From 48b356d9c1c791aaaf0f5d2898905e99675f66d7 Mon Sep 17 00:00:00 2001
From: Colum Ferry <cferry09@gmail.com>
Date: Wed, 19 Apr 2023 09:46:13 +0100
Subject: [PATCH] fix(angular): throw error when generating component with
 multiple candidate modules (#16332)

---
 .../generators/component/component.spec.ts    | 41 +++++++++++++++++++
 .../src/generators/component/lib/module.ts    |  4 +-
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/packages/angular/src/generators/component/component.spec.ts b/packages/angular/src/generators/component/component.spec.ts
index 1cae01a176f34..ac9b481e7f043 100644
--- a/packages/angular/src/generators/component/component.spec.ts
+++ b/packages/angular/src/generators/component/component.spec.ts
@@ -735,6 +735,47 @@ describe('component Generator', () => {
         "
       `);
     });
+
+    it('should throw an error when there are more than one candidate modules that the component can be added to', async () => {
+      // ARRANGE
+      const tree = createTreeWithEmptyWorkspace({ layout: 'apps-libs' });
+      addProjectConfiguration(tree, 'lib1', {
+        projectType: 'library',
+        sourceRoot: 'libs/lib1/src',
+        root: 'libs/lib1',
+      });
+      tree.write(
+        'libs/lib1/src/lib/lib.module.ts',
+        `
+    import { NgModule } from '@angular/core';
+    
+    @NgModule({
+      declarations: [],
+      exports: []
+    })
+    export class LibModule {}`
+      );
+      tree.write(
+        'libs/lib1/src/lib/lib2.module.ts',
+        `
+    import { NgModule } from '@angular/core';
+    
+    @NgModule({
+      declarations: [],
+      exports: []
+    })
+    export class Lib2Module {}`
+      );
+
+      // ACT & ASSERT
+      await expect(
+        componentGenerator(tree, {
+          name: 'example',
+          project: 'lib1',
+          path: 'libs/lib1/src/lib',
+        })
+      ).rejects.toThrow();
+    });
   });
 
   describe('secondary entry points', () => {
diff --git a/packages/angular/src/generators/component/lib/module.ts b/packages/angular/src/generators/component/lib/module.ts
index 97164560f71e4..8b5b665e355e2 100644
--- a/packages/angular/src/generators/component/lib/module.ts
+++ b/packages/angular/src/generators/component/lib/module.ts
@@ -72,7 +72,9 @@ function findModule(
     if (filteredMatches.length == 1) {
       return filteredMatches[0];
     } else if (filteredMatches.length > 1) {
-      return null;
+      throw new Error(
+        "Found more than one candidate module to add the component to. Please specify which module the component should be added to by using the '--module' option."
+      );
     }
 
     dir = dirname(dir);