1 files changed, 696 insertions, 0 deletions

diff --git a/crates/ide/src/references.rs b/crates/ide/src/references.rs
new file mode 100644
index 000000000..722c8f406
--- /dev/null
+++ b/crates/ide/src/references.rs
@@ -0,0 +1,696 @@
+//! This module implements a reference search.
+//! First, the element at the cursor position must be either an `ast::Name`
+//! or `ast::NameRef`. If it's a `ast::NameRef`, at the classification step we
+//! try to resolve the direct tree parent of this element, otherwise we
+//! already have a definition and just need to get its HIR together with
+//! some information that is needed for futher steps of searching.
+//! After that, we collect files that might contain references and look
+//! for text occurrences of the identifier. If there's an `ast::NameRef`
+//! at the index that the match starts at and its tree parent is
+//! resolved to the search element definition, we get a reference.
+
+mod rename;
+
+use hir::Semantics;
+use ide_db::{
+    defs::{classify_name, classify_name_ref, Definition},
+    search::SearchScope,
+    RootDatabase,
+};
+use syntax::{
+    algo::find_node_at_offset,
+    ast::{self, NameOwner},
+    AstNode, SyntaxKind, SyntaxNode, TextRange, TokenAtOffset,
+};
+
+use crate::{display::TryToNav, FilePosition, FileRange, NavigationTarget, RangeInfo};
+
+pub(crate) use self::rename::rename;
+
+pub use ide_db::search::{Reference, ReferenceAccess, ReferenceKind};
+
+#[derive(Debug, Clone)]
+pub struct ReferenceSearchResult {
+    declaration: Declaration,
+    references: Vec<Reference>,
+}
+
+#[derive(Debug, Clone)]
+pub struct Declaration {
+    pub nav: NavigationTarget,
+    pub kind: ReferenceKind,
+    pub access: Option<ReferenceAccess>,
+}
+
+impl ReferenceSearchResult {
+    pub fn declaration(&self) -> &Declaration {
+        &self.declaration
+    }
+
+    pub fn decl_target(&self) -> &NavigationTarget {
+        &self.declaration.nav
+    }
+
+    pub fn references(&self) -> &[Reference] {
+        &self.references
+    }
+
+    /// Total number of references
+    /// At least 1 since all valid references should
+    /// Have a declaration
+    pub fn len(&self) -> usize {
+        self.references.len() + 1
+    }
+}
+
+// allow turning ReferenceSearchResult into an iterator
+// over References
+impl IntoIterator for ReferenceSearchResult {
+    type Item = Reference;
+    type IntoIter = std::vec::IntoIter<Reference>;
+
+    fn into_iter(mut self) -> Self::IntoIter {
+        let mut v = Vec::with_capacity(self.len());
+        v.push(Reference {
+            file_range: FileRange {
+                file_id: self.declaration.nav.file_id,
+                range: self.declaration.nav.focus_or_full_range(),
+            },
+            kind: self.declaration.kind,
+            access: self.declaration.access,
+        });
+        v.append(&mut self.references);
+        v.into_iter()
+    }
+}
+
+pub(crate) fn find_all_refs(
+    sema: &Semantics<RootDatabase>,
+    position: FilePosition,
+    search_scope: Option<SearchScope>,
+) -> Option<RangeInfo<ReferenceSearchResult>> {
+    let _p = profile::span("find_all_refs");
+    let syntax = sema.parse(position.file_id).syntax().clone();
+
+    let (opt_name, search_kind) = if let Some(name) =
+        get_struct_def_name_for_struct_literal_search(&sema, &syntax, position)
+    {
+        (Some(name), ReferenceKind::StructLiteral)
+    } else {
+        (
+            sema.find_node_at_offset_with_descend::<ast::Name>(&syntax, position.offset),
+            ReferenceKind::Other,
+        )
+    };
+
+    let RangeInfo { range, info: def } = find_name(&sema, &syntax, position, opt_name)?;
+
+    let references = def
+        .usages(sema)
+        .set_scope(search_scope)
+        .all()
+        .into_iter()
