aboutsummaryrefslogtreecommitdiff
path: root/crates/ra_hir/src/source_binder.rs
blob: 59046edcc414bc63d980c781b2be798beaf986e8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
//! Lookup hir elements using positions in the source code. This is a lossy
//! transformation: in general, a single source might correspond to several
//! modules, functions, etc, due to macros, cfgs and `#[path=]` attributes on
//! modules.
//!
//! So, this modules should not be used during hir construction, it exists
//! purely for "IDE needs".
use std::sync::Arc;

use hir_def::{
    expr::{ExprId, PatId},
    path::known,
};
use hir_expand::{name::AsName, Source};
use ra_db::FileId;
use ra_syntax::{
    ast::{self, AstNode},
    match_ast, AstPtr,
    SyntaxKind::*,
    SyntaxNode, SyntaxNodePtr, TextRange, TextUnit,
};
use rustc_hash::FxHashSet;

use crate::{
    db::HirDatabase,
    expr::{self, BodySourceMap, ExprScopes, ScopeId},
    ids::LocationCtx,
    resolve::{ScopeDef, TypeNs, ValueNs},
    ty::method_resolution::{self, implements_trait},
    AssocItem, Const, DefWithBody, Either, Enum, FromSource, Function, GenericParam, HasBody,
    HirFileId, Local, MacroDef, Module, Name, Path, Resolver, Static, Struct, Ty,
};

fn try_get_resolver_for_node(
    db: &impl HirDatabase,
    file_id: FileId,
    node: &SyntaxNode,
) -> Option<Resolver> {
    match_ast! {
        match node {
            ast::Module(it) => {
                let src = crate::Source { file_id: file_id.into(), ast: it };
                Some(crate::Module::from_declaration(db, src)?.resolver(db))
            },
             ast::SourceFile(it) => {
                let src =
                    crate::Source { file_id: file_id.into(), ast: crate::ModuleSource::SourceFile(it) };
                Some(crate::Module::from_definition(db, src)?.resolver(db))
            },
            ast::StructDef(it) => {
                let src = crate::Source { file_id: file_id.into(), ast: it };
                Some(Struct::from_source(db, src)?.resolver(db))
            },
            ast::EnumDef(it) => {
                let src = crate::Source { file_id: file_id.into(), ast: it };
                Some(Enum::from_source(db, src)?.resolver(db))
            },
            _ => {
                if node.kind() == FN_DEF || node.kind() == CONST_DEF || node.kind() == STATIC_DEF {
                    Some(def_with_body_from_child_node(db, file_id, node)?.resolver(db))
                } else {
                    // FIXME add missing cases
                    None
                }
            },
        }
    }
}

fn def_with_body_from_child_node(
    db: &impl HirDatabase,
    file_id: FileId,
    node: &SyntaxNode,
) -> Option<DefWithBody> {
    let src = crate::ModuleSource::from_child_node(db, file_id, node);
    let module = Module::from_definition(db, crate::Source { file_id: file_id.into(), ast: src })?;
    let ctx = LocationCtx::new(db, module.id, file_id.into());

    node.ancestors().find_map(|node| {
        match_ast! {
            match node {
                ast::FnDef(def)  => { Some(Function {id: ctx.to_def(&def) }.into()) },
                ast::ConstDef(def) => { Some(Const { id: ctx.to_def(&def) }.into()) },
                ast::StaticDef(def) => { Some(Static { id: ctx.to_def(&def) }.into()) },
                _ => { None },
            }
        }
    })
}

/// `SourceAnalyzer` is a convenience wrapper which exposes HIR API in terms of
/// original source files. It should not be used inside the HIR itself.
#[derive(Debug)]
pub struct SourceAnalyzer {
    // FIXME: this doesn't handle macros at all
    file_id: FileId,
    resolver: Resolver,
    body_owner: Option<DefWithBody>,
    body_source_map: Option<Arc<BodySourceMap>>,
    infer: Option<Arc<crate::ty::InferenceResult>>,
    scopes: Option<Arc<crate::expr::ExprScopes>>,
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub enum PathResolution {
    /// An item
    Def(crate::ModuleDef),
    /// A local binding (only value namespace)
    Local(Local),
    /// A generic parameter
    GenericParam(GenericParam),
    SelfType(crate::ImplBlock),
    Macro(MacroDef),
    AssocItem(crate::AssocItem),
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ScopeEntryWithSyntax {
    pub(crate) name: Name,
    pub(crate) ptr: Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>>,
}

impl ScopeEntryWithSyntax {
    pub fn name(&self) -> &Name {
        &self.name
    }

    pub fn ptr(&self) -> Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>> {
        self.ptr
    }
}

