refactor(language-service): ensure compatibility with noImplicitOverride (#42512)

Adds the `override` keyword to the `language-service` sources to ensure
compatibility with `noImplicitOverride`.

PR Close #42512

packages/language-service/ivy/template_target.ts

@@ -142,11 +142,22 @@ export interface TwoWayBindingContext {
   nodes: [t.BoundAttribute, t.BoundEvent];
 }
 
+/**
+ * Special marker AST that can be used when the cursor is within the `sourceSpan` but not
+ * the key or value span of a node with key/value spans.
+ */
+class OutsideKeyValueMarkerAst extends e.AST {
+  visit(): null {
+    return null;
+  }
+}
+
 /**
  * This special marker is added to the path when the cursor is within the sourceSpan but not the key
  * or value span of a node with key/value spans.
  */
-const OUTSIDE_K_V_MARKER = new e.AST(new ParseSpan(-1, -1), new e.AbsoluteSourceSpan(-1, -1));
+const OUTSIDE_K_V_MARKER =
+    new OutsideKeyValueMarkerAst(new ParseSpan(-1, -1), new e.AbsoluteSourceSpan(-1, -1));
 
 /**
  * Return the template AST node or expression AST node that most accurately
@@ -415,7 +426,7 @@ class ExpressionVisitor extends e.RecursiveAstVisitor {
     super();
   }
 
-  visit(node: e.AST, path: Array<t.Node|e.AST>) {
+  override visit(node: e.AST, path: Array<t.Node|e.AST>) {
     if (node instanceof e.ASTWithSource) {
       // In order to reduce noise, do not include `ASTWithSource` in the path.
       // For the purpose of source spans, there is no difference between

packages/language-service/src/completions.ts

@@ -408,23 +408,23 @@ class ExpressionVisitor extends NullTemplateVisitor {
     return Array.from(this.completions.values());
   }
 
-  visitDirectiveProperty(ast: BoundDirectivePropertyAst): void {
+  override visitDirectiveProperty(ast: BoundDirectivePropertyAst): void {
     this.processExpressionCompletions(ast.value);
   }
 
-  visitElementProperty(ast: BoundElementPropertyAst): void {
+  override visitElementProperty(ast: BoundElementPropertyAst): void {
     this.processExpressionCompletions(ast.value);
   }
 
-  visitEvent(ast: BoundEventAst): void {
+  override visitEvent(ast: BoundEventAst): void {
     this.processExpressionCompletions(ast.handler);
   }
 
-  visitElement(): void {
+  override visitElement(): void {
     // no-op for now
   }
 
-  visitAttr(ast: AttrAst) {
+  override visitAttr(ast: AttrAst) {
     const binding = getBindingDescriptor(ast.name);
     if (binding && binding.kind === ATTR.KW_MICROSYNTAX) {
       // This a template binding given by micro syntax expression.
@@ -459,7 +459,7 @@ class ExpressionVisitor extends NullTemplateVisitor {
     }
   }
 
-  visitReference(_ast: ReferenceAst, context: ElementAst) {
+  override visitReference(_ast: ReferenceAst, context: ElementAst) {
     context.directives.forEach(dir => {
       const {exportAs} = dir.directive;
       if (exportAs) {
@@ -469,7 +469,7 @@ class ExpressionVisitor extends NullTemplateVisitor {
     });
   }
 
-  visitBoundText(ast: BoundTextAst) {
+  override visitBoundText(ast: BoundTextAst) {
     if (inSpan(this.position, ast.value.sourceSpan)) {
       const completions = getExpressionCompletions(
           this.getExpressionScope(), ast.value, this.position, this.info.template);

packages/language-service/src/expression_diagnostics.ts

@@ -42,11 +42,11 @@ function getReferences(info: ng.DiagnosticTemplateInfo): SymbolDeclaration[] {
   }
 
   const visitor = new class extends RecursiveTemplateAstVisitor {
-    visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
+    override visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
       super.visitEmbeddedTemplate(ast, context);
       processReferences(ast.references);
     }
-    visitElement(ast: ElementAst, context: any): any {
+    override visitElement(ast: ElementAst, context: any): any {
       super.visitElement(ast, context);
       processReferences(ast.references);
     }
@@ -257,38 +257,38 @@ class ExpressionDiagnosticsVisitor extends RecursiveTemplateAstVisitor {
     this.path = new AstPath<TemplateAst>([]);
   }
 
-  visitDirective(ast: DirectiveAst, context: any): any {
+  override visitDirective(ast: DirectiveAst, context: any): any {
     // Override the default child visitor to ignore the host properties of a directive.
     if (ast.inputs && ast.inputs.length) {
       templateVisitAll(this, ast.inputs, context);
     }
   }
 
-  visitBoundText(ast: BoundTextAst): void {
+  override visitBoundText(ast: BoundTextAst): void {
     this.push(ast);
     this.diagnoseExpression(ast.value, ast.sourceSpan.start.offset, false);
     this.pop();
   }
 
-  visitDirectiveProperty(ast: BoundDirectivePropertyAst): void {
+  override visitDirectiveProperty(ast: BoundDirectivePropertyAst): void {
     this.push(ast);
     this.diagnoseExpression(ast.value, this.attributeValueLocation(ast), false);
     this.pop();
   }
 
