Make TestCafe show an object diff

Question

We're using TestCafe for end-to-end testing, and I'm finding myself looking at an error like this:

AssertionError: expected [ Array(5) ] to deeply equal [ Array(5) ]

I'd like error messages like this to include a diff. I know object diffing modules are available on npm, but I'd like to add it in such a way that I don't have to import this library any time I'm asserting object equality.

score 1 · Answer 1 · answered Jan 14 '20 at 07:48

I wrote a very similar typescript function which involves a bread first search through all properties of an object. I slightly modified it for your purpose. Maybe it would work. I didn't tested it.

isPrimitiveType(o) {
  const t = typeof o;
  return t == 'string' || t == 'number' || t == 'boolean';
}

printDiff(obj: any, userPref: any) {
    if (obj === undefined || obj === null) {
      return;
    }
    for (let k in obj) {
      let prop = obj[k];
      if (isPrimitiveType(prop)) {
        if (!userPref[k]) {
          console.log(userPref[k], ' not matches');
        } 
      } else {
        if (!userPref[k]) {
          console.log(userPref[k], ' not matches');
        } else {
          this.setUserPrefs(obj[k], userPref[k]);
        }
      }
    }
}

Nice function! But how would I set this up with TestCafe? – bigblind Jan 14 '20 at 08:20 — bigblind, Jan 14 '20 at 08:20
I'm not knowledgeable about TestCafe, sorry – canbax Jan 14 '20 at 08:29 — canbax, Jan 14 '20 at 08:29

score 1 · Answer 2 · edited Feb 20 '21 at 08:40

1

The latest TestCafe version (1.11.0) shows the object differences.

edited Feb 20 '21 at 08:40

mlosev

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answered Jan 15 '20 at 10:07

Alex Kamaev

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Make TestCafe show an object diff

2 Answers2