
Some(x) => x,
None => 0,
}$0;
}
"#,
r#"
fn foo() {
let v: i32 = fun_name();
}
fn $0fun_name() -> i32 {
match Some(1) {
Some(x) => x,
None => 0,
}
}
"#,
);
}
#[test]
fn extract_partial_block_single_line() {
check_assist(
extract_function,
r#"
fn foo() {
let n = 1;
let mut v = $0n * n;$0
v += 1;
}
"#,
r#"
fn foo() {
let n = 1;
let mut v = fun_name(n);
v += 1;
}
fn $0fun_name(n: i32) -> i32 {
let mut v = n * n;
v
}
"#,
);
}
#[test]
fn extract_partial_block() {
check_assist(
extract_function,
r#"
fn foo() {
let m = 2;
let n = 1;
let mut v = m $0* n;
let mut w = 3;$0
v += 1;
w += 1;
}
"#,
r#"
fn foo() {
let m = 2;
let n = 1;
let (mut v, mut w) = fun_name(m, n);
v += 1;
w += 1;
}
fn $0fun_name(m: i32, n: i32) -> (i32, i32) {
let mut v = m * n;
let mut w = 3;
(v, w)
}
"#,
);
}
#[test]
fn argument_form_expr() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
let n = 2;
$0n+2$0
}
"#,
r#"
fn foo() -> u32 {
let n = 2;
fun_name(n)
}
fn $0fun_name(n: u32) -> u32 {
n+2
}
"#,
)
}
#[test]
fn argument_used_twice_form_expr() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
let n = 2;
$0n+n$0
}
"#,
r#"
fn foo() -> u32 {
let n = 2;
fun_name(n)
}
fn $0fun_name(n: u32) -> u32 {
n+n
}
"#,
)
}
#[test]
fn two_arguments_form_expr() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
let n = 2;
let m = 3;
$0n+n*m$0
}
"#,
r#"
fn foo() -> u32 {
let n = 2;
let m = 3;
fun_name(n, m)
}
fn $0fun_name(n: u32, m: u32) -> u32 {
n+n*m
}
"#,
)
}
#[test]
fn argument_and_locals() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
let n = 2;
$0let m = 1;
n + m$0
}
"#,
r#"
fn foo() -> u32 {
let n = 2;
fun_name(n)
}
fn $0fun_name(n: u32) -> u32 {
let m = 1;
n + m
}
"#,
)
}
#[test]
fn in_comment_is_not_applicable() {
cov_mark::check!(extract_function_in_comment_is_not_applicable);
check_assist_not_applicable(extract_function, r"fn main() { 1 + /* $0comment$0 */ 1; }");
}
#[test]
fn part_of_expr_stmt() {
check_assist(
extract_function,
r#"
fn foo() {
$01$0 + 1;
}
"#,
r#"
fn foo() {
fun_name() + 1;
}
fn $0fun_name() -> i32 {
1
}
"#,
);
}
#[test]
fn function_expr() {
check_assist(
extract_function,
r#"
fn foo() {
$0bar(1 + 1)$0
}
"#,
r#"
fn foo() {
fun_name();
}
fn $0fun_name() {
bar(1 + 1)
}
"#,
)
}
#[test]
fn extract_from_nested() {
check_assist(
extract_function,
r#"
fn main() {
let x = true;
let tuple = match x {
true => ($02 + 2$0, true)
_ => (0, false)
};
}
"#,
r#"
fn main() {
let x = true;
let tuple = match x {
true => (fun_name(), true)
_ => (0, false)
};
}
fn $0fun_name() -> i32 {
2 + 2
}
"#,
);
}
#[test]
fn param_from_closure() {
check_assist(
extract_function,
r#"
fn main() {
let lambda = |x: u32| $0x * 2$0;
}
"#,
r#"
fn main() {
let lambda = |x: u32| fun_name(x);
}
fn $0fun_name(x: u32) -> u32 {
x * 2
}
"#,
);
}
#[test]
fn extract_return_stmt() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
$0return 2 + 2$0;
}
"#,
r#"
fn foo() -> u32 {
return fun_name();
}
fn $0fun_name() -> u32 {
2 + 2
}
"#,
);
}
#[test]
fn does_not_add_extra_whitespace() {
check_assist(
extract_function,
r#"
fn foo() -> u32 {
$0return 2 + 2$0;
}
"#,
r#"
fn foo() -> u32 {
return fun_name();
}
fn $0fun_name() -> u32 {
2 + 2
}
"#,
);
}
#[test]
fn break_stmt() {
check_assist(
extract_function,
r#"
fn main() {
let result = loop {
