1 files changed, 389 insertions, 0 deletions

diff --git a/crates/ra_ide/src/references.rs b/crates/ra_ide/src/references.rs
new file mode 100644
index 000000000..21a1ea69e
--- /dev/null
+++ b/crates/ra_ide/src/references.rs
@@ -0,0 +1,389 @@
+//! 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 classify;
+mod name_definition;
+mod rename;
+mod search_scope;
+
+use hir::Source;
+use once_cell::unsync::Lazy;
+use ra_db::{SourceDatabase, SourceDatabaseExt};
+use ra_prof::profile;
+use ra_syntax::{algo::find_node_at_offset, ast, AstNode, SourceFile, SyntaxNode, TextUnit};
+
+use crate::{
+    db::RootDatabase, display::ToNav, FilePosition, FileRange, NavigationTarget, RangeInfo,
+};
+
+pub(crate) use self::{
+    classify::{classify_name, classify_name_ref},
+    name_definition::{NameDefinition, NameKind},
+    rename::rename,
+};
+
+pub use self::search_scope::SearchScope;
+
+#[derive(Debug, Clone)]
+pub struct ReferenceSearchResult {
+    declaration: NavigationTarget,
+    references: Vec<FileRange>,
+}
+
+impl ReferenceSearchResult {
+    pub fn declaration(&self) -> &NavigationTarget {
+        &self.declaration
+    }
+
+    pub fn references(&self) -> &[FileRange] {
+        &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 FileRanges
+impl IntoIterator for ReferenceSearchResult {
+    type Item = FileRange;
+    type IntoIter = std::vec::IntoIter<FileRange>;
+
+    fn into_iter(mut self) -> Self::IntoIter {
+        let mut v = Vec::with_capacity(self.len());
+        v.push(FileRange { file_id: self.declaration.file_id(), range: self.declaration.range() });
+        v.append(&mut self.references);
+        v.into_iter()
+    }
+}
+
+pub(crate) fn find_all_refs(
+    db: &RootDatabase,
+    position: FilePosition,
+    search_scope: Option<SearchScope>,
+) -> Option<RangeInfo<ReferenceSearchResult>> {
+    let parse = db.parse(position.file_id);
+    let syntax = parse.tree().syntax().clone();
+    let RangeInfo { range, info: (name, def) } = find_name(db, &syntax, position)?;
+
+    let declaration = match def.kind {
+        NameKind::Macro(mac) => mac.to_nav(db),
+        NameKind::Field(field) => field.to_nav(db),
+        NameKind::AssocItem(assoc) => assoc.to_nav(db),
+        NameKind::Def(def) => NavigationTarget::from_def(db, def)?,
+        NameKind::SelfType(imp) => imp.to_nav(db),
+        NameKind::Local(local) => local.to_nav(db),
+        NameKind::GenericParam(_) => return None,
+    };
+
+    let search_scope = {
+        let base = def.search_scope(db);
+        match search_scope {
+            None => base,
+            Some(scope) => base.intersection(&scope),
+        }
+    };
+
+    let references = process_definition(db, def, name, search_scope);
+
+    Some(RangeInfo::new(range, ReferenceSearchResult { declaration, references }))
+}
+
+fn find_name<'a>(
+    db: &RootDatabase,
+    syntax: &SyntaxNode,
+    position: FilePosition,
+) -> Option<RangeInfo<(String, NameDefinition)>> {
+    if let Some(name) = find_node_at_offset::<ast::Name>(&syntax, position.offset) {
+        let def = classify_name(db, Source::new(position.file_id.into(), &name))?;
+        let range = name.syntax().text_range();
+        return Some(RangeInfo::new(range, (name.text().to_string(), def)));
+    }
+    let name_ref = find_node_at_offset::<ast::NameRef>(&syntax, position.offset)?;
+    let def = classify_name_ref(db, Source::new(position.file_id.into(), &name_ref))?;
+    let range = name_ref.syntax().text_range();
+    Some(RangeInfo::new(range, (name_ref.text().to_string(), def)))
+}
+
+fn process_definition(
+    db: &RootDatabase,
+    def: NameDefinition,
+    name: String,
+    scope: SearchScope,
+) -> Vec<FileRange> {
+    let _p = profile("process_definition");
+
+    let pat = name.as_str();
+    let mut refs = vec![];
+
+    for (file_id, search_range) in scope {
+        let text = db.file_text(file_id);
+        let parse = Lazy::new(|| SourceFile::parse(&text));
+
+        for (idx, _) in text.match_indices(pat) {
+            let offset = TextUnit::from_usize(idx);
+
+            if let Some(name_ref) =
+                find_node_at_offset::<ast::NameRef>(parse.tree().syntax(), offset)
+            {
