1 //! A module with ide helpers for high-level ide features.
2 pub mod famous_defs;
3 pub mod generated_lints;
4 pub mod import_assets;
5 pub mod insert_use;
6 pub mod merge_imports;
7 pub mod node_ext;
8 pub mod rust_doc;
9
10 use std::{collections::VecDeque, iter};
11
12 use base_db::FileId;
13 use hir::{ItemInNs, MacroDef, ModuleDef, Name, PathResolution, Semantics};
14 use itertools::Itertools;
15 use syntax::{
16 ast::{self, make, HasLoopBody, Ident},
17 AstNode, AstToken, Direction, SyntaxElement, SyntaxKind, SyntaxToken, TokenAtOffset, WalkEvent,
18 T,
19 };
20
21 use crate::{defs::Definition, RootDatabase};
22
23 pub use self::famous_defs::FamousDefs;
24
item_name(db: &RootDatabase, item: ItemInNs) -> Option<Name>25 pub fn item_name(db: &RootDatabase, item: ItemInNs) -> Option<Name> {
26 match item {
27 ItemInNs::Types(module_def_id) => ModuleDef::from(module_def_id).name(db),
28 ItemInNs::Values(module_def_id) => ModuleDef::from(module_def_id).name(db),
29 ItemInNs::Macros(macro_def_id) => MacroDef::from(macro_def_id).name(db),
30 }
31 }
32
33 /// Parses and returns the derive path at the cursor position in the given attribute, if it is a derive.
34 /// This special case is required because the derive macro is a compiler builtin that discards the input derives.
35 ///
36 /// The returned path is synthesized from TokenTree tokens and as such cannot be used with the [`Semantics`].
get_path_in_derive_attr( sema: &hir::Semantics<RootDatabase>, attr: &ast::Attr, cursor: &Ident, ) -> Option<ast::Path>37 pub fn get_path_in_derive_attr(
38 sema: &hir::Semantics<RootDatabase>,
39 attr: &ast::Attr,
40 cursor: &Ident,
41 ) -> Option<ast::Path> {
42 let cursor = cursor.syntax();
43 let path = attr.path()?;
44 let tt = attr.token_tree()?;
45 if !tt.syntax().text_range().contains_range(cursor.text_range()) {
46 return None;
47 }
48 let scope = sema.scope(attr.syntax());
49 let resolved_attr = sema.resolve_path(&path)?;
50 let derive = FamousDefs(sema, scope.krate()).core_macros_builtin_derive()?;
51 if PathResolution::Macro(derive) != resolved_attr {
52 return None;
53 }
54
55 let first = cursor
56 .siblings_with_tokens(Direction::Prev)
57 .filter_map(SyntaxElement::into_token)
58 .take_while(|tok| tok.kind() != T!['('] && tok.kind() != T![,])
59 .last()?;
60 let path_tokens = first
61 .siblings_with_tokens(Direction::Next)
62 .filter_map(SyntaxElement::into_token)
63 .take_while(|tok| tok != cursor);
64
65 ast::Path::parse(&path_tokens.chain(iter::once(cursor.clone())).join("")).ok()
66 }
67
68 /// Parses and resolves the path at the cursor position in the given attribute, if it is a derive.
69 /// This special case is required because the derive macro is a compiler builtin that discards the input derives.
try_resolve_derive_input( sema: &hir::Semantics<RootDatabase>, attr: &ast::Attr, cursor: &Ident, ) -> Option<PathResolution>70 pub fn try_resolve_derive_input(
71 sema: &hir::Semantics<RootDatabase>,
72 attr: &ast::Attr,
73 cursor: &Ident,
74 ) -> Option<PathResolution> {
75 let path = get_path_in_derive_attr(sema, attr, cursor)?;
76 let scope = sema.scope(attr.syntax());
77 // FIXME: This double resolve shouldn't be necessary
78 // It's only here so we prefer macros over other namespaces
79 match scope.speculative_resolve_as_mac(&path) {
80 Some(mac) if mac.kind() == hir::MacroKind::Derive => Some(PathResolution::Macro(mac)),
81 Some(_) => return None,
82 None => scope
83 .speculative_resolve(&path)
84 .filter(|res| matches!(res, PathResolution::Def(ModuleDef::Module(_)))),
85 }
86 }
87
88 /// Picks the token with the highest rank returned by the passed in function.
