rust/crates/hir/src/semantics.rs

1209 lines
46 KiB
Rust

//! See `Semantics`.
mod source_to_def;
use std::{cell::RefCell, fmt};
use base_db::{FileId, FileRange};
use hir_def::{
body,
resolver::{self, HasResolver, Resolver, TypeNs},
AsMacroCall, FunctionId, TraitId, VariantId,
};
use hir_expand::{name::AsName, ExpansionInfo};
use hir_ty::{associated_type_shorthand_candidates, Interner};
use itertools::Itertools;
use rustc_hash::{FxHashMap, FxHashSet};
use smallvec::{smallvec, SmallVec};
use syntax::{
algo::skip_trivia_token,
ast::{self, HasAttrs, HasGenericParams, HasLoopBody},
match_ast, AstNode, Direction, SyntaxNode, SyntaxNodePtr, SyntaxToken, TextSize,
};
use crate::{
db::HirDatabase,
semantics::source_to_def::{ChildContainer, SourceToDefCache, SourceToDefCtx},
source_analyzer::{resolve_hir_path, resolve_hir_path_as_macro, SourceAnalyzer},
Access, AssocItem, Callable, ConstParam, Crate, Field, Function, HasSource, HirFileId, Impl,
InFile, Label, LifetimeParam, Local, MacroDef, Module, ModuleDef, Name, Path, ScopeDef, Trait,
Type, TypeAlias, TypeParam, VariantDef,
};
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum PathResolution {
/// An item
Def(ModuleDef),
/// A local binding (only value namespace)
Local(Local),
/// A type parameter
TypeParam(TypeParam),
/// A const parameter
ConstParam(ConstParam),
SelfType(Impl),
Macro(MacroDef),
AssocItem(AssocItem),
}
impl PathResolution {
fn in_type_ns(&self) -> Option<TypeNs> {
match self {
PathResolution::Def(ModuleDef::Adt(adt)) => Some(TypeNs::AdtId((*adt).into())),
PathResolution::Def(ModuleDef::BuiltinType(builtin)) => {
Some(TypeNs::BuiltinType((*builtin).into()))
}
PathResolution::Def(
ModuleDef::Const(_)
| ModuleDef::Variant(_)
| ModuleDef::Function(_)
| ModuleDef::Module(_)
| ModuleDef::Static(_)
| ModuleDef::Trait(_),
) => None,
PathResolution::Def(ModuleDef::TypeAlias(alias)) => {
Some(TypeNs::TypeAliasId((*alias).into()))
}
PathResolution::Local(_) | PathResolution::Macro(_) | PathResolution::ConstParam(_) => {
None
}
PathResolution::TypeParam(param) => Some(TypeNs::GenericParam((*param).into())),
PathResolution::SelfType(impl_def) => Some(TypeNs::SelfType((*impl_def).into())),
PathResolution::AssocItem(AssocItem::Const(_) | AssocItem::Function(_)) => None,
PathResolution::AssocItem(AssocItem::TypeAlias(alias)) => {
Some(TypeNs::TypeAliasId((*alias).into()))
}
}
}
/// Returns an iterator over associated types that may be specified after this path (using
/// `Ty::Assoc` syntax).
pub fn assoc_type_shorthand_candidates<R>(
&self,
db: &dyn HirDatabase,
mut cb: impl FnMut(&Name, TypeAlias) -> Option<R>,
) -> Option<R> {
associated_type_shorthand_candidates(db, self.in_type_ns()?, |name, _, id| {
cb(name, id.into())
})
}
}
#[derive(Debug)]
pub struct TypeInfo {
/// The original type of the expression or pattern.
pub original: Type,
/// The adjusted type, if an adjustment happened.
pub adjusted: Option<Type>,
}
impl TypeInfo {
pub fn original(self) -> Type {
self.original
}
pub fn has_adjustment(&self) -> bool {
self.adjusted.is_some()
}
/// The adjusted type, or the original in case no adjustments occurred.
pub fn adjusted(self) -> Type {
self.adjusted.unwrap_or(self.original)
}
}
/// Primary API to get semantic information, like types, from syntax trees.
pub struct Semantics<'db, DB> {
pub db: &'db DB,
imp: SemanticsImpl<'db>,
}
pub struct SemanticsImpl<'db> {
pub db: &'db dyn HirDatabase,
s2d_cache: RefCell<SourceToDefCache>,
expansion_info_cache: RefCell<FxHashMap<HirFileId, Option<ExpansionInfo>>>,
// Rootnode to HirFileId cache
cache: RefCell<FxHashMap<SyntaxNode, HirFileId>>,
// MacroCall to its expansion's HirFileId cache
macro_call_cache: RefCell<FxHashMap<InFile<ast::MacroCall>, HirFileId>>,
}
impl<DB> fmt::Debug for Semantics<'_, DB> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Semantics {{ ... }}")
}
}
impl<'db, DB: HirDatabase> Semantics<'db, DB> {
pub fn new(db: &DB) -> Semantics<DB> {
let impl_ = SemanticsImpl::new(db);
Semantics { db, imp: impl_ }
}
pub fn parse(&self, file_id: FileId) -> ast::SourceFile {
self.imp.parse(file_id)
}
pub fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
self.imp.expand(macro_call)
}
/// If `item` has an attribute macro attached to it, expands it.
