feat: extends

tomastrajan · tomastrajan · commit 88a569d1a419 · 2026-01-05T12:04:17.000+01:00
diff --git a/.all-contributorsrc b/.all-contributorsrc
@@ -51,6 +51,16 @@
         "maintenance",
         "code"
       ]
+    },
+    {
+      "login": "tomastrajan",
+      "name": "Tomas Trajan",
+      "avatar_url": "https://avatars.githubusercontent.com/u/3764868?v=4",
+      "profile": "http://angularexperts.io",
+      "contributions": [
+        "maintenance",
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,
diff --git a/src/converters/component/component.converter.spec.ts b/src/converters/component/component.converter.spec.ts
@@ -17,7 +17,7 @@ describe('Component converter', () => {
         implementation: '',
         template: '',
         styles: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
@@ -35,7 +35,7 @@ describe('Component converter', () => {
         implementation: '',
         template: '',
         styles: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
@@ -53,7 +53,7 @@ describe('Component converter', () => {
         implementation: '',
         template: '',
         styles: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
diff --git a/src/converters/directive/directive.converter.spec.ts b/src/converters/directive/directive.converter.spec.ts
@@ -14,7 +14,7 @@ describe('Directive converter', () => {
         inputs: [],
         outputs: [],
         implementation: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
@@ -29,7 +29,7 @@ describe('Directive converter', () => {
         inputs: [],
         outputs: [],
         implementation: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
@@ -44,7 +44,7 @@ describe('Directive converter', () => {
         inputs: [],
         outputs: [],
         implementation: '',
-        extends: [],
+        extends: undefined,
         methods: [],
         methodsPublicExplicit: [],
         fieldsPublicExplicit: [],
diff --git a/src/converters/service/service.converter.component.spec.ts b/src/converters/service/service.converter.component.spec.ts
@@ -9,7 +9,7 @@ describe('Service stats converter', () => {
         className: 'first',
         type: NgParselOutputType.SERVICE,
         filePath: '',
-        extends: [],
+        extends: undefined,
         fieldsPublicExplicit: [],
         methods: [],
         methodsPublicExplicit: [],
@@ -18,7 +18,7 @@ describe('Service stats converter', () => {
         className: 'second',
         type: NgParselOutputType.SERVICE,
         filePath: '',
-        extends: [],
+        extends: undefined,
         fieldsPublicExplicit: [],
         methods: [],
         methodsPublicExplicit: [],
@@ -27,7 +27,7 @@ describe('Service stats converter', () => {
         className: 'third',
         type: NgParselOutputType.SERVICE,
         filePath: '',
-        extends: [],
+        extends: undefined,
         fieldsPublicExplicit: [],
         methods: [],
         methodsPublicExplicit: [],
diff --git a/src/parser/component/component.model.ts b/src/parser/component/component.model.ts
@@ -8,7 +8,7 @@ export interface NgParselComponent extends NgParselOutput {
   selector: string;
   standalone: boolean;
   cva: boolean;
-  extends: string[];
+  extends: string | undefined;
   onPush: boolean;
   inputs: NgParselFieldDecorator[];
   outputs: NgParselFieldDecorator[];
diff --git a/src/parser/component/component.parser.spec.ts b/src/parser/component/component.parser.spec.ts
@@ -40,7 +40,7 @@ describe('ComponentParser', () => {
       selector: 'my-test-comp',
       standalone: false,
       cva: false,
-      extends: [],
+      extends: undefined,
       onPush: false,
       template: inlineTemplate,
       styles: [styles],
@@ -134,7 +134,7 @@ describe('ComponentParser', () => {
       selector: 'my-test-comp',
       standalone: true,
       cva: false,
-      extends: [],
+      extends: undefined,
       onPush: false,
       template: inlineTemplate,
       styles: [styles],
diff --git a/src/parser/directive/directive.model.ts b/src/parser/directive/directive.model.ts
@@ -7,7 +7,7 @@ export interface NgParselDirective extends NgParselOutput {
   className: string;
   selector: string;
   standalone: boolean;
-  extends: string[];
+  extends: string | undefined;
   cva: boolean;
   implementation: string;
   inputs: NgParselFieldDecorator[];
diff --git a/src/parser/directive/directive.parser.spec.ts b/src/parser/directive/directive.parser.spec.ts
@@ -32,7 +32,7 @@ describe('DirectiveParser', () => {
       selector: '[myTestDirective]',
       standalone: false,
       cva: false,
-      extends: [],
+      extends: undefined,
       inputs: [
         {
           decorator: '@Input()',
@@ -91,7 +91,7 @@ describe('DirectiveParser', () => {
       selector: '[myTestDirective]',
       standalone: true,
       cva: false,
-      extends: [],
+      extends: undefined,
       inputs: [
         {
           decorator: '@Input()',
diff --git a/src/parser/services/service.model.ts b/src/parser/services/service.model.ts
@@ -3,7 +3,7 @@ import { NgParselMethod } from '../shared/model/method.model.js';
 import { NgParselField } from '../shared/model/field.model.js';
 
