[assert] RangeError: Maximum call stack size exceeded

After trying to update some projects to AWS CDK 1.68.0 I’m seeing the following behavior in our unit tests:

    RangeError: Maximum call stack size exceeded

      at deepCopy (node_modules/@aws-cdk/cloudformation-diff/lib/diff-template.ts:168:18)
      at deepCopy (node_modules/@aws-cdk/cloudformation-diff/lib/diff-template.ts:176:18)
          at Array.map (<anonymous>)
      at deepCopy (node_modules/@aws-cdk/cloudformation-diff/lib/diff-template.ts:170:14)
[...]
      at deepCopy (node_modules/@aws-cdk/cloudformation-diff/lib/diff-template.ts:176:18)
          at Array.map (<anonymous>)
      at deepCopy (node_modules/@aws-cdk/cloudformation-diff/lib/diff-template.ts:170:14)

cdk synth for the stack in question seems to produce a proper template. Any ideas what might cause this?

Reproduction Steps

The test cases are pretty much in this form:

import { expect as expectCDK, matchTemplate, MatchStyle } from '@aws-cdk/assert';
import * as cdk from '@aws-cdk/core';
import { ExampleStack } from '../lib/example-stack';

test('ExampleStack', () => {
  const app = new cdk.App();
  // WHEN
  const stack = new ExampleStack(app, `ecs-stack`);

  // THEN
  const expected = {
    'Resources': {
        /// ... resource definitions
    }
  };

  expectCDK(stack).to(matchTemplate(expected, MatchStyle.SUPERSET));
});

Environment

• CLI Version : 1.68.0
• Framework Version: 1.68.0
• Node.js Version: v14.8.0
• OS : macOs
• Language (Version): TypeScript 4

Other

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This is 🐛 Bug Report

[MAGilleeney]

Sorry for commenting on closed issue, however this is the only solution i found that helped me. Markusl is correct that this was from a version mismatch however in my case i had a version mismatch when I added a new contruct so i used npm-check -u to update all versions. Running my tests gave the exact same error above, even though my versions were in sync.

Deleting package-lock.json & node_modules and reinstalling packages fixed the issue.

[markusl]

@nija-at I see. I think what is different in our case was including a CDK construct with a different version (<1.68.0) of CDK libraries (and assert library) as part of the main CDK project with a library version 1.68.0. I wasn’t able to figure out why this happened, but now after upgrading the main project to CDK 1.70.0 the problem went away. I’ll get back to this if it happens again.