pub fn expand_attr_macro(&self, item: &ast::Item) -> Option<SyntaxNode> {
self.imp.expand_attr_macro(item)
}
pub fn expand_derive_macro(&self, derive: &ast::Attr) -> Option<Vec<SyntaxNode>> {
self.imp.expand_derive_macro(derive)
}
pub fn is_attr_macro_call(&self, item: &ast::Item) -> bool {
self.imp.is_attr_macro_call(item)
}
pub fn speculative_expand(
&self,
actual_macro_call: &ast::MacroCall,
speculative_args: &ast::TokenTree,
token_to_map: SyntaxToken,
) -> Option<(SyntaxNode, SyntaxToken)> {
self.imp.speculative_expand(actual_macro_call, speculative_args, token_to_map)
}
pub fn speculative_expand_attr_macro(
&self,
actual_macro_call: &ast::Item,
speculative_args: &ast::Item,
token_to_map: SyntaxToken,
) -> Option<(SyntaxNode, SyntaxToken)> {
self.imp.speculative_expand_attr(actual_macro_call, speculative_args, token_to_map)
}
/// Descend the token into macrocalls to its first mapped counterpart.
pub fn descend_into_macros_single(&self, token: SyntaxToken) -> SyntaxToken {
self.imp.descend_into_macros_single(token)
}
/// Descend the token into macrocalls to all its mapped counterparts.
pub fn descend_into_macros(&self, token: SyntaxToken) -> SmallVec<[SyntaxToken; 1]> {
self.imp.descend_into_macros(token)
}
/// Maps a node down by mapping its first and last token down.
pub fn descend_node_into_attributes<N: AstNode>(&self, node: N) -> SmallVec<[N; 1]> {
self.imp.descend_node_into_attributes(node)
}
/// Search for a definition's source and cache its syntax tree
pub fn source<Def: HasSource>(&self, def: Def) -> Option<InFile<Def::Ast>>
where
Def::Ast: AstNode,
{
self.imp.source(def)
}
pub fn hir_file_for(&self, syntax_node: &SyntaxNode) -> HirFileId {
self.imp.find_file(syntax_node.clone()).file_id
}
pub fn original_range(&self, node: &SyntaxNode) -> FileRange {
self.imp.original_range(node)
}
pub fn original_range_opt(&self, node: &SyntaxNode) -> Option<FileRange> {
self.imp.original_range_opt(node)
}
pub fn original_ast_node<N: AstNode>(&self, node: N) -> Option<N> {
self.imp.original_ast_node(node)
}
pub fn diagnostics_display_range(&self, diagnostics: InFile<SyntaxNodePtr>) -> FileRange {
self.imp.diagnostics_display_range(diagnostics)
}
pub fn token_ancestors_with_macros(
&self,
token: SyntaxToken,
) -> impl Iterator<Item = SyntaxNode> + '_ {
token.parent().into_iter().flat_map(move |it| self.ancestors_with_macros(it))
}
pub fn ancestors_with_macros(&self, node: SyntaxNode) -> impl Iterator<Item = SyntaxNode> + '_ {
self.imp.ancestors_with_macros(node)
}
pub fn ancestors_at_offset_with_macros(
&self,
node: &SyntaxNode,
offset: TextSize,
) -> impl Iterator<Item = SyntaxNode> + '_ {
self.imp.ancestors_at_offset_with_macros(node, offset)
}
/// Find an AstNode by offset inside SyntaxNode, if it is inside *Macrofile*,
/// search up until it is of the target AstNode type
pub fn find_node_at_offset_with_macros<N: AstNode>(
&self,
node: &SyntaxNode,
offset: TextSize,
) -> Option<N> {
self.imp.ancestors_at_offset_with_macros(node, offset).find_map(N::cast)
}
/// Find an AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
/// descend it and find again
pub fn find_node_at_offset_with_descend<N: AstNode>(
&self,
node: &SyntaxNode,
offset: TextSize,
) -> Option<N> {
self.imp.descend_node_at_offset(node, offset).flatten().find_map(N::cast)
}
/// Find an AstNode by offset inside SyntaxNode, if it is inside *MacroCall*,
/// descend it and find again
pub fn find_nodes_at_offset_with_descend<'slf, N: AstNode + 'slf>(
&'slf self,
node: &SyntaxNode,
offset: TextSize,
) -> impl Iterator<Item = N> + 'slf {
self.imp.descend_node_at_offset(node, offset).filter_map(|mut it| it.find_map(N::cast))
}
pub fn resolve_lifetime_param(&self, lifetime: &ast::Lifetime) -> Option<LifetimeParam> {
self.imp.resolve_lifetime_param(lifetime)
}
pub fn resolve_label(&self, lifetime: &ast::Lifetime) -> Option<Label> {
self.imp.resolve_label(lifetime)
}
pub fn resolve_type(&self, ty: &ast::Type) -> Option<Type> {
self.imp.resolve_type(ty)
}
pub fn type_of_expr(&self, expr: &ast::Expr) -> Option<TypeInfo> {
self.imp.type_of_expr(expr)
}
pub fn type_of_pat(&self, pat: &ast::Pat) -> Option<TypeInfo> {
self.imp.type_of_pat(pat)
}
pub fn type_of_self(&self, param: &ast::SelfParam) -> Option<Type> {
self.imp.type_of_self(param)
}
pub fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<Function> {
self.imp.resolve_method_call(call).map(Function::from)
}
pub fn resolve_method_call_as_callable(&self, call: &ast::MethodCallExpr) -> Option<Callable> {
self.imp.resolve_method_call_as_callable(call)
}
pub fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
self.imp.resolve_field(field)
}
pub fn resolve_record_field(
&self,
field: &ast::RecordExprField,
) -> Option<(Field, Option<Local>, Type)> {
self.imp.resolve_record_field(field)
}
pub fn resolve_record_pat_field(&self, field: &ast::RecordPatField) -> Option<Field> {
self.imp.resolve_record_pat_field(field)
}
pub fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<MacroDef> {
self.imp.resolve_macro_call(macro_call)
}
pub fn resolve_attr_macro_call(&self, item: &ast::Item) -> Option<MacroDef> {
self.imp.resolve_attr_macro_call(item)
}
pub fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
self.imp.resolve_path(path)
}
pub fn resolve_path_as_macro(&self, path: &ast::Path) -> Option<MacroDef> {
self.imp.resolve_path_as_macro(path)
}
pub fn resolve_extern_crate(&self, extern_crate: &ast::ExternCrate) -> Option<Crate> {
self.imp.resolve_extern_crate(extern_crate)
}
pub fn resolve_variant(&self, record_lit: ast::RecordExpr) -> Option<VariantDef> {
self.imp.resolve_variant(record_lit).map(VariantDef::from)
}
pub fn resolve_bind_pat_to_const(&self, pat: &ast::IdentPat) -> Option<ModuleDef> {
self.imp.resolve_bind_pat_to_const(pat)
}
// FIXME: use this instead?