$0break 2 + 2$0;
};
}
"#,
r#"
fn main() {
let result = loop {
break fun_name();
};
}
fn $0fun_name() -> i32 {
2 + 2
}
"#,
);
}
#[test]
fn extract_cast() {
check_assist(
extract_function,
r#"
fn main() {
let v = $00f32 as u32$0;
}
"#,
r#"
fn main() {
let v = fun_name();
}
fn $0fun_name() -> u32 {
0f32 as u32
}
"#,
);
}
#[test]
fn return_not_applicable() {
check_assist_not_applicable(extract_function, r"fn foo() { $0return$0; } ");
}
#[test]
fn method_to_freestanding() {
check_assist(
extract_function,
r#"
struct S;
impl S {
fn foo(&self) -> i32 {
$01+1$0
}
}
"#,
r#"
struct S;
impl S {
fn foo(&self) -> i32 {
fun_name()
}
}
fn $0fun_name() -> i32 {
1+1
}
"#,
);
}
#[test]
fn method_with_reference() {
check_assist(
extract_function,
r#"
struct S { f: i32 };
impl S {
fn foo(&self) -> i32 {
$0self.f+self.f$0
}
}
"#,
r#"
struct S { f: i32 };
impl S {
fn foo(&self) -> i32 {
self.fun_name()
}
fn $0fun_name(&self) -> i32 {
self.f+self.f
}
}
"#,
);
}
#[test]
fn method_with_mut() {
check_assist(
extract_function,
r#"
struct S { f: i32 };
impl S {
fn foo(&mut self) {
$0self.f += 1;$0
}
}
"#,
r#"
struct S { f: i32 };
impl S {
fn foo(&mut self) {
self.fun_name();
}
fn $0fun_name(&mut self) {
self.f += 1;
}
}
"#,
);
}
#[test]
fn variable_defined_inside_and_used_after_no_ret() {
check_assist(
extract_function,
r#"
fn foo() {
let n = 1;
$0let k = n * n;$0
let m = k + 1;
}
"#,
r#"
fn foo() {
let n = 1;
let k = fun_name(n);
let m = k + 1;
}
fn $0fun_name(n: i32) -> i32 {
let k = n * n;
k
}
"#,
);
}
#[test]
fn variable_defined_inside_and_used_after_mutably_no_ret() {
check_assist(
extract_function,
r#"
fn foo() {
let n = 1;
$0let mut k = n * n;$0
k += 1;
}
"#,
r#"
fn foo() {
let n = 1;
let mut k = fun_name(n);
k += 1;
}
fn $0fun_name(n: i32) -> i32 {
let mut k = n * n;
k
}
"#,
);
}
#[test]
fn two_variables_defined_inside_and_used_after_no_ret() {
check_assist(
extract_function,
r#"
fn foo() {
let n = 1;
$0let k = n * n;
let m = k + 2;$0
let h = k + m;
}
"#,
r#"
fn foo() {
let n = 1;
let (k, m) = fun_name(n);
let h = k + m;
}
fn $0fun_name(n: i32) -> (i32, i32) {
let k = n * n;
let m = k + 2;
(k, m)
}
"#,
);
}
#[test]
fn multi_variables_defined_inside_and_used_after_mutably_no_ret() {
check_assist(
extract_function,
r#"
fn foo() {
let n = 1;
$0let mut k = n * n;
let mut m = k + 2;
let mut o = m + 3;
o += 1;$0
k += o;
m = 1;
}
"#,
r#"
fn foo() {
let n = 1;
let (mut k, mut m, o) = fun_name(n);
k += o;
m = 1;
}
fn $0fun_name(n: i32) -> (i32, i32, i32) {
let mut k = n * n;
let mut m = k + 2;
let mut o = m + 3;
o += 1;
(k, m, o)
}
"#,
);
}
#[test]
fn nontrivial_patterns_define_variables() {
check_assist(
extract_function,
r#"
struct Counter(i32);
fn foo() {
$0let Counter(n) = Counter(0);$0
let m = n;
}
"#,
r#"
struct Counter(i32);
fn foo() {
let n = fun_name();
let m = n;
}
fn $0fun_name() -> i32 {
let Counter(n) = Counter(0);
n
}
"#,
);
}
#[test]
fn struct_with_two_fields_pattern_define_variables() {
check_assist(
extract_function,
r#"
struct Counter { n: i32, m: i32 };
fn foo() {
$0let Counter { n, m: k } = Counter { n: 1, m: 2 };$0
let h = n + k;
}
"#,
r#"
struct Counter { n: i32, m: i32 };
fn foo() {
let (n, k) = fun_name();
let h = n + k;
}
fn $0fun_name() -> (i32, i32) {
let Counter { n, m: k } = Counter { n: 1, m: 2 };
