//! 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::{iter::once, sync::Arc};
use hir_def::{
body::{
self,
scope::{ExprScopes, ScopeId},
Body, BodySourceMap,
},
expr::{ExprId, Pat, PatId},
path::{ModPath, Path, PathKind},
resolver::{resolver_for_scope, Resolver, TypeNs, ValueNs},
AsMacroCall, DefWithBodyId, FieldId, FunctionId, LocalFieldId, VariantId,
};
use hir_expand::{hygiene::Hygiene, name::AsName, HirFileId, InFile};
use hir_ty::{
diagnostics::{record_literal_missing_fields, record_pattern_missing_fields},
InferenceResult, Interner, Substitution, TyExt, TyLoweringContext,
};
use syntax::{
ast::{self, AstNode},
SyntaxNode, TextRange, TextSize,
};
use crate::{
db::HirDatabase, semantics::PathResolution, Adt, BuiltinType, Const, Field, Function, Local,
MacroDef, ModuleDef, Static, Struct, Trait, Type, TypeAlias, TypeParam, Variant,
};
use base_db::CrateId;
/// `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(crate) struct SourceAnalyzer {
pub(crate) file_id: HirFileId,
pub(crate) resolver: Resolver,
body: Option<Arc<Body>>,
body_source_map: Option<Arc<BodySourceMap>>,
infer: Option<Arc<InferenceResult>>,
scopes: Option<Arc<ExprScopes>>,
}
impl SourceAnalyzer {
pub(crate) fn new_for_body(
db: &dyn HirDatabase,
def: DefWithBodyId,
node: InFile<&SyntaxNode>,
offset: Option<TextSize>,
) -> SourceAnalyzer {
let (body, source_map) = db.body_with_source_map(def);
let scopes = db.expr_scopes(def);
let scope = match offset {
None => scope_for(&scopes, &source_map, node),
Some(offset) => scope_for_offset(db, &scopes, &source_map, node.with_value(offset)),
};
let resolver = resolver_for_scope(db.upcast(), def, scope);
SourceAnalyzer {
resolver,
body: Some(body),
body_source_map: Some(source_map),
infer: Some(db.infer(def)),
scopes: Some(scopes),
file_id: node.file_id,
}
}
pub(crate) fn new_for_resolver(
resolver: Resolver,
node: InFile<&SyntaxNode>,
) -> SourceAnalyzer {
SourceAnalyzer {
resolver,
body: None,
body_source_map: None,
infer: None,
scopes: None,
file_id: node.file_id,
}
}
fn expr_id(&self, db: &dyn HirDatabase, expr: &ast::Expr) -> Option<ExprId> {
let src = match expr {
ast::Expr::MacroCall(call) => {
self.expand_expr(db, InFile::new(self.file_id, call.clone()))?
}
_ => InFile::new(self.file_id, expr.clone()),
};
let sm = self.body_source_map.as_ref()?;
sm.node_expr(src.as_ref())
}
fn pat_id(&self, pat: &ast::Pat) -> Option<PatId> {
// FIXME: macros, see `expr_id`
let src = InFile { file_id: self.file_id, value: pat };
self.body_source_map.as_ref()?.node_pat(src)
}
fn expand_expr(
&self,
db: &dyn HirDatabase,
expr: InFile<ast::MacroCall>,
) -> Option<InFile<ast::Expr>> {
let macro_file = self.body_source_map.as_ref()?.node_macro_file(expr.as_ref())?;
let expanded = db.parse_or_expand(macro_file)?;
let res = match ast::MacroCall::cast(expanded.clone()) {
Some(call) => self.expand_expr(db, InFile::new(macro_file, call))?,
_ => InFile::new(macro_file, ast::Expr::cast(expanded)?),
};
Some(res)
}
pub(crate) fn type_of_expr(&self, db: &dyn HirDatabase, expr: &ast::Expr) -> Option<Type> {
let expr_id = self.expr_id(db, expr)?;
let ty = self.infer.as_ref()?[expr_id].clone();
Type::new_with_resolver(db, &self.resolver, ty)
}
pub(crate) fn type_of_pat(&self, db: &dyn HirDatabase, pat: &ast::Pat) -> Option<Type> {
let pat_id = self.pat_id(pat)?;
let ty = self.infer.as_ref()?[pat_id].clone();
Type::new_with_resolver(db, &self.resolver, ty)
}
pub(crate) fn type_of_self(
&self,
db: &dyn HirDatabase,
param: &ast::SelfParam,
) -> Option<Type> {
let src = InFile { file_id: self.file_id, value: param };
let pat_id = self.body_source_map.as_ref()?.node_self_param(src)?;
let ty = self.infer.as_ref()?[pat_id].clone();
Type::new_with_resolver(db, &self.resolver, ty)
}
pub(crate) fn resolve_method_call(
&self,
db: &dyn HirDatabase,
call: &ast::MethodCallExpr,
) -> Option<(FunctionId, Substitution)> {
let expr_id = self.expr_id(db, &call.clone().into())?;
self.infer.as_ref()?.method_resolution(expr_id)
}
pub(crate) fn resolve_field(
&self,
db: &dyn HirDatabase,
field: &ast::FieldExpr,
) -> Option<Field> {
let expr_id = self.expr_id(db, &field.clone().into())?;