pick_best_token( tokens: TokenAtOffset<SyntaxToken>, f: impl Fn(SyntaxKind) -> usize, ) -> Option<SyntaxToken>89 pub fn pick_best_token(
90 tokens: TokenAtOffset<SyntaxToken>,
91 f: impl Fn(SyntaxKind) -> usize,
92 ) -> Option<SyntaxToken> {
93 tokens.max_by_key(move |t| f(t.kind()))
94 }
95
96 /// Converts the mod path struct into its ast representation.
mod_path_to_ast(path: &hir::ModPath) -> ast::Path97 pub fn mod_path_to_ast(path: &hir::ModPath) -> ast::Path {
98 let _p = profile::span("mod_path_to_ast");
99
100 let mut segments = Vec::new();
101 let mut is_abs = false;
102 match path.kind {
103 hir::PathKind::Plain => {}
104 hir::PathKind::Super(0) => segments.push(make::path_segment_self()),
105 hir::PathKind::Super(n) => segments.extend((0..n).map(|_| make::path_segment_super())),
106 hir::PathKind::DollarCrate(_) | hir::PathKind::Crate => {
107 segments.push(make::path_segment_crate())
108 }
109 hir::PathKind::Abs => is_abs = true,
110 }
111
112 segments.extend(
113 path.segments()
114 .iter()
115 .map(|segment| make::path_segment(make::name_ref(&segment.to_smol_str()))),
116 );
117 make::path_from_segments(segments, is_abs)
118 }
119
120 /// Iterates all `ModuleDef`s and `Impl` blocks of the given file.
visit_file_defs( sema: &Semantics<RootDatabase>, file_id: FileId, cb: &mut dyn FnMut(Definition), )121 pub fn visit_file_defs(
122 sema: &Semantics<RootDatabase>,
123 file_id: FileId,
124 cb: &mut dyn FnMut(Definition),
125 ) {
126 let db = sema.db;
127 let module = match sema.to_module_def(file_id) {
128 Some(it) => it,
129 None => return,
130 };
131 let mut defs: VecDeque<_> = module.declarations(db).into();
132 while let Some(def) = defs.pop_front() {
133 if let ModuleDef::Module(submodule) = def {
134 if let hir::ModuleSource::Module(_) = submodule.definition_source(db).value {
135 defs.extend(submodule.declarations(db));
136 submodule.impl_defs(db).into_iter().for_each(|impl_| cb(impl_.into()));
137 }
138 }
139 cb(def.into());
140 }
141 module.impl_defs(db).into_iter().for_each(|impl_| cb(impl_.into()));
142 }
143
144 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
145 pub struct SnippetCap {
146 _private: (),
147 }
148
149 impl SnippetCap {
new(allow_snippets: bool) -> Option<SnippetCap>150 pub const fn new(allow_snippets: bool) -> Option<SnippetCap> {
151 if allow_snippets {
152 Some(SnippetCap { _private: () })
153 } else {
154 None
155 }
156 }
157 }
158
159 /// Calls `cb` on each expression inside `expr` that is at "tail position".
160 /// Does not walk into `break` or `return` expressions.
161 /// Note that modifying the tree while iterating it will cause undefined iteration which might
162 /// potentially results in an out of bounds panic.