(n, k)
}
"#,
);
}
#[test]
fn mut_var_from_outer_scope() {
check_assist(
extract_function,
r#"
fn foo() {
let mut n = 1;
$0n += 1;$0
let m = n + 1;
}
"#,
r#"
fn foo() {
let mut n = 1;
fun_name(&mut n);
let m = n + 1;
}
fn $0fun_name(n: &mut i32) {
*n += 1;
}
"#,
);
}
#[test]
fn mut_field_from_outer_scope() {
check_assist(
extract_function,
r#"
struct C { n: i32 }
fn foo() {
let mut c = C { n: 0 };
$0c.n += 1;$0
let m = c.n + 1;
}
"#,
r#"
struct C { n: i32 }
fn foo() {
let mut c = C { n: 0 };
fun_name(&mut c);
let m = c.n + 1;
}
fn $0fun_name(c: &mut C) {
c.n += 1;
}
"#,
);
}
#[test]
fn mut_nested_field_from_outer_scope() {
check_assist(
extract_function,
r#"
struct P { n: i32}
struct C { p: P }
fn foo() {
let mut c = C { p: P { n: 0 } };
let mut v = C { p: P { n: 0 } };
let u = C { p: P { n: 0 } };
$0c.p.n += u.p.n;
let r = &mut v.p.n;$0
let m = c.p.n + v.p.n + u.p.n;
}
"#,
r#"
struct P { n: i32}
struct C { p: P }
fn foo() {
let mut c = C { p: P { n: 0 } };
let mut v = C { p: P { n: 0 } };
let u = C { p: P { n: 0 } };
fun_name(&mut c, &u, &mut v);
let m = c.p.n + v.p.n + u.p.n;
}
fn $0fun_name(c: &mut C, u: &C, v: &mut C) {
c.p.n += u.p.n;
let r = &mut v.p.n;
}
"#,
);
}
#[test]
fn mut_param_many_usages_stmt() {
check_assist(
extract_function,
r#"
fn bar(k: i32) {}
trait I: Copy {
fn succ(&self) -> Self;
fn inc(&mut self) -> Self { let v = self.succ(); *self = v; v }
}
impl I for i32 {
fn succ(&self) -> Self { *self + 1 }
}
fn foo() {
let mut n = 1;
$0n += n;
bar(n);
bar(n+1);
bar(n*n);
bar(&n);
n.inc();
let v = &mut n;
*v = v.succ();
n.succ();$0
let m = n + 1;
}
"#,
r#"
fn bar(k: i32) {}
trait I: Copy {
fn succ(&self) -> Self;
fn inc(&mut self) -> Self { let v = self.succ(); *self = v; v }
}
impl I for i32 {
fn succ(&self) -> Self { *self + 1 }
}
fn foo() {
let mut n = 1;
fun_name(&mut n);
let m = n + 1;
}
fn $0fun_name(n: &mut i32) {
*n += *n;
bar(*n);
bar(*n+1);
bar(*n**n);
bar(&*n);
n.inc();
let v = n;
*v = v.succ();
n.succ();
}
"#,
);
}
#[test]
fn mut_param_many_usages_expr() {
check_assist(
extract_function,
r#"
fn bar(k: i32) {}
trait I: Copy {
fn succ(&self) -> Self;
fn inc(&mut self) -> Self { let v = self.succ(); *self = v; v }
}
impl I for i32 {
fn succ(&self) -> Self { *self + 1 }
}
fn foo() {
let mut n = 1;
$0{
n += n;
bar(n);
bar(n+1);
bar(n*n);
bar(&n);
n.inc();
let v = &mut n;
*v = v.succ();
n.succ();
}$0
let m = n + 1;
}
"#,
r#"
fn bar(k: i32) {}
trait I: Copy {
fn succ(&self) -> Self;
fn inc(&mut self) -> Self { let v = self.succ(); *self = v; v }
}
impl I for i32 {
fn succ(&self) -> Self { *self + 1 }
}
fn foo() {
let mut n = 1;
fun_name(&mut n);
let m = n + 1;
}
fn $0fun_name(n: &mut i32) {
*n += *n;
bar(*n);
bar(*n+1);
bar(*n**n);
bar(&*n);
n.inc();
let v = n;
*v = v.succ();
n.succ();
}
"#,
);
}
#[test]
fn mut_param_by_value() {
check_assist(
extract_function,
r#"
fn foo() {
let mut n = 1;
$0n += 1;$0
}
"#,
r"
fn foo() {
let mut n = 1;
fun_name(n);
}
fn $0fun_name(mut n: i32) {
n += 1;
}
",
);
}
#[test]
fn mut_param_because_of_mut_ref() {
check_assist(
extract_function,
r#"
fn foo() {
let mut n = 1;
$0let v = &mut n;
*v += 1;$0
let k = n;
}
"#,
r#"
fn foo() {
let mut n = 1;
fun_name(&mut n);
let k = n;
}
fn $0fun_name(n: &mut i32) {
let v = n;
