Folding ranges (#32)

Author: wkillerud

extension/test/electron/definition/folding-ranges.test.js

@@ -0,0 +1,39 @@
+const assert = require('node:assert');
+const path = require('node:path');
+const vscode = require('vscode');
+const { showFile, sleepCI } = require('../util');
+
+const stylesUri = vscode.Uri.file(
+  path.resolve(__dirname, 'fixtures', 'styles.scss')
+);
+
+before(async () => {
+  await showFile(stylesUri);
+  await sleepCI();
+});
+
+after(async () => {
+  await vscode.commands.executeCommand('workbench.action.closeAllEditors');
+});
+
+/**
+ * @param {import('vscode').Uri} documentUri
+ * @param {Array<import('vscode').Position>} positions
+ * @returns {Promise<Array<import('vscode').FoldingRange>>}
+ */
+async function getFoldingRanges(documentUri, positions) {
+  const result = await vscode.commands.executeCommand(
+    'vscode.executeFoldingRangeProvider',
+    documentUri,
+    positions
+  );
+  return result;
+}
+
+test('gets document folding ranges', async () => {
+  const [result] = await getFoldingRanges(stylesUri, [
+    new vscode.Position(7, 5),
+  ]);
+
+  assert.ok(result, 'Should have gotten folding ranges');
+});

pkgs/sass_language_server/lib/src/language_server.dart

@@ -176,6 +176,7 @@ class LanguageServer {
           documentHighlightProvider: Either2.t1(true),
           documentLinkProvider: DocumentLinkOptions(resolveProvider: false),
           documentSymbolProvider: Either2.t1(true),
+          foldingRangeProvider: Either3.t1(true),
           referencesProvider: Either2.t1(true),
           renameProvider: Either2.t2(RenameOptions(prepareProvider: true)),
           selectionRangeProvider: Either3.t1(true),
@@ -433,6 +434,26 @@ class LanguageServer {
         }
       });
 
+      _connection.onFoldingRanges((params) async {
+        try {
+          var document = _documents.get(params.textDocument.uri);
+          if (document == null) {
+            return [];
+          }
+
+          var configuration = _getLanguageConfiguration(document);
+          if (configuration.foldingRanges.enabled) {
+            var result = _ls.getFoldingRanges(document);
+            return result;
+          } else {
+            return [];
+          }
+        } on Exception catch (e) {
+          _log.debug(e.toString());
+          return [];
+        }
+      });
+
       _connection.onSelectionRanges((params) async {
         try {
           var document = _documents.get(params.textDocument.uri);

pkgs/sass_language_services/lib/src/configuration/language_configuration.dart

@@ -6,9 +6,10 @@ class FeatureConfiguration {
 
 class LanguageConfiguration {
   late final FeatureConfiguration definition;
-  late final FeatureConfiguration highlights;
   late final FeatureConfiguration documentSymbols;
   late final FeatureConfiguration documentLinks;
+  late final FeatureConfiguration foldingRanges;
+  late final FeatureConfiguration highlights;
   late final FeatureConfiguration references;
   late final FeatureConfiguration rename;
   late final FeatureConfiguration selectionRanges;
@@ -21,6 +22,8 @@ class LanguageConfiguration {
         enabled: config?['documentSymbols']?['enabled'] as bool? ?? true);
     documentLinks = FeatureConfiguration(
         enabled: config?['documentLinks']?['enabled'] as bool? ?? true);
+    foldingRanges = FeatureConfiguration(
+        enabled: config?['foldingRanges']?['enabled'] as bool? ?? true);
     highlights = FeatureConfiguration(
         enabled: config?['highlights']?['enabled'] as bool? ?? true);
     references = FeatureConfiguration(

pkgs/sass_language_services/lib/src/features/folding_ranges/folding_ranges_feature.dart

@@ -0,0 +1,47 @@
+import 'package:lsp_server/lsp_server.dart' as lsp;
+import 'package:sass_language_services/sass_language_services.dart';
+
+import '../go_to_definition/scope.dart';
+import '../go_to_definition/scope_visitor.dart';
+import '../go_to_definition/scoped_symbols.dart';
+import '../language_feature.dart';
+
+class FoldingRangesFeature extends LanguageFeature {
+  FoldingRangesFeature({required super.ls});
+
+  List<lsp.FoldingRange> getFoldingRanges(TextDocument document) {
+    var stylesheet = ls.parseStylesheet(document);
+
+    var symbols = ls.cache.getDocumentSymbols(document) ??
+        ScopedSymbols(
+          stylesheet,
+          document.languageId == 'sass' ? Dialect.indented : Dialect.scss,
+        );
+    ls.cache.setDocumentSymbols(document, symbols);
+
+    var result = <lsp.FoldingRange>[];
+    // Omit the global scope.
+    for (var childScope in symbols.globalScope.children) {
+      result.addAll(_toFoldingRanges(document, childScope));
+    }
+    return result;
+  }
+
+  List<lsp.FoldingRange> _toFoldingRanges(TextDocument document, Scope scope) {
+    var result = <lsp.FoldingRange>[];
+    result.add(_toFoldingRange(document, scope));
+    if (scope.children.isEmpty) {
+      return result;
+    }
+    for (var childScope in scope.children) {
+      result.addAll(_toFoldingRanges(document, childScope));
+    }
+    return result;
+  }
+
+  lsp.FoldingRange _toFoldingRange(TextDocument document, Scope scope) {
+    var startLine = document.positionAt(scope.offset).line;
+    var endLine = document.positionAt(scope.offset + scope.length).line;
+    return lsp.FoldingRange(startLine: startLine, endLine: endLine);
+  }
+}

