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|
use rustc_hash::FxHashSet;
use ra_syntax::{
SourceFileNode, AstNode,
ast,
SyntaxKind::*,
};
use hir::{
self,
FnScopes, Path
};
use crate::{
db::RootDatabase,
completion::{CompletionItem, Completions, CompletionKind::*},
Cancelable
};
pub(super) fn completions(
acc: &mut Completions,
db: &RootDatabase,
module: &hir::Module,
_file: &SourceFileNode,
name_ref: ast::NameRef,
) -> Cancelable<()> {
let kind = match classify_name_ref(name_ref) {
Some(it) => it,
None => return Ok(()),
};
match kind {
NameRefKind::LocalRef { enclosing_fn } => {
if let Some(fn_def) = enclosing_fn {
let scopes = FnScopes::new(fn_def);
complete_fn(name_ref, &scopes, acc);
}
let module_scope = module.scope(db)?;
module_scope
.entries()
.filter(|(_name, res)| {
// Don't expose this item
match res.import {
None => true,
Some(import) => {
let range = import.range(db, module.source().file_id());
!range.is_subrange(&name_ref.syntax().range())
}
}
})
.for_each(|(name, _res)| {
CompletionItem::new(name.to_string())
.kind(Reference)
.add_to(acc)
});
}
NameRefKind::Path(_) => (),
NameRefKind::BareIdentInMod => (),
}
Ok(())
}
enum NameRefKind<'a> {
/// NameRef is a part of single-segment path, for example, a refernece to a
/// local variable.
LocalRef {
enclosing_fn: Option<ast::FnDef<'a>>,
},
/// NameRef is the last segment in some path
Path(Path),
/// NameRef is bare identifier at the module's root.
/// Used for keyword completion
BareIdentInMod,
}
fn classify_name_ref(name_ref: ast::NameRef) -> Option<NameRefKind> {
let name_range = name_ref.syntax().range();
let top_node = name_ref
.syntax()
.ancestors()
.take_while(|it| it.range() == name_range)
.last()
.unwrap();
match top_node.parent().map(|it| it.kind()) {
Some(SOURCE_FILE) | Some(ITEM_LIST) => return Some(NameRefKind::BareIdentInMod),
_ => (),
}
let parent = name_ref.syntax().parent()?;
if let Some(segment) = ast::PathSegment::cast(parent) {
let path = segment.parent_path();
if let Some(path) = Path::from_ast(path) {
if !path.is_ident() {
return Some(NameRefKind::Path(path));
}
}
if path.qualifier().is_none() {
let enclosing_fn = name_ref
.syntax()
.ancestors()
.take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
.find_map(ast::FnDef::cast);
return Some(NameRefKind::LocalRef { enclosing_fn });
}
}
None
}
fn complete_fn(name_ref: ast::NameRef, scopes: &FnScopes, acc: &mut Completions) {
let mut shadowed = FxHashSet::default();
scopes
.scope_chain(name_ref.syntax())
.flat_map(|scope| scopes.entries(scope).iter())
.filter(|entry| shadowed.insert(entry.name()))
.for_each(|entry| {
CompletionItem::new(entry.name().to_string())
.kind(Reference)
.add_to(acc)
});
if scopes.self_param.is_some() {
CompletionItem::new("self").kind(Reference).add_to(acc);
}
}
#[cfg(test)]
mod tests {
use crate::completion::{CompletionKind, check_completion};
fn check_reference_completion(code: &str, expected_completions: &str) {
check_completion(code, expected_completions, CompletionKind::Reference);
}
#[test]
fn test_completion_let_scope() {
check_reference_completion(
r"
fn quux(x: i32) {
let y = 92;
1 + <|>;
let z = ();
}
",
"y;x;quux",
);
}
#[test]
fn test_completion_if_let_scope() {
check_reference_completion(
r"
fn quux() {
if let Some(x) = foo() {
let y = 92;
};
if let Some(a) = bar() {
let b = 62;
1 + <|>
}
}
",
"b;a;quux",
);
}
#[test]
fn test_completion_for_scope() {
check_reference_completion(
r"
fn quux() {
for x in &[1, 2, 3] {
<|>
}
}
",
"x;quux",
);
}
#[test]
fn test_completion_mod_scope() {
check_reference_completion(
r"
struct Foo;
enum Baz {}
fn quux() {
<|>
}
",
"quux;Foo;Baz",
);
}
#[test]
fn test_completion_mod_scope_no_self_use() {
check_reference_completion(
r"
use foo<|>;
",
"",
);
}
#[test]
fn test_completion_self_path() {
check_reference_completion(
r"
use self::m::<|>;
mod m {
struct Bar;
}
",
"Bar",
);
}
#[test]
fn test_completion_mod_scope_nested() {
check_reference_completion(
r"
struct Foo;
mod m {
struct Bar;
fn quux() { <|> }
}
",
"quux;Bar",
);
}
#[test]
fn test_complete_type() {
check_reference_completion(
r"
struct Foo;
fn x() -> <|>
",
"Foo;x",
)
}
#[test]
fn test_complete_shadowing() {
check_reference_completion(
r"
fn foo() -> {
let bar = 92;
{
let bar = 62;
<|>
}
}
",
"bar;foo",
)
}
#[test]
fn test_complete_self() {
check_reference_completion(r"impl S { fn foo(&self) { <|> } }", "self")
}
#[test]
fn test_complete_crate_path() {
check_reference_completion(
"
//- /lib.rs
mod foo;
struct Spam;
//- /foo.rs
use crate::Sp<|>
",
"Spam;foo",
);
}
#[test]
fn test_complete_crate_path_with_braces() {
check_reference_completion(
"
//- /lib.rs
mod foo;
struct Spam;
//- /foo.rs
use crate::{Sp<|>};
",
"Spam;foo",
);
}
#[test]
fn test_complete_crate_path_in_nested_tree() {
check_reference_completion(
"
//- /lib.rs
mod foo;
pub mod bar {
pub mod baz {
pub struct Spam;
}
}
//- /foo.rs
use crate::{bar::{baz::Sp<|>}};
",
"Spam",
);
}
}
|
