rust/crates/ra_hir/src/source_binder.rs
2019-12-23 21:56:10 +08:00

566 lines
21 KiB
Rust

//! 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 either::Either;
use hir_def::{
body::{
scope::{ExprScopes, ScopeId},
BodySourceMap,
},
expr::{ExprId, PatId},
nameres::ModuleSource,
path::path,
resolver::{self, resolver_for_scope, HasResolver, Resolver, TypeNs, ValueNs},
AssocItemId, DefWithBodyId,
};
use hir_expand::{
hygiene::Hygiene, name::AsName, AstId, HirFileId, InFile, MacroCallId, MacroCallKind,
};
use hir_ty::{
method_resolution::{self, implements_trait},
Canonical, InEnvironment, InferenceResult, TraitEnvironment, Ty,
};
use ra_prof::profile;
use ra_syntax::{
ast::{self, AstNode},
match_ast, AstPtr,
SyntaxKind::*,
SyntaxNode, SyntaxNodePtr, SyntaxToken, TextRange, TextUnit,
};
use crate::{
db::HirDatabase, Adt, AssocItem, Const, DefWithBody, Enum, EnumVariant, FromSource, Function,
ImplBlock, Local, MacroDef, Name, Path, ScopeDef, Static, Struct, Trait, Type, TypeAlias,
TypeParam,
};
fn try_get_resolver_for_node(db: &impl HirDatabase, node: InFile<&SyntaxNode>) -> Option<Resolver> {
match_ast! {
match (node.value) {
ast::Module(it) => {
let src = node.with_value(it);
Some(crate::Module::from_declaration(db, src)?.id.resolver(db))
},
ast::SourceFile(it) => {
let src = node.with_value(ModuleSource::SourceFile(it));
Some(crate::Module::from_definition(db, src)?.id.resolver(db))
},
ast::StructDef(it) => {
let src = node.with_value(it);
Some(Struct::from_source(db, src)?.id.resolver(db))
},
ast::EnumDef(it) => {
let src = node.with_value(it);
Some(Enum::from_source(db, src)?.id.resolver(db))
},
ast::ImplBlock(it) => {
let src = node.with_value(it);
Some(ImplBlock::from_source(db, src)?.id.resolver(db))
},
ast::TraitDef(it) => {
let src = node.with_value(it);
Some(Trait::from_source(db, src)?.id.resolver(db))
},
_ => match node.value.kind() {
FN_DEF | CONST_DEF | STATIC_DEF => {
let def = def_with_body_from_child_node(db, node)?;
let def = DefWithBodyId::from(def);
Some(def.resolver(db))
}
// FIXME add missing cases
_ => None
}
}
}
}
fn def_with_body_from_child_node(
db: &impl HirDatabase,
child: InFile<&SyntaxNode>,
) -> Option<DefWithBody> {
let _p = profile("def_with_body_from_child_node");
child.cloned().ancestors_with_macros(db).find_map(|node| {
let n = &node.value;
match_ast! {
match n {
ast::FnDef(def) => { return Function::from_source(db, node.with_value(def)).map(DefWithBody::from); },
ast::ConstDef(def) => { return Const::from_source(db, node.with_value(def)).map(DefWithBody::from); },
ast::StaticDef(def) => { return Static::from_source(db, node.with_value(def)).map(DefWithBody::from); },
_ => { 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 {
file_id: HirFileId,
resolver: Resolver,
body_owner: Option<DefWithBody>,
body_source_map: Option<Arc<BodySourceMap>>,
infer: Option<Arc<InferenceResult>>,
scopes: Option<Arc<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
TypeParam(TypeParam),
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,
}
#[derive(Debug)]
pub struct Expansion {
macro_call_id: MacroCallId,
}
impl Expansion {
pub fn map_token_down(
&self,
db: &impl HirDatabase,
token: InFile<&SyntaxToken>,
) -> Option<InFile<SyntaxToken>> {
