mirror of
https://github.com/rust-lang/rust-analyzer.git
synced 2025-09-27 04:19:13 +00:00
481 lines
14 KiB
Rust
481 lines
14 KiB
Rust
use std::sync::Arc;
|
|
|
|
use rustc_hash::{FxHashMap, FxHashSet};
|
|
|
|
use ra_syntax::{
|
|
AstNode, SyntaxNode, TextUnit, TextRange,
|
|
algo::generate,
|
|
ast,
|
|
};
|
|
use ra_arena::{Arena, RawId, impl_arena_id};
|
|
use ra_db::LocalSyntaxPtr;
|
|
|
|
use crate::{Name, AsName, expr::{PatId, ExprId, Pat, Expr, Body, Statement, BodySyntaxMapping}};
|
|
|
|
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
|
|
pub struct ScopeId(RawId);
|
|
impl_arena_id!(ScopeId);
|
|
|
|
#[derive(Debug, PartialEq, Eq)]
|
|
pub struct FnScopes {
|
|
body: Arc<Body>,
|
|
scopes: Arena<ScopeId, ScopeData>,
|
|
scope_for: FxHashMap<ExprId, ScopeId>,
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Eq)]
|
|
pub struct ScopeEntry {
|
|
name: Name,
|
|
pat: PatId,
|
|
}
|
|
|
|
#[derive(Debug, PartialEq, Eq)]
|
|
pub struct ScopeData {
|
|
parent: Option<ScopeId>,
|
|
entries: Vec<ScopeEntry>,
|
|
}
|
|
|
|
impl FnScopes {
|
|
pub(crate) fn new(body: Arc<Body>) -> FnScopes {
|
|
let mut scopes = FnScopes {
|
|
body: body.clone(),
|
|
scopes: Arena::default(),
|
|
scope_for: FxHashMap::default(),
|
|
};
|
|
let root = scopes.root_scope();
|
|
scopes.add_params_bindings(root, body.args());
|
|
compute_expr_scopes(body.body_expr(), &body, &mut scopes, root);
|
|
scopes
|
|
}
|
|
pub fn entries(&self, scope: ScopeId) -> &[ScopeEntry] {
|
|
&self.scopes[scope].entries
|
|
}
|
|
pub fn scope_chain_for<'a>(&'a self, expr: ExprId) -> impl Iterator<Item = ScopeId> + 'a {
|
|
generate(self.scope_for(expr), move |&scope| {
|
|
self.scopes[scope].parent
|
|
})
|
|
}
|
|
|
|
pub fn resolve_local_name<'a>(
|
|
&'a self,
|
|
context_expr: ExprId,
|
|
name: Name,
|
|
) -> Option<&'a ScopeEntry> {
|
|
let mut shadowed = FxHashSet::default();
|
|
let ret = self
|
|
.scope_chain_for(context_expr)
|
|
.flat_map(|scope| self.entries(scope).iter())
|
|
.filter(|entry| shadowed.insert(entry.name()))
|
|
.find(|entry| entry.name() == &name);
|
|
ret
|
|
}
|
|
|
|
fn root_scope(&mut self) -> ScopeId {
|
|
self.scopes.alloc(ScopeData {
|
|
parent: None,
|
|
entries: vec![],
|
|
})
|
|
}
|
|
fn new_scope(&mut self, parent: ScopeId) -> ScopeId {
|
|
self.scopes.alloc(ScopeData {
|
|
parent: Some(parent),
|
|
entries: vec![],
|
|
})
|
|
}
|
|
fn add_bindings(&mut self, body: &Body, scope: ScopeId, pat: PatId) {
|
|
match &body[pat] {
|
|
Pat::Bind { name } => self.scopes[scope].entries.push(ScopeEntry {
|
|
name: name.clone(),
|
|
pat,
|
|
}),
|
|
p => p.walk_child_pats(|pat| self.add_bindings(body, scope, pat)),
|
|
}
|
|
}
|
|
fn add_params_bindings(&mut self, scope: ScopeId, params: &[PatId]) {
|
|
let body = Arc::clone(&self.body);
|
|
params
|
|
.into_iter()
|
|
.for_each(|pat| self.add_bindings(&body, scope, *pat));
|
|
}
|
|
fn set_scope(&mut self, node: ExprId, scope: ScopeId) {
|
|
self.scope_for.insert(node, scope);
|
|
}
|
|
fn scope_for(&self, expr: ExprId) -> Option<ScopeId> {
|
|
self.scope_for.get(&expr).map(|&scope| scope)
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Clone, PartialEq, Eq)]
|
|
