1 files changed, 755 insertions, 0 deletions

diff --git a/crates/ide_completion/src/completions/unqualified_path.rs b/crates/ide_completion/src/completions/unqualified_path.rs
new file mode 100644
index 000000000..e9d0ff665
--- /dev/null
+++ b/crates/ide_completion/src/completions/unqualified_path.rs
@@ -0,0 +1,755 @@
+//! Completion of names from the current scope, e.g. locals and imported items.
+
+use hir::ScopeDef;
+use syntax::AstNode;
+use test_utils::mark;
+
+use crate::{CompletionContext, Completions};
+
+pub(crate) fn complete_unqualified_path(acc: &mut Completions, ctx: &CompletionContext) {
+    if !(ctx.is_trivial_path || ctx.is_pat_binding_or_const) {
+        return;
+    }
+    if ctx.record_lit_syntax.is_some()
+        || ctx.record_pat_syntax.is_some()
+        || ctx.attribute_under_caret.is_some()
+        || ctx.mod_declaration_under_caret.is_some()
+    {
+        return;
+    }
+
+    if let Some(ty) = &ctx.expected_type {
+        super::complete_enum_variants(acc, ctx, ty, |acc, ctx, variant, path| {
+            acc.add_qualified_enum_variant(ctx, variant, path)
+        });
+    }
+
+    if ctx.is_pat_binding_or_const {
+        return;
+    }
+
+    ctx.scope.process_all_names(&mut |name, res| {
+        if let ScopeDef::GenericParam(hir::GenericParam::LifetimeParam(_)) = res {
+            mark::hit!(skip_lifetime_completion);
+            return;
+        }
+        if ctx.use_item_syntax.is_some() {
+            if let (ScopeDef::Unknown, Some(name_ref)) = (&res, &ctx.name_ref_syntax) {
+                if name_ref.syntax().text() == name.to_string().as_str() {
+                    mark::hit!(self_fulfilling_completion);
+                    return;
+                }
+            }
+        }
+        acc.add_resolution(ctx, name.to_string(), &res);
+    });
+}
+
+#[cfg(test)]
+mod tests {
+    use expect_test::{expect, Expect};
+    use test_utils::mark;
+
+    use crate::{
+        test_utils::{check_edit, completion_list_with_config, TEST_CONFIG},
+        CompletionConfig, CompletionKind,
+    };
+
+    fn check(ra_fixture: &str, expect: Expect) {
+        check_with_config(TEST_CONFIG, ra_fixture, expect);
+    }
+
+    fn check_with_config(config: CompletionConfig, ra_fixture: &str, expect: Expect) {
+        let actual = completion_list_with_config(config, ra_fixture, CompletionKind::Reference);
+        expect.assert_eq(&actual)
+    }
+
+    #[test]
+    fn self_fulfilling_completion() {
+        mark::check!(self_fulfilling_completion);
+        check(
+            r#"
+use foo$0
+use std::collections;
+"#,
+            expect![[r#"
+                ?? collections
+            "#]],
+        );
+    }
+
+    #[test]
+    fn bind_pat_and_path_ignore_at() {
+        check(
+            r#"
+enum Enum { A, B }
+fn quux(x: Option<Enum>) {
+    match x {
+        None => (),
+        Some(en$0 @ Enum::A) => (),
+    }
+}
+"#,
+            expect![[""]],
+        );
+    }
+
+    #[test]
+    fn bind_pat_and_path_ignore_ref() {
+        check(
+            r#"
+enum Enum { A, B }
+fn quux(x: Option<Enum>) {
+    match x {
+        None => (),
+        Some(ref en$0) => (),
+    }
+}
+"#,
+            expect![[""]],
+        );
+    }
+
+    #[test]
+    fn bind_pat_and_path() {
+        check(
+            r#"
+enum Enum { A, B }
+fn quux(x: Option<Enum>) {
+    match x {
+        None => (),
+        Some(En$0) => (),
+    }
+}
+"#,
+            expect![[r#"
+                en Enum
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_bindings_from_let() {
+        check(
+            r#"
+fn quux(x: i32) {
+    let y = 92;
+    1 + $0;
+    let z = ();
+}
+"#,
+            expect![[r#"
+                lc y       i32
+                lc x       i32