// pub fn resolve_name_ref(&self, name_ref: &ast::NameRef) -> Option<???>;
pub fn record_literal_missing_fields(&self, literal: &ast::RecordExpr) -> Vec<(Field, Type)> {
self.imp.record_literal_missing_fields(literal)
}
pub fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
self.imp.record_pattern_missing_fields(pattern)
}
pub fn to_def<T: ToDef>(&self, src: &T) -> Option<T::Def> {
let src = self.imp.find_file(src.syntax().clone()).with_value(src).cloned();
T::to_def(&self.imp, src)
}
pub fn to_module_def(&self, file: FileId) -> Option<Module> {
self.imp.to_module_def(file).next()
}
pub fn to_module_defs(&self, file: FileId) -> impl Iterator<Item = Module> {
self.imp.to_module_def(file)
}
pub fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
self.imp.scope(node)
}
pub fn scope_at_offset(&self, token: &SyntaxToken, offset: TextSize) -> SemanticsScope<'db> {
self.imp.scope_at_offset(&token.parent().unwrap(), offset)
}
pub fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
self.imp.scope_for_def(def)
}
pub fn assert_contains_node(&self, node: &SyntaxNode) {
self.imp.assert_contains_node(node)
}
pub fn is_unsafe_method_call(&self, method_call_expr: &ast::MethodCallExpr) -> bool {
self.imp.is_unsafe_method_call(method_call_expr)
}
pub fn is_unsafe_ref_expr(&self, ref_expr: &ast::RefExpr) -> bool {
self.imp.is_unsafe_ref_expr(ref_expr)
}
pub fn is_unsafe_ident_pat(&self, ident_pat: &ast::IdentPat) -> bool {
self.imp.is_unsafe_ident_pat(ident_pat)
}
}
impl<'db> SemanticsImpl<'db> {
fn new(db: &'db dyn HirDatabase) -> Self {
SemanticsImpl {
db,
s2d_cache: Default::default(),
cache: Default::default(),
expansion_info_cache: Default::default(),
macro_call_cache: Default::default(),
}
}
fn parse(&self, file_id: FileId) -> ast::SourceFile {
let tree = self.db.parse(file_id).tree();
self.cache(tree.syntax().clone(), file_id.into());
tree
}
fn expand(&self, macro_call: &ast::MacroCall) -> Option<SyntaxNode> {
let sa = self.analyze(macro_call.syntax());
let file_id = sa.expand(self.db, InFile::new(sa.file_id, macro_call))?;
let node = self.db.parse_or_expand(file_id)?;
self.cache(node.clone(), file_id);
Some(node)
}
fn expand_attr_macro(&self, item: &ast::Item) -> Option<SyntaxNode> {
let sa = self.analyze(item.syntax());
let src = InFile::new(sa.file_id, item.clone());
let macro_call_id = self.with_ctx(|ctx| ctx.item_to_macro_call(src))?;
let file_id = macro_call_id.as_file();
let node = self.db.parse_or_expand(file_id)?;
self.cache(node.clone(), file_id);
Some(node)
}
fn expand_derive_macro(&self, attr: &ast::Attr) -> Option<Vec<SyntaxNode>> {
let item = attr.syntax().parent().and_then(ast::Item::cast)?;
let sa = self.analyze(item.syntax());
let item = InFile::new(sa.file_id, &item);
let src = InFile::new(sa.file_id, attr.clone());
self.with_ctx(|ctx| {
let macro_call_ids = ctx.attr_to_derive_macro_call(item, src)?;
let expansions: Vec<_> = macro_call_ids
.iter()
.map(|call| call.as_file())
.flat_map(|file_id| {
let node = self.db.parse_or_expand(file_id)?;
self.cache(node.clone(), file_id);
Some(node)
})
.collect();
if expansions.is_empty() {
None
} else {
Some(expansions)
}
})
}
fn is_attr_macro_call(&self, item: &ast::Item) -> bool {
let sa = self.analyze(item.syntax());
let src = InFile::new(sa.file_id, item.clone());
self.with_ctx(|ctx| ctx.item_to_macro_call(src).is_some())
}
fn speculative_expand(
&self,
actual_macro_call: &ast::MacroCall,
speculative_args: &ast::TokenTree,
token_to_map: SyntaxToken,
) -> Option<(SyntaxNode, SyntaxToken)> {
let sa = self.analyze(actual_macro_call.syntax());
let macro_call = InFile::new(sa.file_id, actual_macro_call);
let krate = sa.resolver.krate()?;
let macro_call_id = macro_call.as_call_id(self.db.upcast(), krate, |path| {
sa.resolver.resolve_path_as_macro(self.db.upcast(), &path)
})?;
hir_expand::db::expand_speculative(
self.db.upcast(),
macro_call_id,
speculative_args.syntax(),
token_to_map,
)
}
fn speculative_expand_attr(
&self,
actual_macro_call: &ast::Item,
speculative_args: &ast::Item,
token_to_map: SyntaxToken,
) -> Option<(SyntaxNode, SyntaxToken)> {
let sa = self.analyze(actual_macro_call.syntax());
let macro_call = InFile::new(sa.file_id, actual_macro_call.clone());
let macro_call_id = self.with_ctx(|ctx| ctx.item_to_macro_call(macro_call))?;
hir_expand::db::expand_speculative(
self.db.upcast(),
macro_call_id,
speculative_args.syntax(),
token_to_map,
)
}
// This might not be the correct way to do this, but it works for now
fn descend_node_into_attributes<N: AstNode>(&self, node: N) -> SmallVec<[N; 1]> {
let mut res = smallvec![];
let tokens = (|| {