pub struct ScopesWithSyntaxMapping {
|
|
pub syntax_mapping: Arc<BodySyntaxMapping>,
|
|
pub scopes: Arc<FnScopes>,
|
|
}
|
|
|
|
#[derive(Debug, Clone, PartialEq, Eq)]
|
|
pub struct ScopeEntryWithSyntax {
|
|
name: Name,
|
|
ptr: LocalSyntaxPtr,
|
|
}
|
|
|
|
impl ScopeEntryWithSyntax {
|
|
pub fn name(&self) -> &Name {
|
|
&self.name
|
|
}
|
|
pub fn ptr(&self) -> LocalSyntaxPtr {
|
|
self.ptr
|
|
}
|
|
}
|
|
|
|
impl ScopesWithSyntaxMapping {
|
|
pub fn scope_chain<'a>(&'a self, node: &SyntaxNode) -> impl Iterator<Item = ScopeId> + 'a {
|
|
generate(self.scope_for(node), move |&scope| {
|
|
self.scopes.scopes[scope].parent
|
|
})
|
|
}
|
|
pub fn scope_chain_for_offset<'a>(
|
|
&'a self,
|
|
offset: TextUnit,
|
|
) -> impl Iterator<Item = ScopeId> + 'a {
|
|
let scope = self
|
|
.scopes
|
|
.scope_for
|
|
.iter()
|
|
.filter_map(|(id, scope)| Some((self.syntax_mapping.expr_syntax(*id)?, scope)))
|
|
// find containing scope
|
|
.min_by_key(|(ptr, _scope)| {
|
|
(
|
|
!(ptr.range().start() <= offset && offset <= ptr.range().end()),
|
|
ptr.range().len(),
|
|
)
|
|
})
|
|
.map(|(ptr, scope)| self.adjust(ptr, *scope, offset));
|
|
|
|
generate(scope, move |&scope| self.scopes.scopes[scope].parent)
|
|
}
|
|
// XXX: during completion, cursor might be outside of any particular
|
|
// expression. Try to figure out the correct scope...
|
|
fn adjust(&self, ptr: LocalSyntaxPtr, original_scope: ScopeId, offset: TextUnit) -> ScopeId {
|
|
let r = ptr.range();
|
|
let child_scopes = self
|
|
.scopes
|
|
.scope_for
|
|
.iter()
|
|
.filter_map(|(id, scope)| Some((self.syntax_mapping.expr_syntax(*id)?, 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)
|
|
.unwrap_or(original_scope)
|
|
}
|
|
|
|
pub fn resolve_local_name(&self, name_ref: &ast::NameRef) -> Option<ScopeEntryWithSyntax> {
|
|
let mut shadowed = FxHashSet::default();
|
|
let name = name_ref.as_name();
|
|
let ret = self
|
|
.scope_chain(name_ref.syntax())
|
|
.flat_map(|scope| self.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: self.syntax_mapping.pat_syntax(entry.pat())?,
|
|
})
|
|
})
|
|
}
|
|
|
|
pub fn find_all_refs(&self, pat: &ast::BindPat) -> Vec<ReferenceDescriptor> {
|
|
let fn_def = pat.syntax().ancestors().find_map(ast::FnDef::cast).unwrap();
|
|
let name_ptr = LocalSyntaxPtr::new(pat.syntax());
|
|
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() == name_ptr,
|
|
})
|
|
.map(|name_ref| ReferenceDescriptor {
|
|
name: name_ref.syntax().text().to_string(),
|
|
range: name_ref.syntax().range(),
|
|
})
|
|
.collect()
|
|
}
|
|
|
|
fn scope_for(&self, node: &SyntaxNode) -> Option<ScopeId> {
|
|
node.ancestors()
|
|
.map(LocalSyntaxPtr::new)
|
|
.filter_map(|ptr| self.syntax_mapping.syntax_expr(ptr))
|
|
.find_map(|it| self.scopes.scope_for(it))
|
|
}
|
|
}
|
|
|
|
impl ScopeEntry {
|
|
pub fn name(&self) -> &Name {
|
|
&self.name
|
|
}
|
|
pub fn pat(&self) -> PatId {
|
|
self.pat
|
|
}
|
|
}
|
|
|
|
fn compute_block_scopes(
|
|
statements: &[Statement],
|
|
tail: Option<ExprId>,
|
|
body: &Body,
|
|
scopes: &mut FnScopes,
|
|
mut scope: ScopeId,
|
|
) {
|
|
for stmt in statements {
|
|
match stmt {
|
|
Statement::Let {
|
|
pat, initializer, ..