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

@@ -60,6 +60,28 @@ class ScopeVisitor with sass.RecursiveStatementVisitor {
     return null;
   }
 
+  @override
+  void visitAtRule(sass.AtRule node) {
+    if (node.children != null) {
+      var span = node.span;
+      _addScope(
+        offset: span.start.offset,
+        length: span.length,
+      );
+    }
+    super.visitAtRule(node);
+  }
+
+  @override
+  void visitAtRootRule(sass.AtRootRule node) {
+    var span = node.span;
+    _addScope(
+      offset: span.start.offset,
+      length: span.length,
+    );
+    super.visitAtRootRule(node);
+  }
+
   @override
   void visitDeclaration(node) {
     var isCustomProperty =
@@ -241,6 +263,21 @@ class ScopeVisitor with sass.RecursiveStatementVisitor {
     super.visitIfRule(node);
   }
 
+  @override
+  void visitIncludeRule(sass.IncludeRule node) {
+    var span = node.span;
+
+    var argsEndIndex = node.arguments.span.end.offset - span.start.offset;
+    var scopeIndex = span.text.indexOf(openBracketOrNewline, argsEndIndex);
+
+    _addScope(
+      offset: span.start.offset + scopeIndex,
+      length: span.length - scopeIndex,
+    );
+
+    super.visitIncludeRule(node);
+  }
+
   @override
   void visitMixinRule(node) {
     var span = node.span;

pkgs/sass_language_services/lib/src/language_services.dart

@@ -3,6 +3,7 @@ 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/document_highlights/document_highlights_feature.dart';
 import 'package:sass_language_services/src/features/find_references/find_references_feature.dart';
+import 'package:sass_language_services/src/features/folding_ranges/folding_ranges_feature.dart';
 import 'package:sass_language_services/src/features/go_to_definition/go_to_definition_feature.dart';
 import 'package:sass_language_services/src/features/rename/rename_feature.dart';
 import 'package:sass_language_services/src/features/selection_ranges/selection_ranges_feature.dart';
@@ -23,8 +24,9 @@ class LanguageServices {
   late final DocumentHighlightsFeature _documentHighlights;
   late final DocumentLinksFeature _documentLinks;
   late final DocumentSymbolsFeature _documentSymbols;
-  late final GoToDefinitionFeature _goToDefinition;
+  late final FoldingRangesFeature _foldingRanges;
   late final FindReferencesFeature _findReferences;
+  late final GoToDefinitionFeature _goToDefinition;
   late final RenameFeature _rename;
   late final SelectionRangesFeature _selectionRanges;
   late final WorkspaceSymbolsFeature _workspaceSymbols;
@@ -36,8 +38,9 @@ class LanguageServices {
     _documentHighlights = DocumentHighlightsFeature(ls: this);
     _documentLinks = DocumentLinksFeature(ls: this);
     _documentSymbols = DocumentSymbolsFeature(ls: this);
-    _goToDefinition = GoToDefinitionFeature(ls: this);
     _findReferences = FindReferencesFeature(ls: this);
+    _foldingRanges = FoldingRangesFeature(ls: this);
+    _goToDefinition = GoToDefinitionFeature(ls: this);
     _rename = RenameFeature(ls: this);
     _selectionRanges = SelectionRangesFeature(ls: this);
     _workspaceSymbols = WorkspaceSymbolsFeature(ls: this);
@@ -70,6 +73,10 @@ class LanguageServices {
     return _workspaceSymbols.findWorkspaceSymbols(query);
   }
 
+  List<lsp.FoldingRange> getFoldingRanges(TextDocument document) {
+    return _foldingRanges.getFoldingRanges(document);
+  }
+
   List<lsp.SelectionRange> getSelectionRanges(
       TextDocument document, List<lsp.Position> positions) {
     return _selectionRanges.getSelectionRanges(document, positions);

pkgs/sass_language_services/test/features/folding_ranges/folding_ranges_test.dart

@@ -0,0 +1,83 @@
+import 'package:lsp_server/lsp_server.dart' as lsp;
+import 'package:sass_language_services/sass_language_services.dart';
+import 'package:test/test.dart';
+
+import '../../memory_file_system.dart';
+import '../../test_client_capabilities.dart';
+
+final fs = MemoryFileSystem();
+final ls = LanguageServices(fs: fs, clientCapabilities: getCapabilities());
+
+lsp.FoldingRange fr(int startLine, int endLine) {
+  return lsp.FoldingRange(
+    startLine: startLine,
+    endLine: endLine,
+  );
+}
+
+void main() {
+  group('folding ranges', () {
+    setUp(() {
+      ls.cache.clear();
+    });
+
+    test('style rules', () {
+      var document = fs.createDocument('''
+.foo {
+  color: red;
+
+  .bar {
+    color: blue;
+  }
+}
+''');
+
+      var result = ls.getFoldingRanges(document);
+      expect(result, hasLength(2));
+      expect(
+        result,
+        equals([
+          fr(0, 6),
+          fr(3, 5),
+        ]),
+      );
+    });
+
+    test('mixin rules', () {
+      var document = fs.createDocument('''@mixin foo {
+  color: red;
+
+  .bar {
+    color: blue;
+  }
+}
+''');
+
+      var result = ls.getFoldingRanges(document);
+      expect(result, hasLength(2));
+      expect(
+        result,
+        equals([
+          fr(0, 6),
+          fr(3, 5),
+        ]),
+      );
+    });
+
+    test('include rules', () {
+      var document = fs.createDocument('''@include foo {
+  --color-foo: red;
+}
+''');
+
+      var result = ls.getFoldingRanges(document);
+      expect(result, hasLength(1));
+      expect(
+        result,
+        equals([
+          fr(0, 2),
+        ]),
+      );
+    });
+  });
+}