Enhance renaming to include identifiers that are generated from the original symbol

Co-authored-by: Jake Goulding <jake.goulding@integer32.com>

Author: Veykril

crates/hir/src/semantics.rs

@@ -222,6 +222,21 @@ impl<DB: HirDatabase> Semantics<'_, DB> {
         self.imp.descend_node_at_offset(node, offset).filter_map(|mut it| it.find_map(N::cast))
     }
 
+    // FIXME: Rethink this API
+    pub fn find_namelike_at_offset_with_descend<'slf>(
+        &'slf self,
+        node: &SyntaxNode,
+        offset: TextSize,
+    ) -> impl Iterator<Item = ast::NameLike> + 'slf {
+        node.token_at_offset(offset)
+            .map(move |token| self.descend_into_macros_no_opaque(token))
+            .map(|descendants| descendants.into_iter().filter_map(move |it| it.value.parent()))
+            // re-order the tokens from token_at_offset by returning the ancestors with the smaller first nodes first
+            // See algo::ancestors_at_offset, which uses the same approach
+            .kmerge_by(|left, right| left.text_range().len().lt(&right.text_range().len()))
+            .filter_map(ast::NameLike::cast)
+    }
+
     pub fn resolve_range_pat(&self, range_pat: &ast::RangePat) -> Option<Struct> {
         self.imp.resolve_range_pat(range_pat).map(Struct::from)
     }

crates/ide-assists/src/handlers/remove_underscore.rs

@@ -1,6 +1,7 @@
 use ide_db::{
     assists::AssistId,
     defs::{Definition, NameClass, NameRefClass},
+    rename::RenameDefinition,
 };
 use syntax::{AstNode, ast};
 
@@ -61,7 +62,7 @@ pub(crate) fn remove_underscore(acc: &mut Assists, ctx: &AssistContext<'_>) -> O
         "Remove underscore from a used variable",
         text_range,
         |builder| {
-            let changes = def.rename(&ctx.sema, new_name).unwrap();
+            let changes = def.rename(&ctx.sema, new_name, RenameDefinition::Yes).unwrap();
             builder.source_change = changes;
         },
     )

crates/ide-db/src/rename.rs

@@ -70,15 +70,19 @@ macro_rules! _bail {
 }
 pub use _bail as bail;
 
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub enum RenameDefinition {
+    Yes,
+    No,
+}
+
 impl Definition {
     pub fn rename(
         &self,
         sema: &Semantics<'_, RootDatabase>,
         new_name: &str,
+        rename_definition: RenameDefinition,
     ) -> Result<SourceChange> {
-        // We append `r#` if needed.
-        let new_name = new_name.trim_start_matches("r#");
-
         // self.krate() returns None if
         // self is a built-in attr, built-in type or tool module.
         // it is not allowed for these defs to be renamed.
@@ -103,8 +107,10 @@ impl Definition {
                 bail!("Cannot rename a builtin attr.")
             }
             Definition::SelfType(_) => bail!("Cannot rename `Self`"),
-            Definition::Macro(mac) => rename_reference(sema, Definition::Macro(mac), new_name),
-            def => rename_reference(sema, def, new_name),
+            Definition::Macro(mac) => {
+                rename_reference(sema, Definition::Macro(mac), new_name, rename_definition)
+            }
+            def => rename_reference(sema, def, new_name, rename_definition),
         }
     }
 
@@ -328,6 +334,7 @@ fn rename_reference(
     sema: &Semantics<'_, RootDatabase>,
     def: Definition,
     new_name: &str,
+    rename_definition: RenameDefinition,
 ) -> Result<SourceChange> {
     let ident_kind = IdentifierKind::classify(new_name)?;
 
@@ -366,11 +373,12 @@ fn rename_reference(
             source_edit_from_references(references, def, new_name, file_id.edition(sema.db)),
         )
     }));
-
-    // This needs to come after the references edits, because we change the annotation of existing edits
-    // if a conflict is detected.
-    let (file_id, edit) = source_edit_from_def(sema, def, new_name, &mut source_change)?;
-    source_change.insert_source_edit(file_id, edit);
+    if rename_definition == RenameDefinition::Yes {
+        // This needs to come after the references edits, because we change the annotation of existing edits
+        // if a conflict is detected.
+        let (file_id, edit) = source_edit_from_def(sema, def, new_name, &mut source_change)?;
+        source_change.insert_source_edit(file_id, edit);
+    }
     Ok(source_change)
 }
 

crates/ide-diagnostics/src/handlers/incorrect_case.rs

@@ -1,5 +1,5 @@
 use hir::{CaseType, InFile, db::ExpandDatabase};
-use ide_db::{assists::Assist, defs::NameClass};
+use ide_db::{assists::Assist, defs::NameClass, rename::RenameDefinition};
 use syntax::AstNode;
 
 use crate::{
@@ -44,7 +44,7 @@ fn fixes(ctx: &DiagnosticsContext<'_>, d: &hir::IncorrectCase) -> Option<Vec<Ass
     let label = format!("Rename to {}", d.suggested_text);
     let mut res = unresolved_fix("change_case", &label, frange.range);
     if ctx.resolve.should_resolve(&res.id) {
-        let source_change = def.rename(&ctx.sema, &d.suggested_text);
+        let source_change = def.rename(&ctx.sema, &d.suggested_text, RenameDefinition::Yes);
         res.source_change = Some(source_change.ok().unwrap_or_default());
     }