*v += 1;
}
"#,
);
}
#[test]
fn mut_param_by_value_because_of_mut_ref() {
check_assist(
extract_function,
r"
fn foo() {
let mut n = 1;
$0let v = &mut n;
*v += 1;$0
}
",
r#"
fn foo() {
let mut n = 1;
fun_name(n);
}
fn $0fun_name(mut n: i32) {
let v = &mut n;
*v += 1;
}
"#,
);
}
#[test]
fn mut_method_call() {
check_assist(
extract_function,
r#"
trait I {
fn inc(&mut self);
}
impl I for i32 {
fn inc(&mut self) { *self += 1 }
}
fn foo() {
let mut n = 1;
$0n.inc();$0
}
"#,
r#"
trait I {
fn inc(&mut self);
}
impl I for i32 {
fn inc(&mut self) { *self += 1 }
}
fn foo() {
let mut n = 1;
fun_name(n);
}
fn $0fun_name(mut n: i32) {
n.inc();
}
"#,
);
}
#[test]
fn shared_method_call() {
check_assist(
extract_function,
r#"
trait I {
fn succ(&self);
}
impl I for i32 {
fn succ(&self) { *self + 1 }
}
fn foo() {
let mut n = 1;
$0n.succ();$0
}
"#,
r"
trait I {
fn succ(&self);
}
impl I for i32 {
fn succ(&self) { *self + 1 }
}
fn foo() {
let mut n = 1;
fun_name(n);
}
fn $0fun_name(n: i32) {
n.succ();
}
",
);
}
#[test]
fn mut_method_call_with_other_receiver() {
check_assist(
extract_function,
r#"
trait I {
fn inc(&mut self, n: i32);
}
impl I for i32 {
fn inc(&mut self, n: i32) { *self += n }
}
fn foo() {
let mut n = 1;
$0let mut m = 2;
m.inc(n);$0
}
"#,
r"
trait I {
fn inc(&mut self, n: i32);
}
impl I for i32 {
fn inc(&mut self, n: i32) { *self += n }
}
fn foo() {
let mut n = 1;
fun_name(n);
}
fn $0fun_name(n: i32) {
let mut m = 2;
m.inc(n);
}
",
);
}
#[test]
fn non_copy_without_usages_after() {
check_assist(
extract_function,
r#"
struct Counter(i32);
fn foo() {
let c = Counter(0);
$0let n = c.0;$0
}
"#,
r"
struct Counter(i32);
fn foo() {
let c = Counter(0);
fun_name(c);
}
fn $0fun_name(c: Counter) {
let n = c.0;
}
",
);
}
#[test]
fn non_copy_used_after() {
check_assist(
extract_function,
r"
struct Counter(i32);
fn foo() {
let c = Counter(0);
$0let n = c.0;$0
let m = c.0;
}
",
r#"
struct Counter(i32);
fn foo() {
let c = Counter(0);
fun_name(&c);
let m = c.0;
}
fn $0fun_name(c: &Counter) {
let n = c.0;
}
"#,
);
}
#[test]
fn copy_used_after() {
check_assist(
extract_function,
r#"
//- minicore: copy
fn foo() {
let n = 0;
$0let m = n;$0
let k = n;
}
"#,
r#"
fn foo() {
let n = 0;
fun_name(n);
let k = n;
}
fn $0fun_name(n: i32) {
let m = n;
}
"#,
)
}
#[test]
fn copy_custom_used_after() {
check_assist(
extract_function,
r#"
//- minicore: copy, derive
#[derive(Clone, Copy)]
struct Counter(i32);
fn foo() {
let c = Counter(0);
$0let n = c.0;$0
let m = c.0;
}
"#,
r#"
#[derive(Clone, Copy)]
struct Counter(i32);
fn foo() {
let c = Counter(0);
fun_name(c);
let m = c.0;
}
fn $0fun_name(c: Counter) {
let n = c.0;
}
"#,
);
}
#[test]
fn indented_stmts() {
check_assist(
extract_function,
r#"
fn foo() {
if true {
loop {
$0let n = 1;
let m = 2;$0
}
}
}
"#,
r#"
fn foo() {
if true {
loop {
fun_name();
}
}
}
fn $0fun_name() {
let n = 1;
let m = 2;
}
"#,
);
}
#[test]
fn indented_stmts_inside_mod() {
check_assist(
extract_function,
r#"
mod bar {
fn foo() {
if true {
loop {
$0let n = 1;
let m = 2;$0
}
}
}
}
"#,
r#"
mod bar {
fn foo() {
if true {
loop {
fun_name();
}
}
}
fn $0fun_name() {
let n = 1;
let m = 2;
}
}
"#,
);
}
#[test]
fn break_loop() {
check_assist(
extract_function,
r#"
//- minicore: option
fn foo() {
loop {