self.infer.as_ref()?.field_resolution(expr_id).map(|it| it.into())
}
pub(crate) fn resolve_record_field(
&self,
db: &dyn HirDatabase,
field: &ast::RecordExprField,
) -> Option<(Field, Option<Local>, Type)> {
let record_expr = ast::RecordExpr::cast(field.syntax().parent().and_then(|p| p.parent())?)?;
let expr = ast::Expr::from(record_expr);
let expr_id = self.body_source_map.as_ref()?.node_expr(InFile::new(self.file_id, &expr))?;
let local_name = field.field_name()?.as_name();
let local = if field.name_ref().is_some() {
None
} else {
let path = ModPath::from_segments(PathKind::Plain, once(local_name.clone()));
match self.resolver.resolve_path_in_value_ns_fully(db.upcast(), &path) {
Some(ValueNs::LocalBinding(pat_id)) => {
Some(Local { pat_id, parent: self.resolver.body_owner()? })
}
_ => None,
}
};
let (_, subst) = self.infer.as_ref()?.type_of_expr.get(expr_id)?.as_adt()?;
let variant = self.infer.as_ref()?.variant_resolution_for_expr(expr_id)?;
let variant_data = variant.variant_data(db.upcast());
let field = FieldId { parent: variant, local_id: variant_data.field(&local_name)? };
let field_ty =
db.field_types(variant).get(field.local_id)?.clone().substitute(&Interner, subst);
Some((field.into(), local, Type::new_with_resolver(db, &self.resolver, field_ty)?))
}
pub(crate) fn resolve_record_pat_field(
&self,
db: &dyn HirDatabase,
field: &ast::RecordPatField,
) -> Option<Field> {
let field_name = field.field_name()?.as_name();
let record_pat = ast::RecordPat::cast(field.syntax().parent().and_then(|p| p.parent())?)?;
let pat_id = self.pat_id(&record_pat.into())?;
let variant = self.infer.as_ref()?.variant_resolution_for_pat(pat_id)?;
let variant_data = variant.variant_data(db.upcast());
let field = FieldId { parent: variant, local_id: variant_data.field(&field_name)? };
Some(field.into())
}
pub(crate) fn resolve_macro_call(
&self,
db: &dyn HirDatabase,
macro_call: InFile<&ast::MacroCall>,
) -> Option<MacroDef> {
let ctx = body::LowerCtx::new(db.upcast(), macro_call.file_id);
let path = macro_call.value.path().and_then(|ast| Path::from_src(ast, &ctx))?;
self.resolver.resolve_path_as_macro(db.upcast(), path.mod_path()).map(|it| it.into())
}
pub(crate) fn resolve_bind_pat_to_const(
&self,
db: &dyn HirDatabase,
pat: &ast::IdentPat,
) -> Option<ModuleDef> {
let pat_id = self.pat_id(&pat.clone().into())?;
let body = self.body.as_ref()?;
let path = match &body[pat_id] {
Pat::Path(path) => path,
_ => return None,
};
let res = resolve_hir_path(db, &self.resolver, path)?;
match res {
PathResolution::Def(def) => Some(def),
_ => None,
}
}
pub(crate) fn resolve_path(
&self,
db: &dyn HirDatabase,
path: &ast::Path,
) -> Option<PathResolution> {
let parent = || path.syntax().parent();
let mut prefer_value_ns = false;
if let Some(path_expr) = parent().and_then(ast::PathExpr::cast) {
let expr_id = self.expr_id(db, &path_expr.into())?;
let infer = self.infer.as_ref()?;
if let Some(assoc) = infer.assoc_resolutions_for_expr(expr_id) {
return Some(PathResolution::AssocItem(assoc.into()));
}
if let Some(VariantId::EnumVariantId(variant)) =
infer.variant_resolution_for_expr(expr_id)
{
return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
}
prefer_value_ns = true;
}
if let Some(path_pat) = 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()));
}
if let Some(VariantId::EnumVariantId(variant)) =
self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
{
return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
}
}
if let Some(rec_lit) = parent().and_then(ast::RecordExpr::cast) {
let expr_id = self.expr_id(db, &rec_lit.into())?;
if let Some(VariantId::EnumVariantId(variant)) =
self.infer.as_ref()?.variant_resolution_for_expr(expr_id)
{
return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
}
}
if let Some(pat) = parent()
.and_then(ast::RecordPat::cast)
.map(ast::Pat::from)
.or_else(|| parent().and_then(ast::TupleStructPat::cast).map(ast::Pat::from))
{
let pat_id = self.pat_id(&pat)?;
if let Some(VariantId::EnumVariantId(variant)) =
self.infer.as_ref()?.variant_resolution_for_pat(pat_id)
{
return Some(PathResolution::Def(ModuleDef::Variant(variant.into())));
}
}
// This must be a normal source file rather than macro file.