for_each_tail_expr(expr: &ast::Expr, cb: &mut dyn FnMut(&ast::Expr))163 pub fn for_each_tail_expr(expr: &ast::Expr, cb: &mut dyn FnMut(&ast::Expr)) {
164 match expr {
165 ast::Expr::BlockExpr(b) => {
166 match b.modifier() {
167 Some(
168 ast::BlockModifier::Async(_)
169 | ast::BlockModifier::Try(_)
170 | ast::BlockModifier::Const(_),
171 ) => return cb(expr),
172
173 Some(ast::BlockModifier::Label(label)) => {
174 for_each_break_expr(Some(label), b.stmt_list(), &mut |b| {
175 cb(&ast::Expr::BreakExpr(b))
176 });
177 }
178 Some(ast::BlockModifier::Unsafe(_)) => (),
179 None => (),
180 }
181 if let Some(stmt_list) = b.stmt_list() {
182 if let Some(e) = stmt_list.tail_expr() {
183 for_each_tail_expr(&e, cb);
184 }
185 }
186 }
187 ast::Expr::IfExpr(if_) => {
188 let mut if_ = if_.clone();
189 loop {
190 if let Some(block) = if_.then_branch() {
191 for_each_tail_expr(&ast::Expr::BlockExpr(block), cb);
192 }
193 match if_.else_branch() {
194 Some(ast::ElseBranch::IfExpr(it)) => if_ = it,
195 Some(ast::ElseBranch::Block(block)) => {
196 for_each_tail_expr(&ast::Expr::BlockExpr(block), cb);
197 break;
198 }
199 None => break,
200 }
201 }
202 }
203 ast::Expr::LoopExpr(l) => {
204 for_each_break_expr(l.label(), l.loop_body().and_then(|it| it.stmt_list()), &mut |b| {
205 cb(&ast::Expr::BreakExpr(b))
206 })
207 }
208 ast::Expr::MatchExpr(m) => {
209 if let Some(arms) = m.match_arm_list() {
210 arms.arms().filter_map(|arm| arm.expr()).for_each(|e| for_each_tail_expr(&e, cb));
211 }
212 }
213 ast::Expr::ArrayExpr(_)
214 | ast::Expr::AwaitExpr(_)
215 | ast::Expr::BinExpr(_)
216 | ast::Expr::BoxExpr(_)
217 | ast::Expr::BreakExpr(_)
218 | ast::Expr::CallExpr(_)
219 | ast::Expr::CastExpr(_)
220 | ast::Expr::ClosureExpr(_)
221 | ast::Expr::ContinueExpr(_)
222 | ast::Expr::FieldExpr(_)
223 | ast::Expr::ForExpr(_)
224 | ast::Expr::IndexExpr(_)
225 | ast::Expr::Literal(_)
226 | ast::Expr::MacroCall(_)
227 | ast::Expr::MacroStmts(_)
228 | ast::Expr::MethodCallExpr(_)
229 | ast::Expr::ParenExpr(_)
230 | ast::Expr::PathExpr(_)
231 | ast::Expr::PrefixExpr(_)
232 | ast::Expr::RangeExpr(_)
233 | ast::Expr::RecordExpr(_)
234 | ast::Expr::RefExpr(_)
235 | ast::Expr::ReturnExpr(_)
236 | ast::Expr::TryExpr(_)
237 | ast::Expr::TupleExpr(_)
238 | ast::Expr::WhileExpr(_)
239 | ast::Expr::YieldExpr(_) => cb(expr),
240 }
241 }
242
243 /// Calls `cb` on each break expr inside of `body` that is applicable for the given label.
for_each_break_expr( label: Option<ast::Label>, body: Option<ast::StmtList>, cb: &mut dyn FnMut(ast::BreakExpr), )244 pub fn for_each_break_expr(
245 label: Option<ast::Label>,
246 body: Option<ast::StmtList>,
247 cb: &mut dyn FnMut(ast::BreakExpr),
248 ) {
249 let label = label.and_then(|lbl| lbl.lifetime());
250 let mut depth = 0;
251 if let Some(b) = body {
252 let preorder = &mut b.syntax().preorder();
253 let ev_as_expr = |ev| match ev {
254 WalkEvent::Enter(it) => Some(WalkEvent::Enter(ast::Expr::cast(it)?)),
255 WalkEvent::Leave(it) => Some(WalkEvent::Leave(ast::Expr::cast(it)?)),
256 };
257 let eq_label = |lt: Option<ast::Lifetime>| {
258 lt.zip(label.as_ref()).map_or(false, |(lt, lbl)| lt.text() == lbl.text())
259 };
260 while let Some(node) = preorder.find_map(ev_as_expr) {
261 match node {
262 WalkEvent::Enter(expr) => match expr {
263 ast::Expr::LoopExpr(_) | ast::Expr::WhileExpr(_) | ast::Expr::ForExpr(_) => {
264 depth += 1
265 }
266 ast::Expr::BlockExpr(e) if e.label().is_some() => depth += 1,
267 ast::Expr::BreakExpr(b)
268 if (depth == 0 && b.lifetime().is_none()) || eq_label(b.lifetime()) =>
269 {
270 cb(b);
271 }
272 _ => (),
273 },
274 WalkEvent::Leave(expr) => match expr {
275 ast::Expr::LoopExpr(_) | ast::Expr::WhileExpr(_) | ast::Expr::ForExpr(_) => {
276 depth -= 1
277 }
278 ast::Expr::BlockExpr(e) if e.label().is_some() => depth -= 1,
279 _ => (),
280 },
281 }
282 }
283 }
284 }
285