-  visitElementProperty(ast: BoundElementPropertyAst): void {
+  override visitElementProperty(ast: BoundElementPropertyAst): void {
     this.push(ast);
     this.diagnoseExpression(ast.value, this.attributeValueLocation(ast), false);
     this.pop();
   }
 
-  visitEvent(ast: BoundEventAst): void {
+  override visitEvent(ast: BoundEventAst): void {
     this.push(ast);
     this.diagnoseExpression(ast.handler, this.attributeValueLocation(ast), true);
     this.pop();
   }
 
-  visitVariable(ast: VariableAst): void {
+  override visitVariable(ast: VariableAst): void {
     const directive = this.directiveSummary;
     if (directive && ast.value) {
       const context = this.info.query.getTemplateContext(directive.type.reference)!;
@@ -304,13 +304,13 @@ class ExpressionDiagnosticsVisitor extends RecursiveTemplateAstVisitor {
     }
   }
 
-  visitElement(ast: ElementAst, context: any): void {
+  override visitElement(ast: ElementAst, context: any): void {
     this.push(ast);
     super.visitElement(ast, context);
     this.pop();
   }
 
-  visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
+  override visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
     const previousDirectiveSummary = this.directiveSummary;
 
     this.push(ast);

packages/language-service/src/expressions.ts

@@ -17,7 +17,7 @@ type AstPath = AstPathBase<AST>;
 function findAstAt(ast: AST, position: number, excludeEmpty: boolean = false): AstPath {
   const path: AST[] = [];
   const visitor = new class extends RecursiveAstVisitor {
-    visit(ast: AST) {
+    override visit(ast: AST) {
       if ((!excludeEmpty || ast.sourceSpan.start < ast.sourceSpan.end) &&
           inSpan(position, ast.sourceSpan)) {
         const isNotNarrower = path.length && !isNarrower(ast.span, path[path.length - 1].span);

packages/language-service/src/locate_symbol.ts

@@ -258,28 +258,28 @@ function findParentOfBinding(
       }
     }
 
-    visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
+    override visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
       return this.visitChildren(context, visit => {
         visit(ast.directives);
         visit(ast.children);
       });
     }
 
-    visitElement(ast: ElementAst, context: any): any {
+    override visitElement(ast: ElementAst, context: any): any {
       return this.visitChildren(context, visit => {
         visit(ast.directives);
         visit(ast.children);
       });
     }
 
-    visitDirective(ast: DirectiveAst) {
+    override visitDirective(ast: DirectiveAst) {
       const result = this.visitChildren(ast, visit => {
         visit(ast.inputs);
       });
       return result;
     }
 
-    visitDirectiveProperty(ast: BoundDirectivePropertyAst, context: DirectiveAst) {
+    override visitDirectiveProperty(ast: BoundDirectivePropertyAst, context: DirectiveAst) {
       if (ast === binding) {
         res = context;
       }

packages/language-service/src/typescript_host.ts

@@ -23,7 +23,7 @@ import {AstResult, Declaration, DeclarationError, DiagnosticMessageChain, Langua
  * syntactically incorrect templates.
  */
 export class DummyHtmlParser extends HtmlParser {
-  parse(): ParseTreeResult {
+  override parse(): ParseTreeResult {
     return new ParseTreeResult([], []);
   }
 }

packages/language-service/src/typescript_symbols.ts

@@ -351,7 +351,7 @@ class TypeWrapper implements Symbol {
 // If stringIndexType a primitive type(e.g. 'string'), the Symbol is undefined;
 // and in AstType.resolvePropertyRead method, the Symbol.type should get the right type.
 class StringIndexTypeWrapper extends TypeWrapper {
-  public readonly type = new TypeWrapper(this.tsType, this.context);
+  public override readonly type = new TypeWrapper(this.tsType, this.context);
 }
 
 class SymbolWrapper implements Symbol {

packages/language-service/src/utils.ts

@@ -107,7 +107,7 @@ export function findTemplateAstAt(ast: TemplateAst[], position: number): Templat
       }
     }
 
-    visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
+    override visitEmbeddedTemplate(ast: EmbeddedTemplateAst, context: any): any {
       return this.visitChildren(context, visit => {
         // Ignore reference, variable and providers
         visit(ast.attrs);
@@ -116,7 +116,7 @@ export function findTemplateAstAt(ast: TemplateAst[], position: number): Templat
       });
     }
 
-    visitElement(ast: ElementAst, context: any): any {
+    override visitElement(ast: ElementAst, context: any): any {
       return this.visitChildren(context, visit => {
         // Ingnore providers
         visit(ast.attrs);
@@ -128,7 +128,7 @@ export function findTemplateAstAt(ast: TemplateAst[], position: number): Templat
       });
     }
 
-    visitDirective(ast: DirectiveAst, context: any): any {
+    override visitDirective(ast: DirectiveAst, context: any): any {
       // Ignore the host properties of a directive
       const result = this.visitChildren(context, visit => {
         visit(ast.inputs);

packages/language-service/test/mocks.ts

@@ -180,7 +180,7 @@ export class DiagnosticContext {
       };
       const urlResolver = createOfflineCompileUrlResolver();
       const htmlParser = new class extends HtmlParser {
-        parse(): ParseTreeResult {
+        override parse(): ParseTreeResult {
           return new ParseTreeResult([], []);
         }
       };