let exp_info = self.file_id().expansion_info(db)?;
exp_info.map_token_down(token)
}
pub fn file_id(&self) -> HirFileId {
self.macro_call_id.as_file()
}
}
impl SourceAnalyzer {
pub fn new(
db: &impl HirDatabase,
node: InFile<&SyntaxNode>,
offset: Option<TextUnit>,
) -> SourceAnalyzer {
let _p = profile("SourceAnalyzer::new");
let def_with_body = def_with_body_from_child_node(db, node);
if let Some(def) = def_with_body {
let (_body, source_map) = db.body_with_source_map(def.into());
let scopes = db.expr_scopes(def.into());
let scope = match offset {
None => scope_for(&scopes, &source_map, node),
Some(offset) => scope_for_offset(&scopes, &source_map, node.with_value(offset)),
};
let resolver = resolver_for_scope(db, def.into(), scope);
SourceAnalyzer {
resolver,
body_owner: Some(def),
body_source_map: Some(source_map),
infer: Some(db.infer(def.into())),
scopes: Some(scopes),
file_id: node.file_id,
}
} else {
SourceAnalyzer {
resolver: node
.value
.ancestors()
.find_map(|it| try_get_resolver_for_node(db, node.with_value(&it)))
.unwrap_or_default(),
body_owner: None,
body_source_map: None,
infer: None,
scopes: None,
file_id: node.file_id,
}
}
}
fn expr_id(&self, expr: &ast::Expr) -> Option<ExprId> {
let src = InFile { file_id: self.file_id, value: expr };
self.body_source_map.as_ref()?.node_expr(src)
}
fn pat_id(&self, pat: &ast::Pat) -> Option<PatId> {
let src = InFile { file_id: self.file_id, value: pat };
self.body_source_map.as_ref()?.node_pat(src)
}
fn expand_expr(
&self,
db: &impl HirDatabase,
expr: InFile<&ast::Expr>,
) -> Option<InFile<ast::Expr>> {
let macro_call = ast::MacroCall::cast(expr.value.syntax().clone())?;
let macro_file =
self.body_source_map.as_ref()?.node_macro_file(expr.with_value(&macro_call))?;
let expanded = db.parse_or_expand(macro_file)?;
let kind = expanded.kind();
let expr = InFile::new(macro_file, ast::Expr::cast(expanded)?);
if ast::MacroCall::can_cast(kind) {
self.expand_expr(db, expr.as_ref())
} else {
Some(expr)
}
}
pub fn type_of(&self, db: &impl HirDatabase, expr: &ast::Expr) -> Option<Type> {
let expr_id = if let Some(expr) = self.expand_expr(db, InFile::new(self.file_id, expr)) {
self.body_source_map.as_ref()?.node_expr(expr.as_ref())?
} else {
self.expr_id(expr)?
};
let ty = self.infer.as_ref()?[expr_id].clone();
let environment = TraitEnvironment::lower(db, &self.resolver);
Some(Type { krate: self.resolver.krate()?, ty: InEnvironment { value: ty, environment } })
}
pub fn type_of_pat(&self, db: &impl HirDatabase, pat: &ast::Pat) -> Option<Type> {
let pat_id = self.pat_id(pat)?;
let ty = self.infer.as_ref()?[pat_id].clone();
let environment = TraitEnvironment::lower(db, &self.resolver);
Some(Type { krate: self.resolver.krate()?, ty: InEnvironment { value: ty, environment } })
}
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).map(Function::from)
}
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).map(|it| it.into())
}
pub fn resolve_record_field(&self, field: &ast::RecordField) -> Option<crate::StructField> {
let expr_id = match field.expr() {
Some(it) => self.expr_id(&it)?,
None => {
let src = InFile { file_id: self.file_id, value: field };
self.body_source_map.as_ref()?.field_init_shorthand_expr(src)?