let hygiene = Hygiene::new(db.upcast(), self.file_id);
let ctx = body::LowerCtx::with_hygiene(db.upcast(), &hygiene);
let hir_path = Path::from_src(path.clone(), &ctx)?;
// Case where path is a qualifier of another path, e.g. foo::bar::Baz where we are
// trying to resolve foo::bar.
if let Some(outer_path) = parent().and_then(ast::Path::cast) {
if let Some(qualifier) = outer_path.qualifier() {
if path == &qualifier {
return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
}
}
}
// Case where path is a qualifier of a use tree, e.g. foo::bar::{Baz, Qux} where we are
// trying to resolve foo::bar.
if let Some(use_tree) = parent().and_then(ast::UseTree::cast) {
if let Some(qualifier) = use_tree.path() {
if path == &qualifier && use_tree.coloncolon_token().is_some() {
return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
}
}
}
if parent().map_or(false, |it| ast::Visibility::can_cast(it.kind())) {
resolve_hir_path_qualifier(db, &self.resolver, &hir_path)
} else {
resolve_hir_path_(db, &self.resolver, &hir_path, prefer_value_ns)
}
}
pub(crate) fn record_literal_missing_fields(
&self,
db: &dyn HirDatabase,
literal: &ast::RecordExpr,
) -> Option<Vec<(Field, Type)>> {
let krate = self.resolver.krate()?;
let body = self.body.as_ref()?;
let infer = self.infer.as_ref()?;
let expr_id = self.expr_id(db, &literal.clone().into())?;
let substs = infer.type_of_expr[expr_id].as_adt()?.1;
let (variant, missing_fields, _exhaustive) =
record_literal_missing_fields(db, infer, expr_id, &body[expr_id])?;
let res = self.missing_fields(db, krate, substs, variant, missing_fields);
Some(res)
}
pub(crate) fn record_pattern_missing_fields(
&self,
db: &dyn HirDatabase,
pattern: &ast::RecordPat,
) -> Option<Vec<(Field, Type)>> {
let krate = self.resolver.krate()?;
let body = self.body.as_ref()?;
let infer = self.infer.as_ref()?;
let pat_id = self.pat_id(&pattern.clone().into())?;
let substs = infer.type_of_pat[pat_id].as_adt()?.1;
let (variant, missing_fields, _exhaustive) =
record_pattern_missing_fields(db, infer, pat_id, &body[pat_id])?;
let res = self.missing_fields(db, krate, substs, variant, missing_fields);
Some(res)
}
fn missing_fields(
&self,
db: &dyn HirDatabase,
krate: CrateId,
substs: &Substitution,
variant: VariantId,
missing_fields: Vec<LocalFieldId>,
) -> Vec<(Field, Type)> {
let field_types = db.field_types(variant);
missing_fields
.into_iter()
.map(|local_id| {
let field = FieldId { parent: variant, local_id };
let ty = field_types[local_id].clone().substitute(&Interner, substs);
(field.into(), Type::new_with_resolver_inner(db, krate, &self.resolver, ty))
})
.collect()
}
pub(crate) fn expand(
&self,
db: &dyn HirDatabase,
macro_call: InFile<&ast::MacroCall>,
) -> Option<HirFileId> {
let krate = self.resolver.krate()?;
let macro_call_id = macro_call.as_call_id(db.upcast(), krate, |path| {
self.resolver.resolve_path_as_macro(db.upcast(), &path)
})?;
Some(macro_call_id.as_file()).filter(|it| it.expansion_level(db.upcast()) < 64)
}
pub(crate) fn resolve_variant(
&self,
db: &dyn HirDatabase,
record_lit: ast::RecordExpr,
) -> Option<VariantId> {
let infer = self.infer.as_ref()?;
let expr_id = self.expr_id(db, &record_lit.into())?;
infer.variant_resolution_for_expr(expr_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(
db: &dyn HirDatabase,
scopes: &ExprScopes,
source_map: &BodySourceMap,
offset: InFile<TextSize>,
) -> Option<ScopeId> {
scopes
.scope_by_expr()
.iter()
.filter_map(|(id, scope)| {
let source = source_map.expr_syntax(*id).ok()?;
// FIXME: correctly handle macro expansion
if source.file_id != offset.file_id {
return None;
}
let root = source.file_syntax(db.upcast());
let node = source.value.to_node(&root);
Some((node.syntax().text_range(), scope))
})
// find containing scope
.min_by_key(|(expr_range, _scope)| {
(
!(expr_range.start() <= offset.value && offset.value <= expr_range.end()),
expr_range.len(),
)
})
.map(|(expr_range, scope)| {
adjust(db, scopes, source_map, expr_range, offset).unwrap_or(*scope)
})
}
// XXX: during completion, cursor might be outside of any particular
// expression. Try to figure out the correct scope...
