1 //! A module with ide helpers for high-level ide features.
6 pub mod generated_lints;
8 use std::collections::VecDeque;
12 use hir::{Crate, Enum, ItemInNs, MacroDef, Module, ModuleDef, Name, ScopeDef, Semantics, Trait};
14 ast::{self, make, LoopBodyOwner},
15 AstNode, Direction, SyntaxElement, SyntaxKind, SyntaxToken, TokenAtOffset, WalkEvent, T,
18 use crate::RootDatabase;
20 pub fn item_name(db: &RootDatabase, item: ItemInNs) -> Option<Name> {
22 ItemInNs::Types(module_def_id) => ModuleDef::from(module_def_id).name(db),
23 ItemInNs::Values(module_def_id) => ModuleDef::from(module_def_id).name(db),
24 ItemInNs::Macros(macro_def_id) => MacroDef::from(macro_def_id).name(db),
28 /// Resolves the path at the cursor token as a derive macro if it inside a token tree of a derive attribute.
29 pub fn try_resolve_derive_input_at(
30 sema: &Semantics<RootDatabase>,
31 derive_attr: &ast::Attr,
33 ) -> Option<MacroDef> {
34 use itertools::Itertools;
35 if cursor.kind() != T![ident] {
38 let tt = match derive_attr.as_simple_call() {
40 if name == "derive" && tt.syntax().text_range().contains_range(cursor.text_range()) =>
46 let tokens: Vec<_> = cursor
47 .siblings_with_tokens(Direction::Prev)
48 .flat_map(SyntaxElement::into_token)
49 .take_while(|tok| tok.kind() != T!['('] && tok.kind() != T![,])
51 let path = ast::Path::parse(&tokens.into_iter().rev().join("")).ok()?;
52 match sema.scope(tt.syntax()).speculative_resolve(&path) {
53 Some(hir::PathResolution::Macro(makro)) if makro.kind() == hir::MacroKind::Derive => {
60 /// Picks the token with the highest rank returned by the passed in function.
61 pub fn pick_best_token(
62 tokens: TokenAtOffset<SyntaxToken>,
63 f: impl Fn(SyntaxKind) -> usize,
64 ) -> Option<SyntaxToken> {
65 tokens.max_by_key(move |t| f(t.kind()))
68 /// Converts the mod path struct into its ast representation.
69 pub fn mod_path_to_ast(path: &hir::ModPath) -> ast::Path {
70 let _p = profile::span("mod_path_to_ast");
72 let mut segments = Vec::new();
73 let mut is_abs = false;
75 hir::PathKind::Plain => {}
76 hir::PathKind::Super(0) => segments.push(make::path_segment_self()),
77 hir::PathKind::Super(n) => segments.extend((0..n).map(|_| make::path_segment_super())),
78 hir::PathKind::DollarCrate(_) | hir::PathKind::Crate => {
79 segments.push(make::path_segment_crate())
81 hir::PathKind::Abs => is_abs = true,
87 .map(|segment| make::path_segment(make::name_ref(&segment.to_string()))),
89 make::path_from_segments(segments, is_abs)
92 /// Iterates all `ModuleDef`s and `Impl` blocks of the given file.
93 pub fn visit_file_defs(
94 sema: &Semantics<RootDatabase>,
96 cb: &mut dyn FnMut(Either<hir::ModuleDef, hir::Impl>),
99 let module = match sema.to_module_def(file_id) {
103 let mut defs: VecDeque<_> = module.declarations(db).into();
104 while let Some(def) = defs.pop_front() {
105 if let ModuleDef::Module(submodule) = def {
106 if let hir::ModuleSource::Module(_) = submodule.definition_source(db).value {
107 defs.extend(submodule.declarations(db));
108 submodule.impl_defs(db).into_iter().for_each(|impl_| cb(Either::Right(impl_)));
111 cb(Either::Left(def));
113 module.impl_defs(db).into_iter().for_each(|impl_| cb(Either::Right(impl_)));
116 /// Helps with finding well-know things inside the standard library. This is
117 /// somewhat similar to the known paths infra inside hir, but it different; We
118 /// want to make sure that IDE specific paths don't become interesting inside
119 /// the compiler itself as well.