+        .filter(|r| search_kind == ReferenceKind::Other || search_kind == r.kind)
+        .collect();
+
+    let decl_range = def.try_to_nav(sema.db)?.focus_or_full_range();
+
+    let declaration = Declaration {
+        nav: def.try_to_nav(sema.db)?,
+        kind: ReferenceKind::Other,
+        access: decl_access(&def, &syntax, decl_range),
+    };
+
+    Some(RangeInfo::new(range, ReferenceSearchResult { declaration, references }))
+}
+
+fn find_name(
+    sema: &Semantics<RootDatabase>,
+    syntax: &SyntaxNode,
+    position: FilePosition,
+    opt_name: Option<ast::Name>,
+) -> Option<RangeInfo<Definition>> {
+    if let Some(name) = opt_name {
+        let def = classify_name(sema, &name)?.definition(sema.db);
+        let range = name.syntax().text_range();
+        return Some(RangeInfo::new(range, def));
+    }
+    let name_ref =
+        sema.find_node_at_offset_with_descend::<ast::NameRef>(&syntax, position.offset)?;
+    let def = classify_name_ref(sema, &name_ref)?.definition(sema.db);
+    let range = name_ref.syntax().text_range();
+    Some(RangeInfo::new(range, def))
+}
+
+fn decl_access(def: &Definition, syntax: &SyntaxNode, range: TextRange) -> Option<ReferenceAccess> {
+    match def {
+        Definition::Local(_) | Definition::Field(_) => {}
+        _ => return None,
+    };
+
+    let stmt = find_node_at_offset::<ast::LetStmt>(syntax, range.start())?;
+    if stmt.initializer().is_some() {
+        let pat = stmt.pat()?;
+        if let ast::Pat::IdentPat(it) = pat {
+            if it.mut_token().is_some() {
+                return Some(ReferenceAccess::Write);
+            }
+        }
+    }
+
+    None
+}
+
+fn get_struct_def_name_for_struct_literal_search(
+    sema: &Semantics<RootDatabase>,
+    syntax: &SyntaxNode,
+    position: FilePosition,
+) -> Option<ast::Name> {
+    if let TokenAtOffset::Between(ref left, ref right) = syntax.token_at_offset(position.offset) {
+        if right.kind() != SyntaxKind::L_CURLY && right.kind() != SyntaxKind::L_PAREN {
+            return None;
+        }
+        if let Some(name) =
+            sema.find_node_at_offset_with_descend::<ast::Name>(&syntax, left.text_range().start())
+        {
+            return name.syntax().ancestors().find_map(ast::Struct::cast).and_then(|l| l.name());
+        }
+        if sema
+            .find_node_at_offset_with_descend::<ast::GenericParamList>(
+                &syntax,
+                left.text_range().start(),
+            )
+            .is_some()
+        {
+            return left.ancestors().find_map(ast::Struct::cast).and_then(|l| l.name());
+        }
+    }
+    None
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        mock_analysis::{analysis_and_position, MockAnalysis},
+        Declaration, Reference, ReferenceSearchResult, SearchScope,
+    };
+
+    #[test]
+    fn test_struct_literal_after_space() {
+        let refs = get_all_refs(
+            r#"
+struct Foo <|>{
+    a: i32,
+}
+impl Foo {
+    fn f() -> i32 { 42 }
+}
+fn main() {
+    let f: Foo;
+    f = Foo {a: Foo::f()};
+}
+"#,
+        );
+        check_result(
+            refs,
+            "Foo STRUCT FileId(1) 0..26 7..10 Other",
+            &["FileId(1) 101..104 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_struct_literal_before_space() {
+        let refs = get_all_refs(
+            r#"
+struct Foo<|> {}
+    fn main() {
+    let f: Foo;
+    f = Foo {};
+}
+"#,
+        );
+        check_result(
+            refs,
+            "Foo STRUCT FileId(1) 0..13 7..10 Other",
+            &["FileId(1) 41..44 Other", "FileId(1) 54..57 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_struct_literal_with_generic_type() {
+        let refs = get_all_refs(
+            r#"
+struct Foo<T> <|>{}
+    fn main() {