fn adjust(
db: &dyn HirDatabase,
scopes: &ExprScopes,
source_map: &BodySourceMap,
expr_range: TextRange,
offset: InFile<TextSize>,
) -> Option<ScopeId> {
let child_scopes = scopes
.scope_by_expr()
.iter()
.filter_map(|(id, scope)| {
let source = source_map.expr_syntax(*id).ok()?;
// FIXME: correctly handle macro expansion
if source.file_id != offset.file_id {
return None;
}
let root = source.file_syntax(db.upcast());
let node = source.value.to_node(&root);
Some((node.syntax().text_range(), scope))
})
.filter(|&(range, _)| {
range.start() <= offset.value && expr_range.contains_range(range) && range != expr_range
});
child_scopes
.max_by(|&(r1, _), &(r2, _)| {
if r1.contains_range(r2) {
std::cmp::Ordering::Greater
} else if r2.contains_range(r1) {
std::cmp::Ordering::Less
} else {
r1.start().cmp(&r2.start())
}
})
.map(|(_ptr, scope)| *scope)
}
#[inline]
pub(crate) fn resolve_hir_path(
db: &dyn HirDatabase,
resolver: &Resolver,
path: &Path,
) -> Option<PathResolution> {
resolve_hir_path_(db, resolver, path, false)
}
fn resolve_hir_path_(
db: &dyn HirDatabase,
resolver: &Resolver,
path: &Path,
prefer_value_ns: bool,
) -> Option<PathResolution> {
let types = || {
let (ty, unresolved) = match path.type_anchor() {
Some(type_ref) => {
let (_, res) = TyLoweringContext::new(db, resolver).lower_ty_ext(type_ref);
res.map(|ty_ns| (ty_ns, path.segments().first()))
}
None => {
let (ty, remaining) =
resolver.resolve_path_in_type_ns(db.upcast(), path.mod_path())?;
match remaining {
Some(remaining) if remaining > 1 => None,
_ => Some((ty, path.segments().get(1))),
}
}
}?;
let res = 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(Variant::from(it).into()),
TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
};
match unresolved {
Some(unresolved) => res
.assoc_type_shorthand_candidates(db, |name, alias| {
(name == unresolved.name).then(|| alias)
})
.map(TypeAlias::from)
.map(Into::into)
.map(PathResolution::Def),
None => Some(res),
}
};
let body_owner = resolver.body_owner();
let values = || {
resolver.resolve_path_in_value_ns_fully(db.upcast(), path.mod_path()).and_then(|val| {
let res = match val {
ValueNs::LocalBinding(pat_id) => {
let var = Local { parent: 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(Variant::from(it).into()),
ValueNs::ImplSelf(impl_id) => PathResolution::SelfType(impl_id.into()),
ValueNs::GenericParam(it) => PathResolution::ConstParam(it.into()),
};
Some(res)
})
};
let items = || {
resolver
.resolve_module_path_in_items(db.upcast(), path.mod_path())
.take_types()
.map(|it| PathResolution::Def(it.into()))
};
let macros = || {
resolver
.resolve_path_as_macro(db.upcast(), path.mod_path())
.map(|def| PathResolution::Macro(def.into()))
};
if prefer_value_ns { values().or_else(types) } else { types().or_else(values) }
.or_else(items)
.or_else(macros)
}
/// Resolves a path where we know it is a qualifier of another path.
///
/// For example, if we have:
/// ```
/// mod my {
/// pub mod foo {
/// struct Bar;
/// }
///
/// pub fn foo() {}
/// }
/// ```
/// then we know that `foo` in `my::foo::Bar` refers to the module, not the function.
fn resolve_hir_path_qualifier(
db: &dyn HirDatabase,
resolver: &Resolver,
path: &Path,
) -> Option<PathResolution> {
let items = resolver
.resolve_module_path_in_items(db.upcast(), path.mod_path())
.take_types()
.map(|it| PathResolution::Def(it.into()));
if items.is_some() {
return items;
}
resolver.resolve_path_in_type_ns_fully(db.upcast(), 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(Variant::from(it).into()),
TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
TypeNs::BuiltinType(it) => PathResolution::Def(BuiltinType::from(it).into()),
TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
})
}