test(compat/each): replace each duplicate tests with an alias check against forEach

[Antoliny0919]

Summary

We could delegate the specific test cases for the alias each to forEach. Since forEach is already thoroughly tested and each is simply an alias of it, that should be sufficient.

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Project	Deployment	Actions	Updated (UTC)
es-toolkit	Ready	Preview, Comment	Jul 10, 2026 7:29am

[Antoliny0919]

I noticed that alias functions didn't have dedicated test files before. How about keeping the test file, as it is now, but only adding a test that verifies the alias references the same implementation as the original function?

[raon0211]

As far as I understand, that's actually already what this PR does.

each.spec.ts stays right where it is; we just trimmed it down to a single test confirming each is the same implementation as forEach:

describe('each', () => {
  it('should be an alias of forEach', () => {
    expect(each).toBe(forEach);
  });
});

Only the duplicated behavioral cases were removed, since forEach.spec.ts already covers those. Let me know if you meant something a bit different, happy to adjust!

[Antoliny0919]

As far as I understand, that's actually already what this PR does.

each.spec.ts stays right where it is; we just trimmed it down to a single test confirming each is the same implementation as forEach:

describe('each', () => {
  it('should be an alias of forEach', () => {
    expect(each).toBe(forEach);
  });
});

Only the duplicated behavioral cases were removed, since forEach.spec.ts already covers those. Let me know if you meant something a bit different, happy to adjust!

I actually meant asking whether we should add the same kind of test for the other aliases too, like first, extend ...
It looks like this is already being worked on :) -> #1883

[raon0211]

Thanks!