1 files changed, 103 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/ide/src/annotations/fn_references.rs b/src/tools/rust-analyzer/crates/ide/src/annotations/fn_references.rs
new file mode 100644
index 000000000..0cadf125f
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/ide/src/annotations/fn_references.rs
@@ -0,0 +1,103 @@
+//! This module implements a methods and free functions search in the specified file.
+//! We have to skip tests, so cannot reuse file_structure module.
+
+use hir::Semantics;
+use ide_assists::utils::test_related_attribute;
+use ide_db::RootDatabase;
+use syntax::{ast, ast::HasName, AstNode, SyntaxNode, TextRange};
+
+use crate::FileId;
+
+pub(super) fn find_all_methods(
+    db: &RootDatabase,
+    file_id: FileId,
+) -> Vec<(TextRange, Option<TextRange>)> {
+    let sema = Semantics::new(db);
+    let source_file = sema.parse(file_id);
+    source_file.syntax().descendants().filter_map(|it| method_range(it)).collect()
+}
+
+fn method_range(item: SyntaxNode) -> Option<(TextRange, Option<TextRange>)> {
+    ast::Fn::cast(item).and_then(|fn_def| {
+        if test_related_attribute(&fn_def).is_some() {
+            None
+        } else {
+            Some((
+                fn_def.syntax().text_range(),
+                fn_def.name().map(|name| name.syntax().text_range()),
+            ))
+        }
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use syntax::TextRange;
+
+    use crate::fixture;
+    use crate::TextSize;
+    use std::ops::RangeInclusive;
+
+    #[test]
+    fn test_find_all_methods() {
+        let (analysis, pos) = fixture::position(
+            r#"
+            fn private_fn() {$0}
+
+            pub fn pub_fn() {}
+
+            pub fn generic_fn<T>(arg: T) {}
+        "#,
+        );
+
+        let refs = super::find_all_methods(&analysis.db, pos.file_id);
+        check_result(&refs, &[3..=13, 27..=33, 47..=57]);
+    }
+
+    #[test]
+    fn test_find_trait_methods() {
+        let (analysis, pos) = fixture::position(
+            r#"
+            trait Foo {
+                fn bar() {$0}
+                fn baz() {}
+            }
+        "#,
+        );
+
+        let refs = super::find_all_methods(&analysis.db, pos.file_id);
+        check_result(&refs, &[19..=22, 35..=38]);
+    }
+
+    #[test]
+    fn test_skip_tests() {
+        let (analysis, pos) = fixture::position(
+            r#"
+            //- /lib.rs
+            #[test]
+            fn foo() {$0}
+
+            pub fn pub_fn() {}
+
+            mod tests {
+                #[test]
+                fn bar() {}
+            }
+        "#,
+        );
+
+        let refs = super::find_all_methods(&analysis.db, pos.file_id);
+        check_result(&refs, &[28..=34]);
+    }
+
+    fn check_result(refs: &[(TextRange, Option<TextRange>)], expected: &[RangeInclusive<u32>]) {
+        assert_eq!(refs.len(), expected.len());
+
+        for (i, &(full, focus)) in refs.iter().enumerate() {
+            let range = &expected[i];
+            let item = focus.unwrap_or(full);
+            assert_eq!(TextSize::from(*range.start()), item.start());
+            assert_eq!(TextSize::from(*range.end()), item.end());
+        }
+    }
+}