fix(cli): acknowledge produces duplicate entries (#793)

Fixes #767 

---
By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache-2.0 license

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Signed-off-by: github-actions <[email protected]>
Co-authored-by: github-actions <[email protected]>

Author: kaizencc

packages/aws-cdk/lib/cli/cdk-toolkit.ts

@@ -206,9 +206,9 @@ export class CdkToolkit {
   }
 
   public async acknowledge(noticeId: string) {
-    const acks = this.props.configuration.context.get('acknowledged-issue-numbers') ?? [];
-    acks.push(Number(noticeId));
-    this.props.configuration.context.set('acknowledged-issue-numbers', acks);
+    const acks = new Set(this.props.configuration.context.get('acknowledged-issue-numbers') ?? []);
+    acks.add(Number(noticeId));
+    this.props.configuration.context.set('acknowledged-issue-numbers', Array.from(acks));
     await this.props.configuration.saveContext();
   }
 

packages/aws-cdk/test/commands/acknowledge.test.ts

@@ -0,0 +1,32 @@
+import { CdkToolkit } from '../../lib/cli/cdk-toolkit';
+import { CliIoHost } from '../../lib/cli/io-host';
+import { Configuration } from '../../lib/cli/user-configuration';
+
+const ioHost = CliIoHost.instance({}, true);
+const ioHelper = ioHost.asIoHelper();
+
+describe('acknowledge command', () => {
+  let configuration: Configuration;
+  let toolkit: CdkToolkit;
+
+  beforeEach(async () => {
+    configuration = await Configuration.fromArgs(ioHelper);
+    toolkit = new CdkToolkit({
+      ioHost,
+      configuration,
+      sdkProvider: {} as any,
+      cloudExecutable: {} as any,
+      deployments: {} as any,
+    });
+    jest.clearAllMocks();
+  });
+
+  test('acknowledge same ID twice', async () => {
+    // WHEN
+    await toolkit.acknowledge('12345');
+    await toolkit.acknowledge('12345');
+
+    // THEN
+    expect(configuration.context.get('acknowledged-issue-numbers')).toEqual([12345]);
+  });
+});