+    let f: Foo::<i32>;
+    f = Foo {};
+}
+"#,
+        );
+        check_result(
+            refs,
+            "Foo STRUCT FileId(1) 0..16 7..10 Other",
+            &["FileId(1) 64..67 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_struct_literal_for_tuple() {
+        let refs = get_all_refs(
+            r#"
+struct Foo<|>(i32);
+
+fn main() {
+    let f: Foo;
+    f = Foo(1);
+}
+"#,
+        );
+        check_result(
+            refs,
+            "Foo STRUCT FileId(1) 0..16 7..10 Other",
+            &["FileId(1) 54..57 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_for_local() {
+        let refs = get_all_refs(
+            r#"
+fn main() {
+    let mut i = 1;
+    let j = 1;
+    i = i<|> + j;
+
+    {
+        i = 0;
+    }
+
+    i = 5;
+}"#,
+        );
+        check_result(
+            refs,
+            "i IDENT_PAT FileId(1) 24..25 Other Write",
+            &[
+                "FileId(1) 50..51 Other Write",
+                "FileId(1) 54..55 Other Read",
+                "FileId(1) 76..77 Other Write",
+                "FileId(1) 94..95 Other Write",
+            ],
+        );
+    }
+
+    #[test]
+    fn search_filters_by_range() {
+        let refs = get_all_refs(
+            r#"
+fn foo() {
+    let spam<|> = 92;
+    spam + spam
+}
+fn bar() {
+    let spam = 92;
+    spam + spam
+}
+"#,
+        );
+        check_result(
+            refs,
+            "spam IDENT_PAT FileId(1) 19..23 Other",
+            &["FileId(1) 34..38 Other Read", "FileId(1) 41..45 Other Read"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_for_param_inside() {
+        let refs = get_all_refs(
+            r#"
+fn foo(i : u32) -> u32 {
+    i<|>
+}
+"#,
+        );
+        check_result(refs, "i IDENT_PAT FileId(1) 7..8 Other", &["FileId(1) 29..30 Other Read"]);
+    }
+
+    #[test]
+    fn test_find_all_refs_for_fn_param() {
+        let refs = get_all_refs(
+            r#"
+fn foo(i<|> : u32) -> u32 {
+    i
+}
+"#,
+        );
+        check_result(refs, "i IDENT_PAT FileId(1) 7..8 Other", &["FileId(1) 29..30 Other Read"]);
+    }
+
+    #[test]
+    fn test_find_all_refs_field_name() {
+        let refs = get_all_refs(
+            r#"
+//- /lib.rs
+struct Foo {
+    pub spam<|>: u32,
+}
+
+fn main(s: Foo) {
+    let f = s.spam;
+}
+"#,
+        );
+        check_result(
+            refs,
+            "spam RECORD_FIELD FileId(1) 17..30 21..25 Other",
+            &["FileId(1) 67..71 Other Read"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_impl_item_name() {
+        let refs = get_all_refs(
+            r#"
+struct Foo;
+impl Foo {
+    fn f<|>(&self) {  }
+}
+"#,
+        );
+        check_result(refs, "f FN FileId(1) 27..43 30..31 Other", &[]);
+    }
+
+    #[test]
+    fn test_find_all_refs_enum_var_name() {
+        let refs = get_all_refs(
+            r#"
+enum Foo {
+    A,
+    B<|>,
+    C,
+}
+"#,
+        );
+        check_result(refs, "B VARIANT FileId(1) 22..23 22..23 Other", &[]);
+    }
+
+    #[test]
+    fn test_find_all_refs_two_modules() {
+        let (analysis, pos) = analysis_and_position(
+            r#"
+//- /lib.rs
+pub mod foo;
+pub mod bar;
+
+fn f() {
+    let i = foo::Foo { n: 5 };
+}
+
+//- /foo.rs
+use crate::bar;
+
+pub struct Foo {
+    pub n: u32,
+}
+
+fn f() {
+    let i = bar::Bar { n: 5 };
+}
+
+//- /bar.rs
+use crate::foo;
+
+pub struct Bar {
+    pub n: u32,
+}
+
+fn f() {
+    let i = foo::Foo<|> { n: 5 };
+}
+"#,
+        );
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        check_result(
+            refs,
+            "Foo STRUCT FileId(2) 17..51 28..31 Other",
+            &["FileId(1) 53..56 StructLiteral", "FileId(3) 79..82 StructLiteral"],
+        );
+    }
+
+    // `mod foo;` is not in the results because `foo` is an `ast::Name`.