}
};
self.infer.as_ref()?.record_field_resolution(expr_id).map(|it| it.into())
}
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).map(|it| it.into())
}
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).map(|it| it.into())
}
pub fn resolve_macro_call(
&self,
db: &impl HirDatabase,
macro_call: InFile<&ast::MacroCall>,
) -> Option<MacroDef> {
let hygiene = Hygiene::new(db, macro_call.file_id);
let path = macro_call.value.path().and_then(|ast| Path::from_src(ast, &hygiene))?;
self.resolver.resolve_path_as_macro(db, path.mod_path()).map(|it| it.into())
}
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.mod_path()).map(|ty| match ty {
TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => {
PathResolution::Def(Adt::from(it).into())
}
TypeNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
});
let values =
self.resolver.resolve_path_in_value_ns_fully(db, path.mod_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::FunctionId(it) => PathResolution::Def(Function::from(it).into()),
ValueNs::ConstId(it) => PathResolution::Def(Const::from(it).into()),
ValueNs::StaticId(it) => PathResolution::Def(Static::from(it).into()),
ValueNs::StructId(it) => PathResolution::Def(Struct::from(it).into()),
ValueNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
};
Some(res)
});
let items = self
.resolver
.resolve_module_path_in_items(db, path.mod_path())
.take_types()
.map(|it| PathResolution::Def(it.into()));
types.or(values).or(items).or_else(|| {
self.resolver
.resolve_path_as_macro(db, path.mod_path())
.map(|def| PathResolution::Macro(def.into()))
})
}
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.into()));
}
}
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.into()));
}
}
// 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)
}
fn resolve_local_name(&self, name_ref: &ast::NameRef) -> Option<ScopeEntryWithSyntax> {
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, InFile::new(self.file_id, name_ref.syntax()))?;
let entry = scopes.resolve_name_in_scope(scope, &name)?;
Some(ScopeEntryWithSyntax {
name: entry.name().clone(),
ptr: source_map.pat_syntax(entry.pat())?.value,
})
}
pub fn process_all_names(&self, db: &impl HirDatabase, f: &mut dyn FnMut(Name, ScopeDef)) {
self.resolver.process_all_names(db, &mut |name, def| {
let def = match def {
resolver::ScopeDef::PerNs(it) => it.into(),
resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(TypeParam { id }),
resolver::ScopeDef::Local(pat_id) => {
let parent = self.resolver.body_owner().unwrap().into();
ScopeDef::Local(Local { parent, pat_id })
}
};
f(name, def)
})
}
// FIXME: we only use this in `inline_local_variable` assist, ideally, we
// should switch to general reference search infra there.
pub fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
let fn_def = pat.syntax().ancestors().find_map(ast::FnDef::cast).unwrap();
let ptr = Either::Left(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: &Type,
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 = Canonical { value: ty.ty.value.clone(), num_vars: 0 };
method_resolution::iterate_method_candidates(
&canonical,
db,
&self.resolver,
name,
method_resolution::LookupMode::MethodCall,
|ty, it| match it {
AssocItemId::FunctionId(f) => callback(ty, f.into()),
_ => None,
},
)
}
pub fn iterate_path_candidates<T>(
&self,
db: &impl HirDatabase,
ty: &Type,
name: Option<&Name>,
mut 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 = Canonical { value: ty.ty.value.clone(), num_vars: 0 };
method_resolution::iterate_method_candidates(
&canonical,
db,
&self.resolver,
name,
method_resolution::LookupMode::Path,
|ty, it| callback(ty, it.into()),
)
}
/// 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: Type) -> bool {
let std_future_path = path![std::future::Future];
let std_future_trait = match self.resolver.resolve_known_trait(db, &std_future_path) {
Some(it) => it.into(),
_ => return false,
};
let krate = match self.resolver.krate() {
Some(krate) => krate,
_ => return false,
};
let canonical_ty = Canonical { value: ty.ty.value, num_vars: 0 };
implements_trait(&canonical_ty, db, &self.resolver, krate.into(), std_future_trait)
}
pub fn expand(
&self,
db: &impl HirDatabase,
macro_call: InFile<&ast::MacroCall>,
) -> Option<Expansion> {
let def = self.resolve_macro_call(db, macro_call)?.id;
let ast_id = AstId::new(
macro_call.file_id,
db.ast_id_map(macro_call.file_id).ast_id(macro_call.value),
);
Some(Expansion { macro_call_id: def.as_call_id(db, MacroCallKind::FnLike(ast_id)) })
}
}
fn scope_for(
scopes: &ExprScopes,
source_map: &BodySourceMap,
node: InFile<&SyntaxNode>,
) -> Option<ScopeId> {
node.value
.ancestors()
.filter_map(ast::Expr::cast)
.filter_map(|it| source_map.node_expr(InFile::new(node.file_id, &it)))
.find_map(|it| scopes.scope_for(it))
}
fn scope_for_offset(
scopes: &ExprScopes,
source_map: &BodySourceMap,
offset: InFile<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 != offset.file_id {
return None;
}
let syntax_node_ptr =
source.value.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.value && offset.value <= ptr.range().end()),
ptr.range().len(),
)
})
.map(|(ptr, scope)| {
adjust(scopes, source_map, ptr, offset.file_id, offset.value).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.value.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)
}