fix(testing): safely handle circular deps in component testing plugin (…

…#20852)

packages/cypress/src/utils/ct-helpers.spec.ts

@@ -0,0 +1,38 @@
+import { ProjectGraph } from '@nx/devkit';
+import { isCtProjectUsingBuildProject } from './ct-helpers';
+
+describe('ct-helpers', () => {
+  /**
+   * app1 -> lib1 -> lib2 -> lib3 -> lib1
+   *                              -> lib4 -> lib5
+   * lib6
+   */
+  const projectGraph: ProjectGraph = {
+    dependencies: {
+      app1: [{ source: 'app1', target: 'lib1', type: 'static' }],
+      lib1: [{ source: 'lib1', target: 'lib2', type: 'static' }],
+      lib2: [{ source: 'lib2', target: 'lib3', type: 'static' }],
+      lib3: [
+        { source: 'lib3', target: 'lib1', type: 'static' },
+        { source: 'lib3', target: 'lib4', type: 'static' },
+      ],
+      lib4: [{ source: 'lib4', target: 'lib5', type: 'static' }],
+      lib5: [],
+      lib6: [],
+    },
+    nodes: {},
+    externalNodes: {},
+  };
+
+  it('should handle circular deps and find the relation', () => {
+    expect(isCtProjectUsingBuildProject(projectGraph, 'app1', 'lib5')).toBe(
+      true
+    );
+  });
+
+  it('should handle circular deps and find no relation', () => {
+    expect(isCtProjectUsingBuildProject(projectGraph, 'app1', 'lib6')).toBe(
+      false
+    );
+  });
+});

packages/cypress/src/utils/ct-helpers.ts

@@ -45,8 +45,13 @@ export function getTempTailwindPath(context: ExecutorContext) {
 export function isCtProjectUsingBuildProject(
   graph: ProjectGraph,
   parentProjectName: string,
-  childProjectName: string
+  childProjectName: string,
+  seen = new Set<string>()
 ): boolean {
+  if (seen.has(parentProjectName)) {
+    return false;
+  }
+  seen.add(parentProjectName);
   const isProjectDirectDep = graph.dependencies[parentProjectName].some(
     (p) => p.target === childProjectName
   );
@@ -62,7 +67,8 @@ export function isCtProjectUsingBuildProject(
       isCtProjectUsingBuildProject(
         graph,
         maybeIntermediateProject.target,
-        childProjectName
+        childProjectName,
+        seen
       )
     ) {
       return true;