diff --git a/packages/angular_devkit/build_angular/src/testing/builder-harness.ts b/packages/angular_devkit/build_angular/src/testing/builder-harness.ts
index 5c881e9e7b04..05ba0d5d2df5 100644
--- a/packages/angular_devkit/build_angular/src/testing/builder-harness.ts
+++ b/packages/angular_devkit/build_angular/src/testing/builder-harness.ts
@@ -22,7 +22,7 @@ import {
 import { WorkspaceHost } from '@angular-devkit/architect/node';
 import { TestProjectHost } from '@angular-devkit/architect/testing';
 import { getSystemPath, json, logging } from '@angular-devkit/core';
-import { existsSync, readFileSync, readdirSync } from 'node:fs';
+import { existsSync, readFileSync, readdirSync, statSync } from 'node:fs';
 import fs from 'node:fs/promises';
 import { dirname, join } from 'node:path';
 import {
@@ -351,6 +351,12 @@ export class BuilderHarness<T> {
     return existsSync(fullPath);
   }
 
+  hasDirectory(path: string): boolean {
+    const fullPath = this.resolvePath(path);
+
+    return statSync(fullPath, { throwIfNoEntry: false })?.isDirectory() ?? false;
+  }
+
   hasFileMatch(directory: string, pattern: RegExp): boolean {
     const fullPath = this.resolvePath(directory);
 
diff --git a/packages/angular_devkit/build_angular/src/testing/jasmine-helpers.ts b/packages/angular_devkit/build_angular/src/testing/jasmine-helpers.ts
index ade4a0b7978f..1d28cb0f2ff8 100644
--- a/packages/angular_devkit/build_angular/src/testing/jasmine-helpers.ts
+++ b/packages/angular_devkit/build_angular/src/testing/jasmine-helpers.ts
@@ -42,6 +42,9 @@ export class JasmineBuilderHarness<T> extends BuilderHarness<T> {
   expectFile(path: string): HarnessFileMatchers {
     return expectFile(path, this);
   }
+  expectDirectory(path: string): HarnessDirectoryMatchers {
+    return expectDirectory(path, this);
+  }
 }
 
 export interface HarnessFileMatchers {
@@ -51,6 +54,11 @@ export interface HarnessFileMatchers {
   readonly size: jasmine.Matchers<number>;
 }
 
+export interface HarnessDirectoryMatchers {
+  toExist(): boolean;
+  toNotExist(): boolean;
+}
+
 /**
  * Add a Jasmine expectation filter to an expectation that always fails with a message.
  * @param base The base expectation (`expect(...)`) to use.
@@ -125,3 +133,23 @@ export function expectFile<T>(path: string, harness: BuilderHarness<T>): Harness
     },
   };
 }
+
+export function expectDirectory<T>(
+  path: string,
+  harness: BuilderHarness<T>,
+): HarnessDirectoryMatchers {
+  return {
+    toExist() {
+      const exists = harness.hasDirectory(path);
+      expect(exists).toBe(true, 'Expected directory to exist: ' + path);
+
+      return exists;
+    },
+    toNotExist() {
+      const exists = harness.hasDirectory(path);
+      expect(exists).toBe(false, 'Expected directory to not exist: ' + path);
+
+      return !exists;
+    },
+  };
+}