let n = 1;
$0let m = n + 1;
break;
let k = 2;$0
let h = 1 + k;
}
}
"#,
r#"
fn foo() {
loop {
let n = 1;
let k = match fun_name(n) {
Some(value) => value,
None => break,
};
let h = 1 + k;
}
}
fn $0fun_name(n: i32) -> Option<i32> {
let m = n + 1;
return None;
let k = 2;
Some(k)
}
"#,
);
}
#[test]
fn return_to_parent() {
check_assist(
extract_function,
r#"
//- minicore: copy, result
fn foo() -> i64 {
let n = 1;
$0let m = n + 1;
return 1;
let k = 2;$0
(n + k) as i64
}
"#,
r#"
fn foo() -> i64 {
let n = 1;
let k = match fun_name(n) {
Ok(value) => value,
Err(value) => return value,
};
(n + k) as i64
}
fn $0fun_name(n: i32) -> Result<i32, i64> {
let m = n + 1;
return Err(1);
let k = 2;
Ok(k)
}
"#,
);
}
#[test]
fn break_and_continue() {
cov_mark::check!(external_control_flow_break_and_continue);
check_assist_not_applicable(
extract_function,
r#"
fn foo() {
loop {
let n = 1;
$0let m = n + 1;
break;
let k = 2;
continue;
let k = k + 1;$0
let r = n + k;
}
}
"#,
);
}
#[test]
fn return_and_break() {
cov_mark::check!(external_control_flow_return_and_bc);
check_assist_not_applicable(
extract_function,
r#"
fn foo() {
loop {
let n = 1;
$0let m = n + 1;
break;
let k = 2;
return;
let k = k + 1;$0
let r = n + k;
}
}
"#,
);
}
#[test]
fn break_loop_with_if() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let mut n = 1;
$0let m = n + 1;
break;
n += m;$0
let h = 1 + n;
}
}
"#,
r#"
fn foo() {
loop {
let mut n = 1;
if fun_name(&mut n) {
break;
}
let h = 1 + n;
}
}
fn $0fun_name(n: &mut i32) -> bool {
let m = *n + 1;
return true;
*n += m;
false
}
"#,
);
}
#[test]
fn break_loop_nested() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let mut n = 1;
$0let m = n + 1;
if m == 42 {
break;
}$0
let h = 1;
}
}
"#,
r#"
fn foo() {
loop {
let mut n = 1;
if fun_name(n) {
break;
}
let h = 1;
}
}
fn $0fun_name(n: i32) -> bool {
let m = n + 1;
if m == 42 {
return true;
}
false
}
"#,
);
}
#[test]
fn return_from_nested_loop() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let n = 1;$0
let k = 1;
loop {
return;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
fn foo() {
loop {
let n = 1;
let m = match fun_name() {
Some(value) => value,
None => return,
};
let h = 1 + m;
}
}
fn $0fun_name() -> Option<i32> {
let k = 1;
loop {
return None;
}
let m = k + 1;
Some(m)
}
"#,
);
}
#[test]
fn break_from_nested_loop() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let n = 1;
$0let k = 1;
loop {
break;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
fn foo() {
loop {
let n = 1;
let m = fun_name();
let h = 1 + m;
}
}
fn $0fun_name() -> i32 {
let k = 1;
loop {
break;
}
let m = k + 1;
m
}
"#,
);
}
#[test]
fn break_from_nested_and_outer_loops() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let n = 1;
$0let k = 1;
loop {
break;
}
if k == 42 {
break;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
fn foo() {
loop {
let n = 1;
let m = match fun_name() {
Some(value) => value,
None => break,
};
let h = 1 + m;
}
}
fn $0fun_name() -> Option<i32> {
let k = 1;
loop {
break;
}
if k == 42 {
return None;
}
let m = k + 1;
Some(m)
}
"#,
);
}
#[test]
fn return_from_nested_fn() {
check_assist(
extract_function,
r#"
fn foo() {
loop {
let n = 1;
$0let k = 1;
fn test() {
return;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
