Text / matching failures

Find invisible characters that break product-code matching

A zero-width space or non-breaking space can break equality even when a code looks identical. Record position, kind and original text; do not change an identifier without owner approval.

Inspect a string

Separate position and kind

Position	Kind	Visible sample	Decision
2	zero-width space	ABC	Review
4	non-breaking space	C 123	Review
8	tab	123 X	Keep original
—	none	ABC 123 X	Keep original

Positions are zero-based examples. Detection does not mean that removal is safe.

Reproduce it with fixtures

Compare mixed-code.txt with clean-code.txt, then match positions, kinds and decisions in expected.csv. Keep the original product code separate from a display-only proposal.

[...text].map((char, index) => ({
  index, codePoint: char.codePointAt(0), char
}));

Review before changing

Keep the original and record position and kind.
Separate an identifier from display-only text.
Confirm that the owner permits removal or replacement.
If the contract is unknown, review it and use the original as the key.

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Do not change identifiers automatically

An invisible character may be invalid, but not every space or control character is disposable. Until the product-code owner approves the repair, hand off the original and the display proposal separately.