Fix confusing exception message in Dictionary.CopyTo when index exceeds array length - #132465
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… when index exceeds array length (#132571) Backport of #132465 to release/11.0 /cc @jeffhandley @aw0lid ## Customer Impact - [x] Customer reported - [ ] Found internally Customer-reported in #131782. A positive `index` beyond the destination array length causes generic `Dictionary<TKey, TValue>.CopyTo` to throw `ArgumentOutOfRangeException` with the misleading message "Non-negative number required." This fix keeps the exception type and parameter while using a clearer existing message. The separately reported non-generic path is unchanged. The change in #132465 was also a community contribution to improve the message. ## Regression - [ ] Yes - [x] No ## Testing Existing tests cover this invalid index and assert the exception type, but not the exception message. No tests were added. ## Risk Low. Only the message resource used for the exception is changed, reusing a different existing resource with a clearer message. Co-authored-by: Ahmed Waleed <ahmedwalidahmed.0@gmail.com>
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Fixes #131782
Description
This PR improves the exception message produced by
Dictionary<TKey, TValue>'sCopyTomethods when the providedindexexceeds the target array's length.Instead of throwing the misleading
Non-negative number requiredmessage, it now utilizesThrowHelper.ThrowArgumentOutOfRange_IndexMustBeLessOrEqualException()to yield a clearer message while maintaining the existingArgumentOutOfRangeExceptiontype.Customer Impact
Prevents confusion when developers encounter unexpected index-related validation errors during collection copy operations.