fn foo() {
loop {
let n = 1;
let m = fun_name();
let h = 1 + m;
}
}
fn $0fun_name() -> i32 {
let k = 1;
fn test() {
return;
}
let m = k + 1;
m
}
"#,
);
}
#[test]
fn break_with_value() {
check_assist(
extract_function,
r#"
fn foo() -> i32 {
loop {
let n = 1;
$0let k = 1;
if k == 42 {
break 3;
}
let m = k + 1;$0
let h = 1;
}
}
"#,
r#"
fn foo() -> i32 {
loop {
let n = 1;
if let Some(value) = fun_name() {
break value;
}
let h = 1;
}
}
fn $0fun_name() -> Option<i32> {
let k = 1;
if k == 42 {
return Some(3);
}
let m = k + 1;
None
}
"#,
);
}
#[test]
fn break_with_value_and_return() {
check_assist(
extract_function,
r#"
fn foo() -> i64 {
loop {
let n = 1;$0
let k = 1;
if k == 42 {
break 3;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
fn foo() -> i64 {
loop {
let n = 1;
let m = match fun_name() {
Ok(value) => value,
Err(value) => break value,
};
let h = 1 + m;
}
}
fn $0fun_name() -> Result<i32, i64> {
let k = 1;
if k == 42 {
return Err(3);
}
let m = k + 1;
Ok(m)
}
"#,
);
}
#[test]
fn try_option() {
check_assist(
extract_function,
r#"
//- minicore: option
fn bar() -> Option<i32> { None }
fn foo() -> Option<()> {
let n = bar()?;
$0let k = foo()?;
let m = k + 1;$0
let h = 1 + m;
Some(())
}
"#,
r#"
fn bar() -> Option<i32> { None }
fn foo() -> Option<()> {
let n = bar()?;
let m = fun_name()?;
let h = 1 + m;
Some(())
}
fn $0fun_name() -> Option<i32> {
let k = foo()?;
let m = k + 1;
Some(m)
}
"#,
);
}
#[test]
fn try_option_unit() {
check_assist(
extract_function,
r#"
//- minicore: option
fn foo() -> Option<()> {
let n = 1;
$0let k = foo()?;
let m = k + 1;$0
let h = 1 + n;
Some(())
}
"#,
r#"
fn foo() -> Option<()> {
let n = 1;
fun_name()?;
let h = 1 + n;
Some(())
}
fn $0fun_name() -> Option<()> {
let k = foo()?;
let m = k + 1;
Some(())
}
"#,
);
}
#[test]
fn try_result() {
check_assist(
extract_function,
r#"
//- minicore: result
fn foo() -> Result<(), i64> {
let n = 1;
$0let k = foo()?;
let m = k + 1;$0
let h = 1 + m;
Ok(())
}
"#,
r#"
fn foo() -> Result<(), i64> {
let n = 1;
let m = fun_name()?;
let h = 1 + m;
Ok(())
}
fn $0fun_name() -> Result<i32, i64> {
let k = foo()?;
let m = k + 1;
Ok(m)
}
"#,
);
}
#[test]
fn try_option_with_return() {
check_assist(
extract_function,
r#"
//- minicore: option
fn foo() -> Option<()> {
let n = 1;
$0let k = foo()?;
if k == 42 {
return None;
}
let m = k + 1;$0
let h = 1 + m;
Some(())
}
"#,
r#"
fn foo() -> Option<()> {
let n = 1;
let m = fun_name()?;
let h = 1 + m;
Some(())
}
fn $0fun_name() -> Option<i32> {
let k = foo()?;
if k == 42 {
return None;
}
let m = k + 1;
Some(m)
}
"#,
);
}
#[test]
fn try_result_with_return() {
check_assist(
extract_function,
r#"
//- minicore: result
fn foo() -> Result<(), i64> {
let n = 1;
$0let k = foo()?;
if k == 42 {
return Err(1);
}
let m = k + 1;$0
let h = 1 + m;
Ok(())
}
"#,
r#"
fn foo() -> Result<(), i64> {
let n = 1;
let m = fun_name()?;
let h = 1 + m;
Ok(())
}
fn $0fun_name() -> Result<i32, i64> {
let k = foo()?;
if k == 42 {
return Err(1);
}
let m = k + 1;
Ok(m)
}
"#,
);
}
#[test]
fn try_and_break() {
cov_mark::check!(external_control_flow_try_and_bc);
check_assist_not_applicable(
extract_function,
r#"
//- minicore: option
fn foo() -> Option<()> {
loop {
let n = Some(1);
$0let m = n? + 1;
break;
let k = 2;