let first = skip_trivia_token(node.syntax().first_token()?, Direction::Next)?;
let last = skip_trivia_token(node.syntax().last_token()?, Direction::Prev)?;
Some((first, last))
})();
let (first, last) = match tokens {
Some(it) => it,
None => return res,
};
if first == last {
self.descend_into_macros_impl(
first,
|InFile { value, .. }| {
if let Some(node) = value.ancestors().find_map(N::cast) {
res.push(node)
}
},
false,
);
} else {
// Descend first and last token, then zip them to look for the node they belong to
let mut scratch: SmallVec<[_; 1]> = smallvec![];
self.descend_into_macros_impl(
first,
|token| {
scratch.push(token);
},
false,
);
let mut scratch = scratch.into_iter();
self.descend_into_macros_impl(
last,
|InFile { value: last, file_id: last_fid }| {
if let Some(InFile { value: first, file_id: first_fid }) = scratch.next() {
if first_fid == last_fid {
if let Some(p) = first.parent() {
let range = first.text_range().cover(last.text_range());
let node = find_root(&p)
.covering_element(range)
.ancestors()
.take_while(|it| it.text_range() == range)
.find_map(N::cast);
if let Some(node) = node {
res.push(node);
}
}
}
}
},
false,
);
}
res
}
fn descend_into_macros(&self, token: SyntaxToken) -> SmallVec<[SyntaxToken; 1]> {
let mut res = smallvec![];
self.descend_into_macros_impl(token, |InFile { value, .. }| res.push(value), false);
res
}
fn descend_into_macros_single(&self, token: SyntaxToken) -> SyntaxToken {
let mut res = token.clone();
self.descend_into_macros_impl(token, |InFile { value, .. }| res = value, true);
res
}
fn descend_into_macros_impl(
&self,
token: SyntaxToken,
mut f: impl FnMut(InFile<SyntaxToken>),
single: bool,
) {
let _p = profile::span("descend_into_macros");
let parent = match token.parent() {
Some(it) => it,
None => return,
};
let sa = self.analyze(&parent);
let mut stack: SmallVec<[_; 4]> = smallvec![InFile::new(sa.file_id, token)];
let mut cache = self.expansion_info_cache.borrow_mut();
let mut mcache = self.macro_call_cache.borrow_mut();
let mut process_expansion_for_token =
|stack: &mut SmallVec<_>, macro_file, item, token: InFile<&_>| {
let expansion_info = cache
.entry(macro_file)
.or_insert_with(|| macro_file.expansion_info(self.db.upcast()))
.as_ref()?;
{
let InFile { file_id, value } = expansion_info.expanded();
self.cache(value, file_id);
}
let mut mapped_tokens =
expansion_info.map_token_down(self.db.upcast(), item, token)?;
let len = stack.len();
// requeue the tokens we got from mapping our current token down
if single {
stack.extend(mapped_tokens.next());
} else {
stack.extend(mapped_tokens);
}
// if the length changed we have found a mapping for the token
(stack.len() != len).then(|| ())
};
// Remap the next token in the queue into a macro call its in, if it is not being remapped
// either due to not being in a macro-call or because its unused push it into the result vec,
// otherwise push the remapped tokens back into the queue as they can potentially be remapped again.
while let Some(token) = stack.pop() {
self.db.unwind_if_cancelled();
let was_not_remapped = (|| {
// are we inside an attribute macro call
let containing_attribute_macro_call = self.with_ctx(|ctx| {
token.value.ancestors().filter_map(ast::Item::cast).find_map(|item| {
if item.attrs().next().is_none() {
// Don't force populate the dyn cache for items that don't have an attribute anyways
return None;
}
Some((ctx.item_to_macro_call(token.with_value(item.clone()))?, item))
})
});
if let Some((call_id, item)) = containing_attribute_macro_call {
let file_id = call_id.as_file();
return process_expansion_for_token(
&mut stack,
file_id,
Some(item),
token.as_ref(),
);
}
// or are we inside a function-like macro call
if let Some(tt) =
// FIXME replace map.while_some with take_while once stable
token.value.ancestors().map(ast::TokenTree::cast).while_some().last()
{
let macro_call = tt.syntax().parent().and_then(ast::MacroCall::cast)?;
if tt.left_delimiter_token().map_or(false, |it| it == token.value) {
return None;
}
if tt.right_delimiter_token().map_or(false, |it| it == token.value) {
return None;
}
let mcall = token.with_value(macro_call);
let file_id = match mcache.get(&mcall) {
Some(&it) => it,
None => {
let it = sa.expand(self.db, mcall.as_ref())?;
mcache.insert(mcall, it);
it
}
};
return process_expansion_for_token(&mut stack, file_id, None, token.as_ref());
}
// outside of a macro invocation so this is a "final" token
None
})()
.is_none();
if was_not_remapped {
f(token)
}
}
}
// Note this return type is deliberate as [`find_nodes_at_offset_with_descend`] wants to stop
// traversing the inner iterator when it finds a node.