+    // So, there are two references: the first one is a definition of the `foo` module,
+    // which is the whole `foo.rs`, and the second one is in `use foo::Foo`.
+    #[test]
+    fn test_find_all_refs_decl_module() {
+        let (analysis, pos) = analysis_and_position(
+            r#"
+//- /lib.rs
+mod foo<|>;
+
+use foo::Foo;
+
+fn f() {
+    let i = Foo { n: 5 };
+}
+
+//- /foo.rs
+pub struct Foo {
+    pub n: u32,
+}
+"#,
+        );
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        check_result(refs, "foo SOURCE_FILE FileId(2) 0..35 Other", &["FileId(1) 14..17 Other"]);
+    }
+
+    #[test]
+    fn test_find_all_refs_super_mod_vis() {
+        let (analysis, pos) = analysis_and_position(
+            r#"
+//- /lib.rs
+mod foo;
+
+//- /foo.rs
+mod some;
+use some::Foo;
+
+fn f() {
+    let i = Foo { n: 5 };
+}
+
+//- /foo/some.rs
+pub(super) struct Foo<|> {
+    pub n: u32,
+}
+"#,
+        );
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        check_result(
+            refs,
+            "Foo STRUCT FileId(3) 0..41 18..21 Other",
+            &["FileId(2) 20..23 Other", "FileId(2) 47..50 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_with_scope() {
+        let code = r#"
+            //- /lib.rs
+            mod foo;
+            mod bar;
+
+            pub fn quux<|>() {}
+
+            //- /foo.rs
+            fn f() { super::quux(); }
+
+            //- /bar.rs
+            fn f() { super::quux(); }
+        "#;
+
+        let (mock, pos) = MockAnalysis::with_files_and_position(code);
+        let bar = mock.id_of("/bar.rs");
+        let analysis = mock.analysis();
+
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        check_result(
+            refs,
+            "quux FN FileId(1) 19..35 26..30 Other",
+            &["FileId(2) 16..20 StructLiteral", "FileId(3) 16..20 StructLiteral"],
+        );
+
+        let refs =
+            analysis.find_all_refs(pos, Some(SearchScope::single_file(bar))).unwrap().unwrap();
+        check_result(
+            refs,
+            "quux FN FileId(1) 19..35 26..30 Other",
+            &["FileId(3) 16..20 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_macro_def() {
+        let refs = get_all_refs(
+            r#"
+#[macro_export]
+macro_rules! m1<|> { () => (()) }
+
+fn foo() {
+    m1();
+    m1();
+}
+"#,
+        );
+        check_result(
+            refs,
+            "m1 MACRO_CALL FileId(1) 0..46 29..31 Other",
+            &["FileId(1) 63..65 StructLiteral", "FileId(1) 73..75 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_basic_highlight_read_write() {
+        let refs = get_all_refs(
+            r#"
+fn foo() {
+    let mut i<|> = 0;
+    i = i + 1;
+}
+"#,
+        );
+        check_result(
+            refs,
+            "i IDENT_PAT FileId(1) 23..24 Other Write",
+            &["FileId(1) 34..35 Other Write", "FileId(1) 38..39 Other Read"],
+        );
+    }
+
+    #[test]
+    fn test_basic_highlight_field_read_write() {
+        let refs = get_all_refs(
+            r#"
+struct S {
+    f: u32,
+}
+
+fn foo() {
+    let mut s = S{f: 0};
+    s.f<|> = 0;
+}
+"#,