#[derive(Debug)]
pub struct ReferenceDescriptor {
    pub range: TextRange,
    pub name: String,
}

impl SourceAnalyzer {
    pub fn new(
        db: &impl HirDatabase,
        file_id: FileId,
        node: &SyntaxNode,
        offset: Option<TextUnit>,
    ) -> SourceAnalyzer {
        let def_with_body = def_with_body_from_child_node(db, file_id, node);
        if let Some(def) = def_with_body {
            let source_map = def.body_source_map(db);
            let scopes = def.expr_scopes(db);
            let scope = match offset {
                None => scope_for(&scopes, &source_map, file_id.into(), &node),
                Some(offset) => scope_for_offset(&scopes, &source_map, file_id.into(), offset),
            };
            let resolver = expr::resolver_for_scope(db, def, scope);
            SourceAnalyzer {
                resolver,
                body_owner: Some(def),
                body_source_map: Some(source_map),
                infer: Some(def.infer(db)),
                scopes: Some(scopes),
                file_id,
            }
        } else {
            SourceAnalyzer {
                resolver: node
                    .ancestors()
                    .find_map(|node| try_get_resolver_for_node(db, file_id, &node))
                    .unwrap_or_default(),
                body_owner: None,
                body_source_map: None,
                infer: None,
                scopes: None,
                file_id,
            }
        }
    }

    fn expr_id(&self, expr: &ast::Expr) -> Option<ExprId> {
        let src = Source { file_id: self.file_id.into(), ast: expr };
        self.body_source_map.as_ref()?.node_expr(src)
    }

    fn pat_id(&self, pat: &ast::Pat) -> Option<PatId> {
        let src = Source { file_id: self.file_id.into(), ast: pat };
        self.body_source_map.as_ref()?.node_pat(src)
    }

    pub fn type_of(&self, _db: &impl HirDatabase, expr: &ast::Expr) -> Option<crate::Ty> {
        let expr_id = self.expr_id(expr)?;
        Some(self.infer.as_ref()?[expr_id].clone())
    }

    pub fn type_of_pat(&self, _db: &impl HirDatabase, pat: &ast::Pat) -> Option<crate::Ty> {
        let pat_id = self.pat_id(pat)?;
        Some(self.infer.as_ref()?[pat_id].clone())
    }

    pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
        let expr_id = self.expr_id(&call.clone().into())?;
        self.infer.as_ref()?.method_resolution(expr_id)
    }

    pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<crate::StructField> {
        let expr_id = self.expr_id(&field.clone().into())?;
        self.infer.as_ref()?.field_resolution(expr_id)
    }

    pub fn resolve_record_literal(&self, record_lit: &ast::RecordLit) -> Option<crate::VariantDef> {
        let expr_id = self.expr_id(&record_lit.clone().into())?;
        self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
    }

    pub fn resolve_record_pattern(&self, record_pat: &ast::RecordPat) -> Option<crate::VariantDef> {
        let pat_id = self.pat_id(&record_pat.clone().into())?;
        self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
    }

    pub fn resolve_macro_call(
        &self,
        db: &impl HirDatabase,
        macro_call: &ast::MacroCall,
    ) -> Option<MacroDef> {
        // This must be a normal source file rather than macro file.
        let path = macro_call.path().and_then(Path::from_ast)?;
        self.resolver.resolve_path_as_macro(db, &path)
    }

    pub fn resolve_hir_path(
        &self,
        db: &impl HirDatabase,
        path: &crate::Path,
    ) -> Option<PathResolution> {
        let types = self.resolver.resolve_path_in_type_ns_fully(db, &path).map(|ty| match ty {
            TypeNs::SelfType(it) => PathResolution::SelfType(it),
            TypeNs::GenericParam(idx) => PathResolution::GenericParam(GenericParam {
                parent: self.resolver.generic_def().unwrap(),
                idx,
            }),
            TypeNs::AdtSelfType(it) | TypeNs::Adt(it) => PathResolution::Def(it.into()),
            TypeNs::EnumVariant(it) => PathResolution::Def(it.into()),
            TypeNs::TypeAlias(it) => PathResolution::Def(it.into()),
            TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
            TypeNs::Trait(it) => PathResolution::Def(it.into()),
        });
        let values = self.resolver.resolve_path_in_value_ns_fully(db, &path).and_then(|val| {
            let res = match val {
                ValueNs::LocalBinding(pat_id) => {
                    let var = Local { parent: self.body_owner?, pat_id };
                    PathResolution::Local(var)
                }
                ValueNs::Function(it) => PathResolution::Def(it.into()),
                ValueNs::Const(it) => PathResolution::Def(it.into()),
                ValueNs::Static(it) => PathResolution::Def(it.into()),
                ValueNs::Struct(it) => PathResolution::Def(it.into()),
                ValueNs::EnumVariant(it) => PathResolution::Def(it.into()),
            };
            Some(res)
        });