// The outer iterator is over the tokens descendants
// The inner iterator is the ancestors of a descendant
fn descend_node_at_offset(
&self,
node: &SyntaxNode,
offset: TextSize,
) -> impl Iterator<Item = impl Iterator<Item = SyntaxNode> + '_> + '_ {
node.token_at_offset(offset)
.map(move |token| self.descend_into_macros(token))
.map(|descendants| {
descendants.into_iter().map(move |it| self.token_ancestors_with_macros(it))
})
// re-order the tokens from token_at_offset by returning the ancestors with the smaller first nodes first
// See algo::ancestors_at_offset, which uses the same approach
.kmerge_by(|left, right| {
left.clone()
.map(|node| node.text_range().len())
.lt(right.clone().map(|node| node.text_range().len()))
})
}
fn original_range(&self, node: &SyntaxNode) -> FileRange {
let node = self.find_file(node.clone());
node.as_ref().original_file_range(self.db.upcast())
}
fn original_range_opt(&self, node: &SyntaxNode) -> Option<FileRange> {
let node = self.find_file(node.clone());
node.as_ref().original_file_range_opt(self.db.upcast())
}
fn original_ast_node<N: AstNode>(&self, node: N) -> Option<N> {
let file = self.find_file(node.syntax().clone());
file.with_value(node).original_ast_node(self.db.upcast()).map(|it| it.value)
}
fn diagnostics_display_range(&self, src: InFile<SyntaxNodePtr>) -> FileRange {
let root = self.db.parse_or_expand(src.file_id).unwrap();
let node = src.value.to_node(&root);
self.cache(root, src.file_id);
src.with_value(&node).original_file_range(self.db.upcast())
}
fn token_ancestors_with_macros(
&self,
token: SyntaxToken,
) -> impl Iterator<Item = SyntaxNode> + Clone + '_ {
token.parent().into_iter().flat_map(move |parent| self.ancestors_with_macros(parent))
}
fn ancestors_with_macros(
&self,
node: SyntaxNode,
) -> impl Iterator<Item = SyntaxNode> + Clone + '_ {
let node = self.find_file(node);
node.ancestors_with_macros(self.db.upcast()).map(|it| it.value)
}
fn ancestors_at_offset_with_macros(
&self,
node: &SyntaxNode,
offset: TextSize,
) -> impl Iterator<Item = SyntaxNode> + '_ {
node.token_at_offset(offset)
.map(|token| self.token_ancestors_with_macros(token))
.kmerge_by(|node1, node2| node1.text_range().len() < node2.text_range().len())
}
fn resolve_lifetime_param(&self, lifetime: &ast::Lifetime) -> Option<LifetimeParam> {
let text = lifetime.text();
let lifetime_param = lifetime.syntax().ancestors().find_map(|syn| {
let gpl = ast::AnyHasGenericParams::cast(syn)?.generic_param_list()?;
gpl.lifetime_params()
.find(|tp| tp.lifetime().as_ref().map(|lt| lt.text()).as_ref() == Some(&text))
})?;
let src = self.find_file(lifetime_param.syntax().clone()).with_value(lifetime_param);
ToDef::to_def(self, src)
}
fn resolve_label(&self, lifetime: &ast::Lifetime) -> Option<Label> {
let text = lifetime.text();
let label = lifetime.syntax().ancestors().find_map(|syn| {
let label = match_ast! {
match syn {
ast::ForExpr(it) => it.label(),
ast::WhileExpr(it) => it.label(),
ast::LoopExpr(it) => it.label(),
ast::BlockExpr(it) => it.label(),
_ => None,
}
};
label.filter(|l| {
l.lifetime()
.and_then(|lt| lt.lifetime_ident_token())
.map_or(false, |lt| lt.text() == text)
})
})?;
let src = self.find_file(label.syntax().clone()).with_value(label);
ToDef::to_def(self, src)
}
fn resolve_type(&self, ty: &ast::Type) -> Option<Type> {
let scope = self.scope(ty.syntax());
let ctx = body::LowerCtx::new(self.db.upcast(), scope.file_id);
let ty = hir_ty::TyLoweringContext::new(self.db, &scope.resolver)
.lower_ty(&crate::TypeRef::from_ast(&ctx, ty.clone()));
Type::new_with_resolver(self.db, &scope.resolver, ty)
}
fn type_of_expr(&self, expr: &ast::Expr) -> Option<TypeInfo> {
self.analyze(expr.syntax())
.type_of_expr(self.db, expr)
.map(|(ty, coerced)| TypeInfo { original: ty, adjusted: coerced })
}
fn type_of_pat(&self, pat: &ast::Pat) -> Option<TypeInfo> {
self.analyze(pat.syntax())
.type_of_pat(self.db, pat)
.map(|(ty, coerced)| TypeInfo { original: ty, adjusted: coerced })
}
fn type_of_self(&self, param: &ast::SelfParam) -> Option<Type> {
self.analyze(param.syntax()).type_of_self(self.db, param)
}
fn resolve_method_call(&self, call: &ast::MethodCallExpr) -> Option<FunctionId> {
self.analyze(call.syntax()).resolve_method_call(self.db, call).map(|(id, _)| id)