+                fn quux(…) -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_bindings_from_if_let() {
+        check(
+            r#"
+fn quux() {
+    if let Some(x) = foo() {
+        let y = 92;
+    };
+    if let Some(a) = bar() {
+        let b = 62;
+        1 + $0
+    }
+}
+"#,
+            expect![[r#"
+                lc b      i32
+                lc a
+                fn quux() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_bindings_from_for() {
+        check(
+            r#"
+fn quux() {
+    for x in &[1, 2, 3] { $0 }
+}
+"#,
+            expect![[r#"
+                lc x
+                fn quux() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_if_prefix_is_keyword() {
+        mark::check!(completes_if_prefix_is_keyword);
+        check_edit(
+            "wherewolf",
+            r#"
+fn main() {
+    let wherewolf = 92;
+    drop(where$0)
+}
+"#,
+            r#"
+fn main() {
+    let wherewolf = 92;
+    drop(wherewolf)
+}
+"#,
+        )
+    }
+
+    #[test]
+    fn completes_generic_params() {
+        check(
+            r#"fn quux<T>() { $0 }"#,
+            expect![[r#"
+                tp T
+                fn quux() -> ()
+            "#]],
+        );
+        check(
+            r#"fn quux<const C: usize>() { $0 }"#,
+            expect![[r#"
+                cp C
+                fn quux() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn does_not_complete_lifetimes() {
+        mark::check!(skip_lifetime_completion);
+        check(
+            r#"fn quux<'a>() { $0 }"#,
+            expect![[r#"
+                fn quux() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_generic_params_in_struct() {
+        check(
+            r#"struct S<T> { x: $0}"#,
+            expect![[r#"
+                sp Self
+                tp T
+                st S<…>
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_self_in_enum() {
+        check(
+            r#"enum X { Y($0) }"#,
+            expect![[r#"
+                sp Self
+                en X
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_module_items() {
+        check(
+            r#"
+struct S;
+enum E {}
+fn quux() { $0 }
+"#,
+            expect![[r#"
+                st S
+                fn quux() -> ()
+                en E
+            "#]],
+        );
+    }
+
+    /// Regression test for issue #6091.
+    #[test]
+    fn correctly_completes_module_items_prefixed_with_underscore() {
+        check_edit(
+            "_alpha",
+            r#"
+fn main() {
+    _$0
+}
+fn _alpha() {}
+"#,
+            r#"
+fn main() {
+    _alpha()$0
+}
+fn _alpha() {}
+"#,
+        )
+    }
+
+    #[test]
+    fn completes_extern_prelude() {
+        check(
+            r#"
+//- /lib.rs crate:main deps:other_crate
+use $0;
+
+//- /other_crate/lib.rs crate:other_crate
+// nothing here
+"#,
+            expect![[r#"
+                md other_crate
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_module_items_in_nested_modules() {
+        check(
+            r#"
+struct Foo;
+mod m {
+    struct Bar;
+    fn quux() { $0 }
+}
+"#,
+            expect![[r#"
+                fn quux() -> ()
+                st Bar
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_return_type() {
+        check(
+            r#"
+struct Foo;
+fn x() -> $0
+"#,
+            expect![[r#"
+                st Foo
+                fn x() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn dont_show_both_completions_for_shadowing() {
+        check(
+            r#"
+fn foo() {
+    let bar = 92;
+    {
+        let bar = 62;
+        drop($0)
+    }
+}
+"#,
+            // FIXME: should be only one bar here
+            expect![[r#"
+                lc bar   i32
+                lc bar   i32
