# Refactor: Remove ForInIterator from Builtin/Intrinsic System

[rajat552]

Summary

Removed ForInIterator from the builtin/intrinsic registration system.

---

Why

The for-in iterator is an internal engine mechanism — it is never visible to JavaScript code.

Therefore, it should not be registered as a builtin intrinsic like Array or Map.

This change is a cleanup and optimization:

• Reduces unnecessary intrinsic initialization
• Aligns better with spec intent
• Removes unnecessary runtime overhead

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Closes #4677

[rajat552]

@jedel1043 review this pr and tell me if their is any issue

[zhuzhu81998]

11 CIs are failing due to failed compilation.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	52,862	52,862	0
Passed	49,497	49,497	0
Ignored	2,261	2,255	-6
Failed	1,104	1,110	+6
Panics	0	0	0
Conformance	93.63%	93.63%	0.00%

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.65%. Comparing base (6ddc2b4) to head (673fff5).
⚠️ Report is 675 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4689      +/-   ##
==========================================
+ Coverage   47.24%   56.65%   +9.40%     
==========================================
  Files         476      548      +72     
  Lines       46892    60073   +13181     
==========================================
+ Hits        22154    34033   +11879     
- Misses      24738    26040    +1302     

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[rajat552]

@zhuzhu81998 review my code i made required changes