let k = k + 1;$0
let r = n + k;
}
Some(())
}
"#,
);
}
#[test]
fn try_and_return_ok() {
check_assist(
extract_function,
r#"
//- minicore: result
fn foo() -> Result<(), i64> {
let n = 1;
$0let k = foo()?;
if k == 42 {
return Ok(1);
}
let m = k + 1;$0
let h = 1 + m;
Ok(())
}
"#,
r#"
fn foo() -> Result<(), i64> {
let n = 1;
let m = fun_name()?;
let h = 1 + m;
Ok(())
}
fn $0fun_name() -> Result<i32, i64> {
let k = foo()?;
if k == 42 {
return Ok(1);
}
let m = k + 1;
Ok(m)
}
"#,
);
}
#[test]
fn param_usage_in_macro() {
check_assist(
extract_function,
r#"
macro_rules! m {
($val:expr) => { $val };
}
fn foo() {
let n = 1;
$0let k = n * m!(n);$0
let m = k + 1;
}
"#,
r#"
macro_rules! m {
($val:expr) => { $val };
}
fn foo() {
let n = 1;
let k = fun_name(n);
let m = k + 1;
}
fn $0fun_name(n: i32) -> i32 {
let k = n * m!(n);
k
}
"#,
);
}
#[test]
fn extract_with_await() {
check_assist(
extract_function,
r#"
fn main() {
$0some_function().await;$0
}
async fn some_function() {
}
"#,
r#"
fn main() {
fun_name().await;
}
async fn $0fun_name() {
some_function().await;
}
async fn some_function() {
}
"#,
);
}
#[test]
fn extract_with_await_and_result_not_producing_match_expr() {
check_assist(
extract_function,
r#"
async fn foo() -> Result<(), ()> {
$0async {}.await;
Err(())?$0
}
"#,
r#"
async fn foo() -> Result<(), ()> {
fun_name().await?
}
async fn $0fun_name() -> _ {
async {}.await;
Err(())?
}
"#,
);
}
#[test]
fn extract_with_await_and_result_producing_match_expr() {
check_assist(
extract_function,
r#"
async fn foo() -> i32 {
loop {
let n = 1;$0
let k = async { 1 }.await;
if k == 42 {
break 3;
}
let m = k + 1;$0
let h = 1 + m;
}
}
"#,
r#"
async fn foo() -> i32 {
loop {
let n = 1;
let m = match fun_name().await {
Ok(value) => value,
Err(value) => break value,
};
let h = 1 + m;
}
}
async fn $0fun_name() -> Result<i32, i32> {
let k = async { 1 }.await;
if k == 42 {
return Err(3);
}
let m = k + 1;
Ok(m)
}
"#,
);
}
#[test]
fn extract_with_await_in_args() {
check_assist(
extract_function,
r#"
fn main() {
$0function_call("a", some_function().await);$0
}
async fn some_function() {
}
"#,
r#"
fn main() {
fun_name().await;
}
async fn $0fun_name() {
function_call("a", some_function().await);
}
async fn some_function() {
}
"#,
);
}
#[test]
fn extract_does_not_extract_standalone_blocks() {
check_assist_not_applicable(
extract_function,
r#"
fn main() $0{}$0
"#,
);
}
#[test]
fn extract_adds_comma_for_match_arm() {
check_assist(
extract_function,
r#"
fn main() {
match 6 {
100 => $0{ 100 }$0
_ => 0,
}
}
"#,
r#"
fn main() {
match 6 {
100 => fun_name(),
_ => 0,
}
}
fn $0fun_name() -> i32 {
100
}
"#,
);
check_assist(
extract_function,
r#"
fn main() {
match 6 {
100 => $0{ 100 }$0,
_ => 0,
}
}
"#,
r#"
fn main() {
match 6 {
100 => fun_name(),
_ => 0,
}
}
fn $0fun_name() -> i32 {
100
}
"#,
);
}
#[test]
fn extract_does_not_tear_comments_apart() {
check_assist(
extract_function,
r#"
fn foo() {
/*$0*/
foo();
foo();
/*$0*/
}
"#,
r#"
fn foo() {
/**/
fun_name();
/**/
}
fn $0fun_name() {
foo();
foo();
}
"#,
);
}
#[test]
fn extract_does_not_wrap_res_in_res() {
check_assist(
extract_function,
r#"
//- minicore: result
fn foo() -> Result<(), i64> {
$0Result::<i32, i64>::Ok(0)?;
Ok(())$0
}
"#,
r#"
fn foo() -> Result<(), i64> {
fun_name()?
