Test for go to definition

Author: wkillerud

pkgs/sass_language_services/lib/src/features/go_to_definition/go_to_definition_feature.dart

@@ -9,19 +9,18 @@ import 'scope_visitor.dart';
 class GoToDefinitionFeature extends LanguageFeature {
   GoToDefinitionFeature({required super.ls});
 
-  /// Find the definition of whatever is at [position] in [document] if possible.
-  ///
   /// Returns a Location with:
   ///
   ///   1. The URI of the document containing the definition.
   ///   2. The selectionRange (or "nameRange") of the definition.
   ///
-  Future<lsp.Location?> findDefinition(
+  Future<lsp.Location?> goToDefinition(
       TextDocument document, lsp.Position position) async {
     var stylesheet = ls.parseStylesheet(document);
 
     // Find the node whose definition we're looking for.
     var offset = document.offsetAt(position);
+    // TODO: you are here. Figure out why the search isn't working the way you think.
     var node = stylesheet.accept(NodeAtOffsetVisitor(offset));
     if (node == null) {
       return null;

pkgs/sass_language_services/lib/src/features/node_at_offset_visitor.dart

@@ -18,7 +18,7 @@ class NodeAtOffsetVisitor implements sass.AstSearchVisitor<sass.AstNode> {
       }
     }
 
-    if (node.span.end.offset > _offset) {
+    if (node.span.start.offset > _offset) {
       return _candidate;
     }
 

pkgs/sass_language_services/lib/src/language_services.dart

@@ -1,6 +1,7 @@
 import 'package:lsp_server/lsp_server.dart' as lsp;
 import 'package:sass_api/sass_api.dart' as sass;
 import 'package:sass_language_services/sass_language_services.dart';
+import 'package:sass_language_services/src/features/go_to_definition/go_to_definition_feature.dart';
 
 import 'features/document_links/document_links_feature.dart';
 import 'features/document_symbols/document_symbols_feature.dart';
@@ -17,6 +18,7 @@ class LanguageServices {
 
   late final DocumentLinksFeature _documentLinks;
   late final DocumentSymbolsFeature _documentSymbols;
+  late final GoToDefinitionFeature _goToDefinitionFeature;
   late final WorkspaceSymbolsFeature _workspaceSymbols;
 
   LanguageServices({
@@ -25,6 +27,7 @@ class LanguageServices {
   }) : cache = LanguageServicesCache() {
     _documentLinks = DocumentLinksFeature(ls: this);
     _documentSymbols = DocumentSymbolsFeature(ls: this);
+    _goToDefinitionFeature = GoToDefinitionFeature(ls: this);
     _workspaceSymbols = WorkspaceSymbolsFeature(ls: this);
   }
 
@@ -45,6 +48,11 @@ class LanguageServices {
     return _workspaceSymbols.findWorkspaceSymbols(query);
   }
 
+  Future<lsp.Location?> goToDefinition(
+      TextDocument document, lsp.Position position) {
+    return _goToDefinitionFeature.goToDefinition(document, position);
+  }
+
   sass.Stylesheet parseStylesheet(TextDocument document) {
     return cache.getStylesheet(document);
   }

pkgs/sass_language_services/test/features/go_to_definition/go_to_definition_test.dart

@@ -2,16 +2,38 @@ import 'package:sass_language_services/sass_language_services.dart';
 import 'package:test/test.dart';
 
 import '../../memory_file_system.dart';
+import '../../position_utils.dart';
+import '../../range_matchers.dart';
 import '../../test_client_capabilities.dart';
 
 final fs = MemoryFileSystem();
 final ls = LanguageServices(fs: fs, clientCapabilities: getCapabilities());
+
 void main() {
-  group('selectors', () {
+  group('sass variables', () {
     setUp(() {
       ls.cache.clear();
     });
 
+    test('in a different document', () async {
+      fs.createDocument(r'$b: #000;', uri: 'colors.scss');
+
+      var document = fs.createDocument(r'''
+@use "colors";
+
+.a {
+  color: $b;
+}
+''');
+      var result = await ls.goToDefinition(document, at(line: 3, char: 10));
+
+      expect(result, isNotNull);
+      expect(result!.range, StartsAtLine(0));
+      expect(result.range, EndsAtLine(0));
+      expect(result.range, StartsAtCharacter(0));
+      expect(result.range, EndsAtCharacter(2));
 
+      expect(result.uri.toString(), endsWith('colors.scss'));
+    });
   });
 }

pkgs/sass_language_services/test/position_utils.dart

@@ -0,0 +1,5 @@
+import 'package:lsp_server/lsp_server.dart' as lsp;
+
+lsp.Position at({required int line, required int char}) {
+  return lsp.Position(character: char, line: line);
+}