 export interface NgParselService extends NgParselOutput {
-  extends: string[];
+  extends: string | undefined;
   fieldsPublicExplicit: NgParselField[];
   methods: NgParselMethod[];
   methodsPublicExplicit: NgParselMethod[];
diff --git a/src/parser/services/service.parser.spec.ts b/src/parser/services/service.parser.spec.ts
@@ -24,7 +24,7 @@ describe('ServiceParser', () => {
       type: NgParselOutputType.SERVICE,
       className,
       filePath,
-      extends: [],
+      extends: undefined,
       fieldsPublicExplicit: [],
       methods: [
         {
@@ -90,7 +90,7 @@ describe('ServiceParser', () => {
       className,
       filePath,
       fieldsPublicExplicit: [],
-      extends: [],
+      extends: undefined,
       methods: [
         {
           name: 'foo',
@@ -148,7 +148,7 @@ describe('ServiceParser', () => {
       type: NgParselOutputType.SERVICE,
       className,
       filePath,
-      extends: [],
+      extends: undefined,
       fieldsPublicExplicit: [
         {
           name: 'counter',
diff --git a/src/parser/shared/parser/extends.parser.spec.ts b/src/parser/shared/parser/extends.parser.spec.ts
@@ -8,16 +8,16 @@ describe('parseExtends', () => {
       export class MyComponent extends BaseComponent {}
     `);
 
-    expect(parseExtends(ast)).toEqual(['BaseComponent']);
+    expect(parseExtends(ast)).toEqual('BaseComponent');
   });
 
-  it('returns an empty array for a component-like class without extends', () => {
+  it('returns an undefined for a component-like class without extends', () => {
     const ast = tsquery.ast(`
       @Component({ selector: 'x' })
       export class MyComponent {}
     `);
 
-    expect(parseExtends(ast)).toEqual([]);
+    expect(parseExtends(ast)).toEqual(undefined);
   });
 
   it('parses extends for a directive-like class with extends', () => {
@@ -26,31 +26,31 @@ describe('parseExtends', () => {
       export class MyDirective extends SomeDirectiveBase {}
     `);
 
-    expect(parseExtends(ast)).toEqual(['SomeDirectiveBase']);
+    expect(parseExtends(ast)).toEqual('SomeDirectiveBase');
   });
 
-  it('returns an empty array for a directive-like class without extends', () => {
+  it('returns an undefined for a directive-like class without extends', () => {
     const ast = tsquery.ast(`
       @Directive({ selector: '[x]' })
       export class MyDirective {}
     `);
 
-    expect(parseExtends(ast)).toEqual([]);
+    expect(parseExtends(ast)).toEqual(undefined);
   });
 
   it('parses extends for a service-like class with generic extends', () => {
     const ast = tsquery.ast(`
       export class MyService extends BaseService<Thing> {}
     `);
 
-    expect(parseExtends(ast)).toEqual(['BaseService']);
+    expect(parseExtends(ast)).toEqual('BaseService');
   });
 
-  it('returns an empty array for a service-like class without extends', () => {
+  it('returns an undefined for a service-like class without extends', () => {
     const ast = tsquery.ast(`
       export class MyService {}
     `);
 
-    expect(parseExtends(ast)).toEqual([]);
+    expect(parseExtends(ast)).toEqual(undefined);
   });
 });
diff --git a/src/parser/shared/parser/extends.parser.ts b/src/parser/shared/parser/extends.parser.ts
@@ -1,21 +1,19 @@
 import * as ts from 'typescript';
 import { tsquery } from '@phenomnomnominal/tsquery';
 
-export function parseExtends(ast: ts.SourceFile): string[] {
+export function parseExtends(ast: ts.SourceFile): string | undefined {
+  // Find identifiers used in extends heritage clauses
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   const identifiers = tsquery(ast, 'HeritageClause > ExpressionWithTypeArguments > Identifier') as any[];
 
-  const result: string[] = [];
-
   for (const id of identifiers) {
-    // id.parent -> ExpressionWithTypeArguments
-    // id.parent.parent -> HeritageClause
     const heritageClause = (id.parent as any)?.parent as ts.HeritageClause | undefined;
     if (!heritageClause) continue;
 
     if (heritageClause.token === ts.SyntaxKind.ExtendsKeyword) {
-      result.push(id.getText());
+      return id.getText();
     }
   }
 
-  return result;
+  return undefined;
 }