+                fn foo() -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_self_in_methods() {
+        check(
+            r#"impl S { fn foo(&self) { $0 } }"#,
+            expect![[r#"
+                lc self &{unknown}
+                sp Self
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_prelude() {
+        check(
+            r#"
+//- /main.rs crate:main deps:std
+fn foo() { let x: $0 }
+
+//- /std/lib.rs crate:std
+#[prelude_import]
+use prelude::*;
+
+mod prelude { struct Option; }
+"#,
+            expect![[r#"
+                fn foo()  -> ()
+                md std
+                st Option
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_prelude_macros() {
+        check(
+            r#"
+//- /main.rs crate:main deps:std
+fn f() {$0}
+
+//- /std/lib.rs crate:std
+#[prelude_import]
+pub use prelude::*;
+
+#[macro_use]
+mod prelude {
+    pub use crate::concat;
+}
+
+mod macros {
+    #[rustc_builtin_macro]
+    #[macro_export]
+    macro_rules! concat { }
+}
+"#,
+            expect![[r##"
+                fn f()        -> ()
+                ma concat!(…) #[macro_export] macro_rules! concat
+                md std
+            "##]],
+        );
+    }
+
+    #[test]
+    fn completes_std_prelude_if_core_is_defined() {
+        check(
+            r#"
+//- /main.rs crate:main deps:core,std
+fn foo() { let x: $0 }
+
+//- /core/lib.rs crate:core
+#[prelude_import]
+use prelude::*;
+
+mod prelude { struct Option; }
+
+//- /std/lib.rs crate:std deps:core
+#[prelude_import]
+use prelude::*;
+
+mod prelude { struct String; }
+"#,
+            expect![[r#"
+                fn foo()  -> ()
+                md std
+                md core
+                st String
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_macros_as_value() {
+        check(
+            r#"
+macro_rules! foo { () => {} }
+
+#[macro_use]
+mod m1 {
+    macro_rules! bar { () => {} }
+}
+
+mod m2 {
+    macro_rules! nope { () => {} }
+
+    #[macro_export]
+    macro_rules! baz { () => {} }
+}
+
+fn main() { let v = $0 }
+"#,
+            expect![[r##"
+                md m1
+                ma baz!(…) #[macro_export] macro_rules! baz
+                fn main()  -> ()
+                md m2
+                ma bar!(…) macro_rules! bar
+                ma foo!(…) macro_rules! foo
+            "##]],
+        );
+    }
+
+    #[test]
+    fn completes_both_macro_and_value() {
+        check(
+            r#"
+macro_rules! foo { () => {} }
+fn foo() { $0 }
+"#,
+            expect![[r#"
+                fn foo()   -> ()
+                ma foo!(…) macro_rules! foo
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_macros_as_type() {
+        check(
+            r#"
+macro_rules! foo { () => {} }
+fn main() { let x: $0 }
+"#,
+            expect![[r#"
+                fn main()  -> ()
+                ma foo!(…) macro_rules! foo
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_macros_as_stmt() {
+        check(
+            r#"
+macro_rules! foo { () => {} }
+fn main() { $0 }
+"#,
+            expect![[r#"
+                fn main()  -> ()
+                ma foo!(…) macro_rules! foo
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_local_item() {
+        check(
+            r#"
+fn main() {
+    return f$0;
+    fn frobnicate() {}
+}
+"#,
+            expect![[r#"
+                fn frobnicate() -> ()
+                fn main()       -> ()
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_in_simple_macro_1() {
+        check(
+            r#"
+macro_rules! m { ($e:expr) => { $e } }
+fn quux(x: i32) {
+    let y = 92;
+    m!($0);
+}
+"#,
+            expect![[r#"
+                lc y       i32
+                lc x       i32
+                fn quux(…) -> ()
+                ma m!(…)   macro_rules! m