+        );
+        check_result(
+            refs,
+            "f RECORD_FIELD FileId(1) 15..21 15..16 Other",
+            &["FileId(1) 55..56 Other Read", "FileId(1) 68..69 Other Write"],
+        );
+    }
+
+    #[test]
+    fn test_basic_highlight_decl_no_write() {
+        let refs = get_all_refs(
+            r#"
+fn foo() {
+    let i<|>;
+    i = 1;
+}
+"#,
+        );
+        check_result(refs, "i IDENT_PAT FileId(1) 19..20 Other", &["FileId(1) 26..27 Other Write"]);
+    }
+
+    #[test]
+    fn test_find_struct_function_refs_outside_module() {
+        let refs = get_all_refs(
+            r#"
+mod foo {
+    pub struct Foo;
+
+    impl Foo {
+        pub fn new<|>() -> Foo {
+            Foo
+        }
+    }
+}
+
+fn main() {
+    let _f = foo::Foo::new();
+}
+"#,
+        );
+        check_result(
+            refs,
+            "new FN FileId(1) 54..101 61..64 Other",
+            &["FileId(1) 146..149 StructLiteral"],
+        );
+    }
+
+    #[test]
+    fn test_find_all_refs_nested_module() {
+        let code = r#"
+            //- /lib.rs
+            mod foo {
+                mod bar;
+            }
+
+            fn f<|>() {}
+
+            //- /foo/bar.rs
+            use crate::f;
+
+            fn g() {
+                f();
+            }
+        "#;
+
+        let (analysis, pos) = analysis_and_position(code);
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        check_result(
+            refs,
+            "f FN FileId(1) 26..35 29..30 Other",
+            &["FileId(2) 11..12 Other", "FileId(2) 28..29 StructLiteral"],
+        );
+    }
+
+    fn get_all_refs(ra_fixture: &str) -> ReferenceSearchResult {
+        let (analysis, position) = analysis_and_position(ra_fixture);
+        analysis.find_all_refs(position, None).unwrap().unwrap()
+    }
+
+    fn check_result(res: ReferenceSearchResult, expected_decl: &str, expected_refs: &[&str]) {
+        res.declaration().assert_match(expected_decl);
+        assert_eq!(res.references.len(), expected_refs.len());
+        res.references()
+            .iter()
+            .enumerate()
+            .for_each(|(i, r)| ref_assert_match(r, expected_refs[i]));
+    }
+
+    impl Declaration {
+        fn debug_render(&self) -> String {
+            let mut s = format!("{} {:?}", self.nav.debug_render(), self.kind);
+            if let Some(access) = self.access {
+                s.push_str(&format!(" {:?}", access));
+            }
+            s
+        }
+
+        fn assert_match(&self, expected: &str) {
+            let actual = self.debug_render();
+            test_utils::assert_eq_text!(expected.trim(), actual.trim(),);
+        }
+    }
+
+    fn ref_debug_render(r: &Reference) -> String {
+        let mut s = format!("{:?} {:?} {:?}", r.file_range.file_id, r.file_range.range, r.kind);
+        if let Some(access) = r.access {
+            s.push_str(&format!(" {:?}", access));
+        }
+        s
+    }
+
+    fn ref_assert_match(r: &Reference, expected: &str) {
+        let actual = ref_debug_render(r);
+        test_utils::assert_eq_text!(expected.trim(), actual.trim(),);
+    }
+}