}
fn resolve_method_call_as_callable(&self, call: &ast::MethodCallExpr) -> Option<Callable> {
let (func, subst) = self.analyze(call.syntax()).resolve_method_call(self.db, call)?;
let ty = self.db.value_ty(func.into()).substitute(&Interner, &subst);
let resolver = self.analyze(call.syntax()).resolver;
let ty = Type::new_with_resolver(self.db, &resolver, ty)?;
let mut res = ty.as_callable(self.db)?;
res.is_bound_method = true;
Some(res)
}
fn resolve_field(&self, field: &ast::FieldExpr) -> Option<Field> {
self.analyze(field.syntax()).resolve_field(self.db, field)
}
fn resolve_record_field(
&self,
field: &ast::RecordExprField,
) -> Option<(Field, Option<Local>, Type)> {
self.analyze(field.syntax()).resolve_record_field(self.db, field)
}
fn resolve_record_pat_field(&self, field: &ast::RecordPatField) -> Option<Field> {
self.analyze(field.syntax()).resolve_record_pat_field(self.db, field)
}
fn resolve_macro_call(&self, macro_call: &ast::MacroCall) -> Option<MacroDef> {
let sa = self.analyze(macro_call.syntax());
let macro_call = self.find_file(macro_call.syntax().clone()).with_value(macro_call);
sa.resolve_macro_call(self.db, macro_call)
}
fn resolve_attr_macro_call(&self, item: &ast::Item) -> Option<MacroDef> {
let item_in_file = self.find_file(item.syntax().clone()).with_value(item.clone());
let macro_call_id = self.with_ctx(|ctx| ctx.item_to_macro_call(item_in_file))?;
Some(MacroDef { id: self.db.lookup_intern_macro(macro_call_id).def })
}
fn resolve_path(&self, path: &ast::Path) -> Option<PathResolution> {
self.analyze(path.syntax()).resolve_path(self.db, path)
}
// FIXME: This shouldn't exist, but is currently required to always resolve attribute paths in
// the IDE layer due to namespace collisions
fn resolve_path_as_macro(&self, path: &ast::Path) -> Option<MacroDef> {
self.analyze(path.syntax()).resolve_path_as_macro(self.db, path)
}
fn resolve_extern_crate(&self, extern_crate: &ast::ExternCrate) -> Option<Crate> {
let krate = self.scope(extern_crate.syntax()).krate()?;
krate.dependencies(self.db).into_iter().find_map(|dep| {
if dep.name == extern_crate.name_ref()?.as_name() {
Some(dep.krate)
} else {
None
}
})
}
fn resolve_variant(&self, record_lit: ast::RecordExpr) -> Option<VariantId> {
self.analyze(record_lit.syntax()).resolve_variant(self.db, record_lit)
}
fn resolve_bind_pat_to_const(&self, pat: &ast::IdentPat) -> Option<ModuleDef> {
self.analyze(pat.syntax()).resolve_bind_pat_to_const(self.db, pat)
}
fn record_literal_missing_fields(&self, literal: &ast::RecordExpr) -> Vec<(Field, Type)> {
self.analyze(literal.syntax())
.record_literal_missing_fields(self.db, literal)
.unwrap_or_default()
}
fn record_pattern_missing_fields(&self, pattern: &ast::RecordPat) -> Vec<(Field, Type)> {
self.analyze(pattern.syntax())
.record_pattern_missing_fields(self.db, pattern)
.unwrap_or_default()
}
fn with_ctx<F: FnOnce(&mut SourceToDefCtx) -> T, T>(&self, f: F) -> T {
let mut cache = self.s2d_cache.borrow_mut();
let mut ctx = SourceToDefCtx { db: self.db, cache: &mut *cache };
f(&mut ctx)
}
fn to_module_def(&self, file: FileId) -> impl Iterator<Item = Module> {
self.with_ctx(|ctx| ctx.file_to_def(file)).into_iter().map(Module::from)
}
fn scope(&self, node: &SyntaxNode) -> SemanticsScope<'db> {
let sa = self.analyze(node);
SemanticsScope { db: self.db, file_id: sa.file_id, resolver: sa.resolver }
}
fn scope_at_offset(&self, node: &SyntaxNode, offset: TextSize) -> SemanticsScope<'db> {
let sa = self.analyze_with_offset(node, offset);
SemanticsScope { db: self.db, file_id: sa.file_id, resolver: sa.resolver }
}
fn scope_for_def(&self, def: Trait) -> SemanticsScope<'db> {
let file_id = self.db.lookup_intern_trait(def.id).id.file_id();
let resolver = def.id.resolver(self.db.upcast());
SemanticsScope { db: self.db, file_id, resolver }
}
fn source<Def: HasSource>(&self, def: Def) -> Option<InFile<Def::Ast>>
where
Def::Ast: AstNode,
{
let res = def.source(self.db)?;
self.cache(find_root(res.value.syntax()), res.file_id);
Some(res)
}
fn analyze(&self, node: &SyntaxNode) -> SourceAnalyzer {
self.analyze_impl(node, None)
}
fn analyze_with_offset(&self, node: &SyntaxNode, offset: TextSize) -> SourceAnalyzer {
self.analyze_impl(node, Some(offset))
}