}
fn $0fun_name() -> Result<(), i64> {
Result::<i32, i64>::Ok(0)?;
Ok(())
}
"#,
);
}
#[test]
fn extract_knows_const() {
check_assist(
extract_function,
r#"
const fn foo() {
$0()$0
}
"#,
r#"
const fn foo() {
fun_name();
}
const fn $0fun_name() {
()
}
"#,
);
check_assist(
extract_function,
r#"
const FOO: () = {
$0()$0
};
"#,
r#"
const FOO: () = {
fun_name();
};
const fn $0fun_name() {
()
}
"#,
);
}
#[test]
fn extract_does_not_move_outer_loop_vars() {
check_assist(
extract_function,
r#"
fn foo() {
let mut x = 5;
for _ in 0..10 {
$0x += 1;$0
}
}
"#,
r#"
fn foo() {
let mut x = 5;
for _ in 0..10 {
fun_name(&mut x);
}
}
fn $0fun_name(x: &mut i32) {
*x += 1;
}
"#,
);
check_assist(
extract_function,
r#"
fn foo() {
for _ in 0..10 {
let mut x = 5;
$0x += 1;$0
}
}
"#,
r#"
fn foo() {
for _ in 0..10 {
let mut x = 5;
fun_name(x);
}
}
fn $0fun_name(mut x: i32) {
x += 1;
}
"#,
);
check_assist(
extract_function,
r#"
fn foo() {
loop {
let mut x = 5;
for _ in 0..10 {
$0x += 1;$0
}
}
}
"#,
r#"
fn foo() {
loop {
let mut x = 5;
for _ in 0..10 {
fun_name(&mut x);
}
}
}
fn $0fun_name(x: &mut i32) {
*x += 1;
}
"#,
);
}
// regression test for #9822
#[test]
fn extract_mut_ref_param_has_no_mut_binding_in_loop() {
check_assist(
extract_function,
r#"
struct Foo;
impl Foo {
fn foo(&mut self) {}
}
fn foo() {
let mut x = Foo;
while false {
let y = &mut x;
$0y.foo();$0
}
let z = x;
}
"#,
r#"
struct Foo;
impl Foo {
fn foo(&mut self) {}
}
fn foo() {
let mut x = Foo;
while false {
let y = &mut x;
fun_name(y);
}
let z = x;
}
fn $0fun_name(y: &mut Foo) {
y.foo();
}
"#,
);
}
#[test]
fn extract_with_macro_arg() {
check_assist(
extract_function,
r#"
macro_rules! m {
($val:expr) => { $val };
}
fn main() {
let bar = "bar";
$0m!(bar);$0
}
"#,
r#"
macro_rules! m {
($val:expr) => { $val };
}
fn main() {
let bar = "bar";
fun_name(bar);
}
fn $0fun_name(bar: &str) {
m!(bar);
}
"#,
);
}
#[test]
fn unresolveable_types_default_to_placeholder() {
check_assist(
extract_function,
r#"
fn foo() {
let a = __unresolved;
let _ = $0{a}$0;
}
"#,
r#"
fn foo() {
let a = __unresolved;
let _ = fun_name(a);
}
fn $0fun_name(a: _) -> _ {
a
}
"#,
);
}
}