|
|
} => {
|
|
if let Some(expr) = initializer {
|
|
scopes.set_scope(*expr, scope);
|
|
compute_expr_scopes(*expr, body, scopes, scope);
|
|
}
|
|
scope = scopes.new_scope(scope);
|
|
scopes.add_bindings(body, scope, *pat);
|
|
}
|
|
Statement::Expr(expr) => {
|
|
scopes.set_scope(*expr, scope);
|
|
compute_expr_scopes(*expr, body, scopes, scope);
|
|
}
|
|
}
|
|
}
|
|
if let Some(expr) = tail {
|
|
compute_expr_scopes(expr, body, scopes, scope);
|
|
}
|
|
}
|
|
|
|
fn compute_expr_scopes(expr: ExprId, body: &Body, scopes: &mut FnScopes, scope: ScopeId) {
|
|
scopes.set_scope(expr, scope);
|
|
match &body[expr] {
|
|
Expr::Block { statements, tail } => {
|
|
compute_block_scopes(&statements, *tail, body, scopes, scope);
|
|
}
|
|
Expr::For {
|
|
iterable,
|
|
pat,
|
|
body: body_expr,
|
|
} => {
|
|
compute_expr_scopes(*iterable, body, scopes, scope);
|
|
let scope = scopes.new_scope(scope);
|
|
scopes.add_bindings(body, scope, *pat);
|
|
compute_expr_scopes(*body_expr, body, scopes, scope);
|
|
}
|
|
Expr::Lambda {
|
|
args,
|
|
body: body_expr,
|
|
..
|
|
} => {
|
|
let scope = scopes.new_scope(scope);
|
|
scopes.add_params_bindings(scope, &args);
|
|
compute_expr_scopes(*body_expr, body, scopes, scope);
|
|
}
|
|
Expr::Match { expr, arms } => {
|
|
compute_expr_scopes(*expr, body, scopes, scope);
|
|
for arm in arms {
|
|
let scope = scopes.new_scope(scope);
|
|
for pat in &arm.pats {
|
|
scopes.add_bindings(body, scope, *pat);
|
|
}
|
|
scopes.set_scope(arm.expr, scope);
|
|
compute_expr_scopes(arm.expr, body, scopes, scope);
|
|
}
|
|
}
|
|
e => e.walk_child_exprs(|e| compute_expr_scopes(e, body, scopes, scope)),
|
|
};
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
pub struct ReferenceDescriptor {
|
|
pub range: TextRange,
|
|
pub name: String,
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use ra_editor::find_node_at_offset;
|
|
use ra_syntax::SourceFile;
|
|
use test_utils::{extract_offset, assert_eq_text};
|
|
|
|
use crate::expr;
|
|
|
|
use super::*;
|
|
|
|
fn do_check(code: &str, expected: &[&str]) {
|
|
let (off, code) = extract_offset(code);
|
|
let code = {
|
|
let mut buf = String::new();
|
|
let off = u32::from(off) as usize;
|
|
buf.push_str(&code[..off]);
|
|
buf.push_str("marker");
|
|
buf.push_str(&code[off..]);
|
|
buf
|
|
};
|
|
let file = SourceFile::parse(&code);
|
|
let marker: &ast::PathExpr = find_node_at_offset(file.syntax(), off).unwrap();
|
|
let fn_def: &ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
|
|
let body_hir = expr::collect_fn_body_syntax(fn_def);
|
|
let scopes = FnScopes::new(Arc::clone(body_hir.body()));
|
|
let scopes = ScopesWithSyntaxMapping {
|
|
scopes: Arc::new(scopes),
|
|
syntax_mapping: Arc::new(body_hir),