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_in_simple_macro_2() {
+        check(
+            r"
+macro_rules! m { ($e:expr) => { $e } }
+fn quux(x: i32) {
+    let y = 92;
+    m!(x$0);
+}
+",
+            expect![[r#"
+                lc y       i32
+                lc x       i32
+                fn quux(…) -> ()
+                ma m!(…)   macro_rules! m
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_in_simple_macro_without_closing_parens() {
+        check(
+            r#"
+macro_rules! m { ($e:expr) => { $e } }
+fn quux(x: i32) {
+    let y = 92;
+    m!(x$0
+}
+"#,
+            expect![[r#"
+                lc y       i32
+                lc x       i32
+                fn quux(…) -> ()
+                ma m!(…)   macro_rules! m
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_unresolved_uses() {
+        check(
+            r#"
+use spam::Quux;
+
+fn main() { $0 }
+"#,
+            expect![[r#"
+                fn main() -> ()
+                ?? Quux
+            "#]],
+        );
+    }
+
+    #[test]
+    fn completes_enum_variant_matcharm() {
+        check(
+            r#"
+enum Foo { Bar, Baz, Quux }
+
+fn main() {
+    let foo = Foo::Quux;
+    match foo { Qu$0 }
+}
+"#,
+            expect![[r#"
+                ev Foo::Bar  ()
+                ev Foo::Baz  ()
+                ev Foo::Quux ()
+                en Foo
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_enum_variant_matcharm_ref() {
+        check(
+            r#"
+enum Foo { Bar, Baz, Quux }
+
+fn main() {
+    let foo = Foo::Quux;
+    match &foo { Qu$0 }
+}
+"#,
+            expect![[r#"
+                ev Foo::Bar  ()
+                ev Foo::Baz  ()
+                ev Foo::Quux ()
+                en Foo
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_enum_variant_iflet() {
+        check(
+            r#"
+enum Foo { Bar, Baz, Quux }
+
+fn main() {
+    let foo = Foo::Quux;
+    if let Qu$0 = foo { }
+}
+"#,
+            expect![[r#"
+                ev Foo::Bar  ()
+                ev Foo::Baz  ()
+                ev Foo::Quux ()
+                en Foo
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_enum_variant_basic_expr() {
+        check(
+            r#"
+enum Foo { Bar, Baz, Quux }
+fn main() { let foo: Foo = Q$0 }
+"#,
+            expect![[r#"
+                ev Foo::Bar  ()
+                ev Foo::Baz  ()
+                ev Foo::Quux ()
+                en Foo
+                fn main()    -> ()
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_enum_variant_from_module() {
+        check(
+            r#"
+mod m { pub enum E { V } }
+fn f() -> m::E { V$0 }
+"#,
+            expect![[r#"
+                ev m::E::V ()
+                md m
+                fn f()     -> E
+            "#]],
+        )
+    }
+
+    #[test]
+    fn completes_enum_variant_impl() {
+        check(
+            r#"
+enum Foo { Bar, Baz, Quux }
+impl Foo {
+    fn foo() { match Foo::Bar { Q$0 } }
+}
+"#,
+            expect![[r#"
+                ev Self::Bar  ()
+                ev Self::Baz  ()
+                ev Self::Quux ()
+                ev Foo::Bar   ()
+                ev Foo::Baz   ()
+                ev Foo::Quux  ()
+                sp Self
+                en Foo
+            "#]],
+        )
+    }
+
+    #[test]
+    fn dont_complete_attr() {
+        check(
+            r#"
+struct Foo;
+#[$0]
+fn f() {}
+"#,
+            expect![[""]],
+        )
+    }
+
+    #[test]
+    fn completes_type_or_trait_in_impl_block() {
+        check(
+            r#"
+trait MyTrait {}
+struct MyStruct {}
+
+impl My$0
+"#,
+            expect![[r#"
+                sp Self
+                tt MyTrait
+                st MyStruct
+            "#]],
+        )
+    }
+}