121 /// Note that, by default, rust-analyzer tests **do not** include core or std
122 /// libraries. If you are writing tests for functionality using [`FamousDefs`],
123 /// you'd want to include minicore (see `test_utils::MiniCore`) declaration at
124 /// the start of your tests:
127 /// //- minicore: iterator, ord, derive
129 pub struct FamousDefs<'a, 'b>(pub &'a Semantics<'b, RootDatabase>, pub Option<Crate>);
131 #[allow(non_snake_case)]
132 impl FamousDefs<'_, '_> {
133 pub fn std(&self) -> Option<Crate> {
134 self.find_crate("std")
137 pub fn core(&self) -> Option<Crate> {
138 self.find_crate("core")
141 pub fn core_cmp_Ord(&self) -> Option<Trait> {
142 self.find_trait("core:cmp:Ord")
145 pub fn core_convert_From(&self) -> Option<Trait> {
146 self.find_trait("core:convert:From")
149 pub fn core_convert_Into(&self) -> Option<Trait> {
150 self.find_trait("core:convert:Into")
153 pub fn core_option_Option(&self) -> Option<Enum> {
154 self.find_enum("core:option:Option")
157 pub fn core_result_Result(&self) -> Option<Enum> {
158 self.find_enum("core:result:Result")
161 pub fn core_default_Default(&self) -> Option<Trait> {
162 self.find_trait("core:default:Default")
165 pub fn core_iter_Iterator(&self) -> Option<Trait> {
166 self.find_trait("core:iter:traits:iterator:Iterator")
169 pub fn core_iter_IntoIterator(&self) -> Option<Trait> {
170 self.find_trait("core:iter:traits:collect:IntoIterator")
173 pub fn core_iter(&self) -> Option<Module> {
174 self.find_module("core:iter")
177 pub fn core_ops_Deref(&self) -> Option<Trait> {
178 self.find_trait("core:ops:Deref")
181 fn find_trait(&self, path: &str) -> Option<Trait> {
182 match self.find_def(path)? {
183 hir::ScopeDef::ModuleDef(hir::ModuleDef::Trait(it)) => Some(it),
188 fn find_enum(&self, path: &str) -> Option<Enum> {
189 match self.find_def(path)? {
190 hir::ScopeDef::ModuleDef(hir::ModuleDef::Adt(hir::Adt::Enum(it))) => Some(it),
195 fn find_module(&self, path: &str) -> Option<Module> {
196 match self.find_def(path)? {
197 hir::ScopeDef::ModuleDef(hir::ModuleDef::Module(it)) => Some(it),
202 fn find_crate(&self, name: &str) -> Option<Crate> {
206 krate.dependencies(db).into_iter().find(|dep| dep.name.to_string() == name)?.krate;
210 fn find_def(&self, path: &str) -> Option<ScopeDef> {
212 let mut path = path.split(':');
213 let trait_ = path.next_back()?;
214 let std_crate = path.next()?;
215 let std_crate = self.find_crate(std_crate)?;
216 let mut module = std_crate.root_module(db);
217 for segment in path {
218 module = module.children(db).find_map(|child| {
219 let name = child.name(db)?;
220 if name.to_string() == segment {
228 module.scope(db, None).into_iter().find(|(name, _def)| name.to_string() == trait_)?.1;
233 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
234 pub struct SnippetCap {
239 pub const fn new(allow_snippets: bool) -> Option<SnippetCap> {
241 Some(SnippetCap { _private: () })
248 /// Calls `cb` on each expression inside `expr` that is at "tail position".
249 /// Does not walk into `break` or `return` expressions.
250 /// Note that modifying the tree while iterating it will cause undefined iteration which might
251 /// potentially results in an out of bounds panic.