|
|
};
|
|
let actual = scopes
|
|
.scope_chain(marker.syntax())
|
|
.flat_map(|scope| scopes.scopes.entries(scope))
|
|
.map(|it| it.name().to_string())
|
|
.collect::<Vec<_>>()
|
|
.join("\n");
|
|
let expected = expected.join("\n");
|
|
assert_eq_text!(&expected, &actual);
|
|
}
|
|
|
|
#[test]
|
|
fn test_lambda_scope() {
|
|
do_check(
|
|
r"
|
|
fn quux(foo: i32) {
|
|
let f = |bar, baz: i32| {
|
|
<|>
|
|
};
|
|
}",
|
|
&["bar", "baz", "foo"],
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_call_scope() {
|
|
do_check(
|
|
r"
|
|
fn quux() {
|
|
f(|x| <|> );
|
|
}",
|
|
&["x"],
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_method_call_scope() {
|
|
do_check(
|
|
r"
|
|
fn quux() {
|
|
z.f(|x| <|> );
|
|
}",
|
|
&["x"],
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_loop_scope() {
|
|
do_check(
|
|
r"
|
|
fn quux() {
|
|
loop {
|
|
let x = ();
|
|
<|>
|
|
};
|
|
}",
|
|
&["x"],
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_match() {
|
|
do_check(
|
|
r"
|
|
fn quux() {
|
|
match () {
|
|
Some(x) => {
|
|
<|>
|
|
}
|
|
};
|
|
}",
|
|
&["x"],
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_shadow_variable() {
|
|
do_check(
|
|
r"
|
|
fn foo(x: String) {
|
|
let x : &str = &x<|>;
|
|
}",
|
|
&["x"],
|
|
);
|
|
}
|
|
|
|
fn do_check_local_name(code: &str, expected_offset: u32) {
|
|
let (off, code) = extract_offset(code);
|
|
let file = SourceFile::parse(&code);
|
|
let fn_def: &ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
|
|
let name_ref: &ast::NameRef = find_node_at_offset(file.syntax(), off).unwrap();
|
|
|
|
let body_hir = expr::collect_fn_body_syntax(fn_def);
|
|
let scopes = FnScopes::new(Arc::clone(body_hir.body()));
|
|
let scopes = ScopesWithSyntaxMapping {
|
|
scopes: Arc::new(scopes),
|
|
syntax_mapping: Arc::new(body_hir),
|
|
};
|
|
|
|
let local_name_entry = scopes.resolve_local_name(name_ref).unwrap();
|
|
let local_name = local_name_entry.ptr();
|
|
let expected_name =
|
|
find_node_at_offset::<ast::Name>(file.syntax(), expected_offset.into()).unwrap();
|
|
assert_eq!(local_name.range(), expected_name.syntax().range());
|
|
}
|
|
|
|
#[test]
|
|
fn test_resolve_local_name() {
|
|
do_check_local_name(
|
|
r#"
|
|
fn foo(x: i32, y: u32) {
|
|
{
|
|
let z = x * 2;
|
|
}
|
|
{
|
|
let t = x<|> * 3;
|
|
}
|
|
}"#,
|
|
21,
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_resolve_local_name_declaration() {
|
|
do_check_local_name(
|
|
r#"
|
|
fn foo(x: String) {
|
|
let x : &str = &x<|>;
|
|
}"#,
|
|
21,
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn test_resolve_local_name_shadow() {
|
|
do_check_local_name(
|
|
r"
|
|
fn foo(x: String) {
|
|
let x : &str = &x;
|
|
x<|>
|
|
}",
|
|
46,
|
|
);
|
|
}
|
|
}
|