        let items = self
            .resolver
            .resolve_module_path(db, &path)
            .take_types()
            .map(|it| PathResolution::Def(it.into()));
        types.or(values).or(items).or_else(|| {
            self.resolver.resolve_path_as_macro(db, &path).map(|def| PathResolution::Macro(def))
        })
    }

    pub fn resolve_path(&self, db: &impl HirDatabase, path: &ast::Path) -> Option<PathResolution> {
        if let Some(path_expr) = path.syntax().parent().and_then(ast::PathExpr::cast) {
            let expr_id = self.expr_id(&path_expr.into())?;
            if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_expr(expr_id) {
                return Some(PathResolution::AssocItem(assoc));
            }
        }
        if let Some(path_pat) = path.syntax().parent().and_then(ast::PathPat::cast) {
            let pat_id = self.pat_id(&path_pat.into())?;
            if let Some(assoc) = self.infer.as_ref()?.assoc_resolutions_for_pat(pat_id) {
                return Some(PathResolution::AssocItem(assoc));
            }
        }
        // This must be a normal source file rather than macro file.
        let hir_path = crate::Path::from_ast(path.clone())?;
        self.resolve_hir_path(db, &hir_path)
    }

    pub fn resolve_local_name(&self, name_ref: &ast::NameRef) -> Option<ScopeEntryWithSyntax> {
        let mut shadowed = FxHashSet::default();
        let name = name_ref.as_name();
        let source_map = self.body_source_map.as_ref()?;
        let scopes = self.scopes.as_ref()?;
        let scope = scope_for(scopes, source_map, self.file_id.into(), name_ref.syntax());
        let ret = scopes
            .scope_chain(scope)
            .flat_map(|scope| scopes.entries(scope).iter())
            .filter(|entry| shadowed.insert(entry.name()))
            .filter(|entry| entry.name() == &name)
            .nth(0);
        ret.and_then(|entry| {
            Some(ScopeEntryWithSyntax {
                name: entry.name().clone(),
                ptr: source_map.pat_syntax(entry.pat())?.ast,
            })
        })
    }

    pub fn process_all_names(&self, db: &impl HirDatabase, f: &mut dyn FnMut(Name, ScopeDef)) {
        self.resolver.process_all_names(db, f)
    }

    pub fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
        // FIXME: at least, this should work with any DefWithBody, but ideally
        // this should be hir-based altogether
        let fn_def = pat.syntax().ancestors().find_map(ast::FnDef::cast).unwrap();
        let ptr = Either::A(AstPtr::new(&ast::Pat::from(pat.clone())));
        fn_def
            .syntax()
            .descendants()
            .filter_map(ast::NameRef::cast)
            .filter(|name_ref| match self.resolve_local_name(&name_ref) {
                None => false,
                Some(entry) => entry.ptr() == ptr,
            })
            .map(|name_ref| ReferenceDescriptor {
                name: name_ref.text().to_string(),
                range: name_ref.syntax().text_range(),
            })
            .collect()
    }

    pub fn iterate_method_candidates<T>(
        &self,
        db: &impl HirDatabase,
        ty: Ty,
        name: Option<&Name>,
        mut callback: impl FnMut(&Ty, Function) -> Option<T>,
    ) -> Option<T> {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
        let canonical = crate::ty::Canonical { value: ty, num_vars: 0 };
        method_resolution::iterate_method_candidates(
            &canonical,
            db,
            &self.resolver,
            name,
            method_resolution::LookupMode::MethodCall,
            |ty, it| match it {
                AssocItem::Function(f) => callback(ty, f),
                _ => None,
            },
        )
    }

    pub fn iterate_path_candidates<T>(
        &self,
        db: &impl HirDatabase,
        ty: Ty,
        name: Option<&Name>,
        callback: impl FnMut(&Ty, AssocItem) -> Option<T>,
    ) -> Option<T> {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
        let canonical = crate::ty::Canonical { value: ty, num_vars: 0 };
        method_resolution::iterate_method_candidates(
            &canonical,
            db,
            &self.resolver,
            name,
            method_resolution::LookupMode::Path,
            callback,
        )
    }

    pub fn autoderef<'a>(
        &'a self,
        db: &'a impl HirDatabase,
        ty: Ty,
    ) -> impl Iterator<Item = Ty> + 'a {
        // There should be no inference vars in types passed here
        // FIXME check that?
        let canonical = crate::ty::Canonical { value: ty, num_vars: 0 };
        crate::ty::autoderef(db, &self.resolver, canonical).map(|canonical| canonical.value)
    }