252 pub fn for_each_tail_expr(expr: &ast::Expr, cb: &mut dyn FnMut(&ast::Expr)) {
254 ast::Expr::BlockExpr(b) => {
255 if let Some(e) = b.tail_expr() {
256 for_each_tail_expr(&e, cb);
259 ast::Expr::EffectExpr(e) => match e.effect() {
260 ast::Effect::Label(label) => {
261 for_each_break_expr(Some(label), e.block_expr(), &mut |b| {
262 cb(&ast::Expr::BreakExpr(b))
264 if let Some(b) = e.block_expr() {
265 for_each_tail_expr(&ast::Expr::BlockExpr(b), cb);
268 ast::Effect::Unsafe(_) => {
269 if let Some(e) = e.block_expr().and_then(|b| b.tail_expr()) {
270 for_each_tail_expr(&e, cb);
273 ast::Effect::Async(_) | ast::Effect::Try(_) | ast::Effect::Const(_) => cb(expr),
275 ast::Expr::IfExpr(if_) => {
276 let mut if_ = if_.clone();
278 if let Some(block) = if_.then_branch() {
279 for_each_tail_expr(&ast::Expr::BlockExpr(block), cb);
281 match if_.else_branch() {
282 Some(ast::ElseBranch::IfExpr(it)) => if_ = it,
283 Some(ast::ElseBranch::Block(block)) => {
284 for_each_tail_expr(&ast::Expr::BlockExpr(block), cb);
291 ast::Expr::LoopExpr(l) => {
292 for_each_break_expr(l.label(), l.loop_body(), &mut |b| cb(&ast::Expr::BreakExpr(b)))
294 ast::Expr::MatchExpr(m) => {
295 if let Some(arms) = m.match_arm_list() {
296 arms.arms().filter_map(|arm| arm.expr()).for_each(|e| for_each_tail_expr(&e, cb));
299 ast::Expr::ArrayExpr(_)
300 | ast::Expr::AwaitExpr(_)
301 | ast::Expr::BinExpr(_)
302 | ast::Expr::BoxExpr(_)
303 | ast::Expr::BreakExpr(_)
304 | ast::Expr::CallExpr(_)
305 | ast::Expr::CastExpr(_)
306 | ast::Expr::ClosureExpr(_)
307 | ast::Expr::ContinueExpr(_)
308 | ast::Expr::FieldExpr(_)
309 | ast::Expr::ForExpr(_)
310 | ast::Expr::IndexExpr(_)
311 | ast::Expr::Literal(_)
312 | ast::Expr::MacroCall(_)
313 | ast::Expr::MacroStmts(_)
314 | ast::Expr::MethodCallExpr(_)
315 | ast::Expr::ParenExpr(_)
316 | ast::Expr::PathExpr(_)
317 | ast::Expr::PrefixExpr(_)
318 | ast::Expr::RangeExpr(_)
319 | ast::Expr::RecordExpr(_)
320 | ast::Expr::RefExpr(_)
321 | ast::Expr::ReturnExpr(_)
322 | ast::Expr::TryExpr(_)
323 | ast::Expr::TupleExpr(_)
324 | ast::Expr::WhileExpr(_)
325 | ast::Expr::YieldExpr(_) => cb(expr),
329 /// Calls `cb` on each break expr inside of `body` that is applicable for the given label.
330 pub fn for_each_break_expr(
331 label: Option<ast::Label>,
332 body: Option<ast::BlockExpr>,
333 cb: &mut dyn FnMut(ast::BreakExpr),
335 let label = label.and_then(|lbl| lbl.lifetime());
337 if let Some(b) = body {
338 let preorder = &mut b.syntax().preorder();
339 let ev_as_expr = |ev| match ev {
340 WalkEvent::Enter(it) => Some(WalkEvent::Enter(ast::Expr::cast(it)?)),
341 WalkEvent::Leave(it) => Some(WalkEvent::Leave(ast::Expr::cast(it)?)),
343 let eq_label = |lt: Option<ast::Lifetime>| {
344 lt.zip(label.as_ref()).map_or(false, |(lt, lbl)| lt.text() == lbl.text())
346 while let Some(node) = preorder.find_map(ev_as_expr) {
348 WalkEvent::Enter(expr) => match expr {
349 ast::Expr::LoopExpr(_) | ast::Expr::WhileExpr(_) | ast::Expr::ForExpr(_) => {
352 ast::Expr::EffectExpr(e) if e.label().is_some() => depth += 1,
353 ast::Expr::BreakExpr(b)
354 if (depth == 0 && b.lifetime().is_none()) || eq_label(b.lifetime()) =>
360 WalkEvent::Leave(expr) => match expr {
361 ast::Expr::LoopExpr(_) | ast::Expr::WhileExpr(_) | ast::Expr::ForExpr(_) => {
364 ast::Expr::EffectExpr(e) if e.label().is_some() => depth -= 1,