fn analyze_impl(&self, node: &SyntaxNode, offset: Option<TextSize>) -> SourceAnalyzer {
let _p = profile::span("Semantics::analyze_impl");
let node = self.find_file(node.clone());
let node = node.as_ref();
let container = match self.with_ctx(|ctx| ctx.find_container(node)) {
Some(it) => it,
None => return SourceAnalyzer::new_for_resolver(Resolver::default(), node),
};
let resolver = match container {
ChildContainer::DefWithBodyId(def) => {
return SourceAnalyzer::new_for_body(self.db, def, node, offset)
}
ChildContainer::TraitId(it) => it.resolver(self.db.upcast()),
ChildContainer::ImplId(it) => it.resolver(self.db.upcast()),
ChildContainer::ModuleId(it) => it.resolver(self.db.upcast()),
ChildContainer::EnumId(it) => it.resolver(self.db.upcast()),
ChildContainer::VariantId(it) => it.resolver(self.db.upcast()),
ChildContainer::TypeAliasId(it) => it.resolver(self.db.upcast()),
ChildContainer::GenericDefId(it) => it.resolver(self.db.upcast()),
};
SourceAnalyzer::new_for_resolver(resolver, node)
}
fn cache(&self, root_node: SyntaxNode, file_id: HirFileId) {
assert!(root_node.parent().is_none());
let mut cache = self.cache.borrow_mut();
let prev = cache.insert(root_node, file_id);
assert!(prev == None || prev == Some(file_id))
}
fn assert_contains_node(&self, node: &SyntaxNode) {
self.find_file(node.clone());
}
fn lookup(&self, root_node: &SyntaxNode) -> Option<HirFileId> {
let cache = self.cache.borrow();
cache.get(root_node).copied()
}
fn find_file(&self, node: SyntaxNode) -> InFile<SyntaxNode> {
let root_node = find_root(&node);
let file_id = self.lookup(&root_node).unwrap_or_else(|| {
panic!(
"\n\nFailed to lookup {:?} in this Semantics.\n\
Make sure to use only query nodes, derived from this instance of Semantics.\n\
root node: {:?}\n\
known nodes: {}\n\n",
node,
root_node,
self.cache
.borrow()
.keys()
.map(|it| format!("{:?}", it))
.collect::<Vec<_>>()
.join(", ")
)
});
InFile::new(file_id, node)
}
fn is_unsafe_method_call(&self, method_call_expr: &ast::MethodCallExpr) -> bool {
method_call_expr
.receiver()
.and_then(|expr| {
let field_expr = match expr {
ast::Expr::FieldExpr(field_expr) => field_expr,
_ => return None,
};
let ty = self.type_of_expr(&field_expr.expr()?)?.original;
if !ty.is_packed(self.db) {
return None;
}
let func = self.resolve_method_call(method_call_expr).map(Function::from)?;
let res = match func.self_param(self.db)?.access(self.db) {
Access::Shared | Access::Exclusive => true,
Access::Owned => false,
};
Some(res)
})
.unwrap_or(false)
}
fn is_unsafe_ref_expr(&self, ref_expr: &ast::RefExpr) -> bool {
ref_expr
.expr()
.and_then(|expr| {
let field_expr = match expr {
ast::Expr::FieldExpr(field_expr) => field_expr,
_ => return None,
};
let expr = field_expr.expr()?;
self.type_of_expr(&expr)
})
// Binding a reference to a packed type is possibly unsafe.
.map(|ty| ty.original.is_packed(self.db))
.unwrap_or(false)
// FIXME This needs layout computation to be correct. It will highlight
// more than it should with the current implementation.
}
fn is_unsafe_ident_pat(&self, ident_pat: &ast::IdentPat) -> bool {
if ident_pat.ref_token().is_none() {
return false;
}
ident_pat
.syntax()
.parent()
.and_then(|parent| {
// `IdentPat` can live under `RecordPat` directly under `RecordPatField` or
// `RecordPatFieldList`. `RecordPatField` also lives under `RecordPatFieldList`,
// so this tries to lookup the `IdentPat` anywhere along that structure to the
// `RecordPat` so we can get the containing type.
let record_pat = ast::RecordPatField::cast(parent.clone())
.and_then(|record_pat| record_pat.syntax().parent())
.or_else(|| Some(parent.clone()))
.and_then(|parent| {
ast::RecordPatFieldList::cast(parent)?
.syntax()
.parent()
.and_then(ast::RecordPat::cast)
});
// If this doesn't match a `RecordPat`, fallback to a `LetStmt` to see if
// this is initialized from a `FieldExpr`.
if let Some(record_pat) = record_pat {
self.type_of_pat(&ast::Pat::RecordPat(record_pat))
} else if let Some(let_stmt) = ast::LetStmt::cast(parent) {
let field_expr = match let_stmt.initializer()? {
ast::Expr::FieldExpr(field_expr) => field_expr,
_ => return None,
};
self.type_of_expr(&field_expr.expr()?)
} else {
None
}
})
// Binding a reference to a packed type is possibly unsafe.