    /// Checks that particular type `ty` implements `std::future::Future`.
    /// This function is used in `.await` syntax completion.
    pub fn impls_future(&self, db: &impl HirDatabase, ty: Ty) -> bool {
        let std_future_path = known::std_future_future();

        let std_future_trait = match self.resolver.resolve_known_trait(db, &std_future_path) {
            Some(it) => it,
            _ => return false,
        };

        let krate = match self.resolver.krate() {
            Some(krate) => krate,
            _ => return false,
        };

        let canonical_ty = crate::ty::Canonical { value: ty, num_vars: 0 };
        implements_trait(&canonical_ty, db, &self.resolver, krate, std_future_trait)
    }

    #[cfg(test)]
    pub(crate) fn body_source_map(&self) -> Arc<BodySourceMap> {
        self.body_source_map.clone().unwrap()
    }

    #[cfg(test)]
    pub(crate) fn inference_result(&self) -> Arc<crate::ty::InferenceResult> {
        self.infer.clone().unwrap()
    }

    #[cfg(test)]
    pub(crate) fn scopes(&self) -> Arc<ExprScopes> {
        self.scopes.clone().unwrap()
    }
}

fn scope_for(
    scopes: &ExprScopes,
    source_map: &BodySourceMap,
    file_id: HirFileId,
    node: &SyntaxNode,
) -> Option<ScopeId> {
    node.ancestors()
        .filter_map(ast::Expr::cast)
        .filter_map(|it| source_map.node_expr(Source { file_id, ast: &it }))
        .find_map(|it| scopes.scope_for(it))
}

fn scope_for_offset(
    scopes: &ExprScopes,
    source_map: &BodySourceMap,
    file_id: HirFileId,
    offset: TextUnit,
) -> Option<ScopeId> {
    scopes
        .scope_by_expr()
        .iter()
        .filter_map(|(id, scope)| {
            let source = source_map.expr_syntax(*id)?;
            // FIXME: correctly handle macro expansion
            if source.file_id != file_id {
                return None;
            }
            let syntax_node_ptr =
                source.ast.either(|it| it.syntax_node_ptr(), |it| it.syntax_node_ptr());
            Some((syntax_node_ptr, scope))
        })
        // find containing scope
        .min_by_key(|(ptr, _scope)| {
            (!(ptr.range().start() <= offset && offset <= ptr.range().end()), ptr.range().len())
        })
        .map(|(ptr, scope)| adjust(scopes, source_map, ptr, file_id, offset).unwrap_or(*scope))
}

// XXX: during completion, cursor might be outside of any particular
// expression. Try to figure out the correct scope...
fn adjust(
    scopes: &ExprScopes,
    source_map: &BodySourceMap,
    ptr: SyntaxNodePtr,
    file_id: HirFileId,
    offset: TextUnit,
) -> Option<ScopeId> {
    let r = ptr.range();
    let child_scopes = scopes
        .scope_by_expr()
        .iter()
        .filter_map(|(id, scope)| {
            let source = source_map.expr_syntax(*id)?;
            // FIXME: correctly handle macro expansion
            if source.file_id != file_id {
                return None;
            }
            let syntax_node_ptr =
                source.ast.either(|it| it.syntax_node_ptr(), |it| it.syntax_node_ptr());
            Some((syntax_node_ptr, scope))
        })
        .map(|(ptr, scope)| (ptr.range(), scope))
        .filter(|(range, _)| range.start() <= offset && range.is_subrange(&r) && *range != r);

    child_scopes
        .max_by(|(r1, _), (r2, _)| {
            if r2.is_subrange(&r1) {
                std::cmp::Ordering::Greater
            } else if r1.is_subrange(&r2) {
                std::cmp::Ordering::Less
            } else {
                r1.start().cmp(&r2.start())
            }
        })
        .map(|(_ptr, scope)| *scope)
}