fix: add Angular 20 compatibility for ng add schematic

Angular 20 simplified angular.json by removing outputPath option entirely
(uses sensible defaults). The ng-add schematic now accepts:

- Angular 20+: outputPath undefined (uses default dist/<project>)
- Angular 17-19: outputPath as object { base, browser, ... }
- Earlier: outputPath as string

Fixes #199
See: angular/angular-cli#26675

Author: JohannesHoppe

src/deploy/actions.spec.ts

@@ -191,6 +191,27 @@ describe('Deploy Angular apps', () => {
       // actions.ts successfully handled the object case)
       expect(capturedDir).not.toBeNull();
     });
+
+    it('uses correct dir when outputPath is object with empty browser (Angular 19 SPA style)', async () => {
+      // Angular 19 can use browser: "" to output directly to base folder
+      let capturedDir: string | null = null;
+
+      const mockEngineWithCapture: EngineHost = {
+        run: (dir: string, _options: Schema, _logger: logging.LoggerApi) => {
+          capturedDir = dir;
+          return Promise.resolve();
+        }
+      };
+
+      context.getTargetOptions = (_: Target) =>
+        Promise.resolve({
+          outputPath: { base: 'dist/my-app', browser: '' }
+        } as JsonObject);
+
+      await deploy(mockEngineWithCapture, context, BUILD_TARGET, { noBuild: false });
+
+      expect(capturedDir).toBe('dist/my-app');
+    });
   });
 });
 

src/ng-add.spec.ts

@@ -116,14 +116,18 @@ describe('ng-add', () => {
       );
     });
 
-    it('should throw if app does not have architect configured', async () => {
+    it('should throw if app does not have build target configured', async () => {
       const tree = Tree.empty();
       tree.create(
         'angular.json',
         JSON.stringify({
           version: 1,
           projects: {
-            [PROJECT_NAME]: { projectType: 'application', root: PROJECT_NAME }
+            [PROJECT_NAME]: {
+              projectType: 'application',
+              root: PROJECT_NAME,
+              architect: {}
+            }
           }
         })
       );
@@ -133,7 +137,135 @@ describe('ng-add', () => {
           project: PROJECT_NAME
         })(tree, {} as SchematicContext)
       ).rejects.toThrowError(
-        'Cannot read the output path (architect.build.options.outputPath) of the Angular project "THEPROJECT" in angular.json'
+        /Cannot find build target for the Angular project/
+      );
+    });
+  });
+
+  describe('Angular 17+ outputPath formats', () => {
+    it('should accept Angular 20+ projects without outputPath (uses default)', async () => {
+      const tree = Tree.empty();
+      tree.create(
+        'angular.json',
+        JSON.stringify({
+          version: 1,
+          projects: {
+            [PROJECT_NAME]: {
+              projectType: 'application',
+              root: PROJECT_ROOT,
+              architect: {
+                build: {
+                  builder: '@angular/build:application',
+                  options: {
+                    // Angular 20+ omits outputPath - uses sensible default
+                  }
+                }
+              }
+            }
+          }
+        })
+      );
+
+      const result = await ngAdd({ project: PROJECT_NAME })(
+        tree,
+        {} as SchematicContext
+      );
+
+      const resultConfig = readJSONFromTree(result, 'angular.json');
+      const deployTarget = resultConfig.projects[PROJECT_NAME].architect.deploy;
+      expect(deployTarget.builder).toBe('angular-cli-ghpages:deploy');
+    });
+
+    it('should accept outputPath as object with base property', async () => {
+      const tree = Tree.empty();
+      tree.create(
+        'angular.json',
+        JSON.stringify({
+          version: 1,
+          projects: {
+            [PROJECT_NAME]: {
+              projectType: 'application',
+              root: PROJECT_ROOT,
+              architect: {
+                build: {
+                  options: {
+                    outputPath: { base: 'dist/my-app', browser: '' }
+                  }
+                }
+              }
+            }
+          }
+        })
+      );
+
+      const result = await ngAdd({ project: PROJECT_NAME })(
+        tree,
+        {} as SchematicContext
+      );
+
+      const resultConfig = readJSONFromTree(result, 'angular.json');
+      const deployTarget = resultConfig.projects[PROJECT_NAME].architect.deploy;
+      expect(deployTarget.builder).toBe('angular-cli-ghpages:deploy');
+    });
+
+    it('should accept outputPath object with base and browser properties', async () => {
+      const tree = Tree.empty();
+      tree.create(
+        'angular.json',
+        JSON.stringify({
+          version: 1,
+          projects: {
+            [PROJECT_NAME]: {
+              projectType: 'application',
+              root: PROJECT_ROOT,
+              architect: {
+                build: {
+                  options: {
+                    outputPath: { base: 'dist/app', browser: 'browser', server: 'server' }
+                  }
+                }
+              }
+            }
+          }
+        })
+      );
+
+      const result = await ngAdd({ project: PROJECT_NAME })(
+        tree,
+        {} as SchematicContext
+      );
+
+      const resultConfig = readJSONFromTree(result, 'angular.json');
+      const deployTarget = resultConfig.projects[PROJECT_NAME].architect.deploy;
+      expect(deployTarget.builder).toBe('angular-cli-ghpages:deploy');
+    });
+
+    it('should reject invalid outputPath object without base property', async () => {
+      const tree = Tree.empty();
+      tree.create(
+        'angular.json',
+        JSON.stringify({
+          version: 1,
+          projects: {
+            [PROJECT_NAME]: {
+              projectType: 'application',
+              root: PROJECT_ROOT,
+              architect: {
+                build: {
+                  options: {
+                    outputPath: { browser: 'browser' } // missing base - invalid
+                  }
+                }
+              }
+            }
+          }
+        })
+      );
+
+      await expect(
+        ngAdd({ project: PROJECT_NAME })(tree, {} as SchematicContext)
+      ).rejects.toThrowError(
+        /Invalid outputPath configuration.*Expected undefined.*a string.*an object with a "base" property/
       );
     });
   });

src/ng-add.ts

@@ -41,9 +41,29 @@ export const ngAdd = (options: NgAddOptions) => async (
     );
   }
 
-  if (!project.targets.get('build')?.options?.outputPath) {
+  // Validate build target exists (required for deployment)
+  const buildTarget = project.targets.get('build');
+  if (!buildTarget) {
     throw new SchematicsException(
-      `Cannot read the output path (architect.build.options.outputPath) of the Angular project "${options.project}" in angular.json`
+      `Cannot find build target for the Angular project "${options.project}" in angular.json.`
+    );
+  }
+
+  // outputPath validation:
+  // - Angular 20+: outputPath is omitted (uses default dist/<project-name>)
+  // - Angular 17-19: object format { base: "dist/app", browser: "", ... }
+  // - Earlier versions: string format "dist/app"
+  // See: https://github.com/angular/angular-cli/pull/26675
+  const outputPath = buildTarget.options?.outputPath;
+  const hasValidOutputPath =
+    outputPath === undefined || // Angular 20+ uses sensible defaults
+    typeof outputPath === 'string' ||
+    (typeof outputPath === 'object' && outputPath !== null && 'base' in outputPath);
+
+  if (!hasValidOutputPath) {
+    throw new SchematicsException(
+      `Invalid outputPath configuration for the Angular project "${options.project}" in angular.json. ` +
+      `Expected undefined (default), a string, or an object with a "base" property.`
     );
   }