+                let range = name_ref.syntax().text_range();
+                if let Some(search_range) = search_range {
+                    if !range.is_subrange(&search_range) {
+                        continue;
+                    }
+                }
+                if let Some(d) = classify_name_ref(db, Source::new(file_id.into(), &name_ref)) {
+                    if d == def {
+                        refs.push(FileRange { file_id, range });
+                    }
+                }
+            }
+        }
+    }
+    refs
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        mock_analysis::{analysis_and_position, single_file_with_position, MockAnalysis},
+        ReferenceSearchResult, SearchScope,
+    };
+
+    #[test]
+    fn test_find_all_refs_for_local() {
+        let code = r#"
+    fn main() {
+        let mut i = 1;
+        let j = 1;
+        i = i<|> + j;
+
+        {
+            i = 0;
+        }
+
+        i = 5;
+    }"#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 5);
+    }
+
+    #[test]
+    fn test_find_all_refs_for_param_inside() {
+        let code = r#"
+    fn foo(i : u32) -> u32 {
+        i<|>
+    }"#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 2);
+    }
+
+    #[test]
+    fn test_find_all_refs_for_fn_param() {
+        let code = r#"
+    fn foo(i<|> : u32) -> u32 {
+        i
+    }"#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 2);
+    }
+
+    #[test]
+    fn test_find_all_refs_field_name() {
+        let code = r#"
+            //- /lib.rs
+            struct Foo {
+                pub spam<|>: u32,
+            }
+
+            fn main(s: Foo) {
+                let f = s.spam;
+            }
+        "#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 2);
+    }
+
+    #[test]
+    fn test_find_all_refs_impl_item_name() {
+        let code = r#"
+            //- /lib.rs
+            struct Foo;
+            impl Foo {
+                fn f<|>(&self) {  }
+            }
+        "#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 1);
+    }
+
+    #[test]
+    fn test_find_all_refs_enum_var_name() {
+        let code = r#"
+            //- /lib.rs
+            enum Foo {
+                A,
+                B<|>,
+                C,
+            }
+        "#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 1);
+    }
+
+    #[test]
+    fn test_find_all_refs_two_modules() {
+        let code = 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 (analysis, pos) = analysis_and_position(code);
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        assert_eq!(refs.len(), 3);
+    }
+
+    // `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 code = r#"
+            //- /lib.rs
+            mod foo<|>;
+
+            use foo::Foo;
+
+            fn f() {
+                let i = Foo { n: 5 };
+            }
+
+            //- /foo.rs
+            pub struct Foo {
+                pub n: u32,
+            }
+        "#;
+
+        let (analysis, pos) = analysis_and_position(code);
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        assert_eq!(refs.len(), 2);
+    }
+
+    #[test]
+    fn test_find_all_refs_super_mod_vis() {
+        let code = 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 (analysis, pos) = analysis_and_position(code);
+        let refs = analysis.find_all_refs(pos, None).unwrap().unwrap();
+        assert_eq!(refs.len(), 3);
+    }
+
+    #[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();
+        assert_eq!(refs.len(), 3);
+
+        let refs =
+            analysis.find_all_refs(pos, Some(SearchScope::single_file(bar))).unwrap().unwrap();
+        assert_eq!(refs.len(), 2);
+    }
+
+    #[test]
+    fn test_find_all_refs_macro_def() {
+        let code = r#"
+        #[macro_export]
+        macro_rules! m1<|> { () => (()) }
+
+        fn foo() {
+            m1();
+            m1();
+        }"#;
+
+        let refs = get_all_refs(code);
+        assert_eq!(refs.len(), 3);
+    }
+
+    fn get_all_refs(text: &str) -> ReferenceSearchResult {
+        let (analysis, position) = single_file_with_position(text);
+        analysis.find_all_refs(position, None).unwrap().unwrap()
+    }
+}