.map(|ty| ty.original.is_packed(self.db))
.unwrap_or(false)
}
}
pub trait ToDef: AstNode + Clone {
type Def;
fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def>;
}
macro_rules! to_def_impls {
($(($def:path, $ast:path, $meth:ident)),* ,) => {$(
impl ToDef for $ast {
type Def = $def;
fn to_def(sema: &SemanticsImpl, src: InFile<Self>) -> Option<Self::Def> {
sema.with_ctx(|ctx| ctx.$meth(src)).map(<$def>::from)
}
}
)*}
}
to_def_impls![
(crate::Module, ast::Module, module_to_def),
(crate::Module, ast::SourceFile, source_file_to_def),
(crate::Struct, ast::Struct, struct_to_def),
(crate::Enum, ast::Enum, enum_to_def),
(crate::Union, ast::Union, union_to_def),
(crate::Trait, ast::Trait, trait_to_def),
(crate::Impl, ast::Impl, impl_to_def),
(crate::TypeAlias, ast::TypeAlias, type_alias_to_def),
(crate::Const, ast::Const, const_to_def),
(crate::Static, ast::Static, static_to_def),
(crate::Function, ast::Fn, fn_to_def),
(crate::Field, ast::RecordField, record_field_to_def),
(crate::Field, ast::TupleField, tuple_field_to_def),
(crate::Variant, ast::Variant, enum_variant_to_def),
(crate::TypeParam, ast::TypeParam, type_param_to_def),
(crate::LifetimeParam, ast::LifetimeParam, lifetime_param_to_def),
(crate::ConstParam, ast::ConstParam, const_param_to_def),
(crate::MacroDef, ast::Macro, macro_to_def),
(crate::Local, ast::IdentPat, bind_pat_to_def),
(crate::Local, ast::SelfParam, self_param_to_def),
(crate::Label, ast::Label, label_to_def),
(crate::Adt, ast::Adt, adt_to_def),
];
fn find_root(node: &SyntaxNode) -> SyntaxNode {
node.ancestors().last().unwrap()
}
/// `SemanticScope` encapsulates the notion of a scope (the set of visible
/// names) at a particular program point.
///
/// It is a bit tricky, as scopes do not really exist inside the compiler.
/// Rather, the compiler directly computes for each reference the definition it
/// refers to. It might transiently compute the explicit scope map while doing
/// so, but, generally, this is not something left after the analysis.
///
/// However, we do very much need explicit scopes for IDE purposes --
/// completion, at its core, lists the contents of the current scope. The notion
/// of scope is also useful to answer questions like "what would be the meaning
/// of this piece of code if we inserted it into this position?".
///
/// So `SemanticsScope` is constructed from a specific program point (a syntax
/// node or just a raw offset) and provides access to the set of visible names
/// on a somewhat best-effort basis.
///
/// Note that if you are wondering "what does this specific existing name mean?",
/// you'd better use the `resolve_` family of methods.
#[derive(Debug)]
pub struct SemanticsScope<'a> {
pub db: &'a dyn HirDatabase,
file_id: HirFileId,
resolver: Resolver,
}
impl<'a> SemanticsScope<'a> {
pub fn module(&self) -> Option<Module> {
Some(Module { id: self.resolver.module()? })
}
pub fn krate(&self) -> Option<Crate> {
Some(Crate { id: self.resolver.krate()? })
}
/// Note: `FxHashSet<TraitId>` should be treated as an opaque type, passed into `Type
// FIXME: rename to visible_traits to not repeat scope?
pub fn traits_in_scope(&self) -> FxHashSet<TraitId> {
let resolver = &self.resolver;
resolver.traits_in_scope(self.db.upcast())
}
pub fn process_all_names(&self, f: &mut dyn FnMut(Name, ScopeDef)) {
let scope = self.resolver.names_in_scope(self.db.upcast());
for (name, entries) in scope {
for entry in entries {
let def = match entry {
resolver::ScopeDef::ModuleDef(it) => ScopeDef::ModuleDef(it.into()),
resolver::ScopeDef::MacroDef(it) => ScopeDef::MacroDef(it.into()),
resolver::ScopeDef::Unknown => ScopeDef::Unknown,
resolver::ScopeDef::ImplSelfType(it) => ScopeDef::ImplSelfType(it.into()),
resolver::ScopeDef::AdtSelfType(it) => ScopeDef::AdtSelfType(it.into()),
resolver::ScopeDef::GenericParam(id) => ScopeDef::GenericParam(id.into()),
resolver::ScopeDef::Local(pat_id) => {
let parent = self.resolver.body_owner().unwrap();
ScopeDef::Local(Local { parent, pat_id })
}
resolver::ScopeDef::Label(label_id) => {
let parent = self.resolver.body_owner().unwrap();
ScopeDef::Label(Label { parent, label_id })
}
};
f(name.clone(), def)
}
}
}
/// Resolve a path as-if it was written at the given scope. This is
/// necessary a heuristic, as it doesn't take hygiene into account.
pub fn speculative_resolve(&self, path: &ast::Path) -> Option<PathResolution> {
let ctx = body::LowerCtx::new(self.db.upcast(), self.file_id);
let path = Path::from_src(path.clone(), &ctx)?;
resolve_hir_path(self.db, &self.resolver, &path)
}
/// Resolve a path as-if it was written at the given scope. This is
/// necessary a heuristic, as it doesn't take hygiene into account.
// FIXME: This special casing solely exists for attributes for now
// ideally we should have a path resolution infra that properly knows about overlapping namespaces
pub fn speculative_resolve_as_mac(&self, path: &ast::Path) -> Option<MacroDef> {
let ctx = body::LowerCtx::new(self.db.upcast(), self.file_id);
let path = Path::from_src(path.clone(), &ctx)?;
resolve_hir_path_as_macro(self.db, &self.resolver, &path)
}
}