[yu2971512385-ui]

isISO4217 is documented in the README as checking for an officially assigned currency code, but its list was copied from Wikipedia and has gone stale. Checked against ISO 4217 list one as published on 2026-09-17, it accepts four codes the register has withdrawn and rejects three it assigns.

	code	why
remove	ANG	replaced by XCG on 2025-03-31
remove	BGN	Bulgaria adopted the euro on 2026-01-01
remove	SLL	replaced by SLE on 2022-04-01
remove	ZWL	replaced by ZWG on 2024-04-05
add	XAD	Arab Accounting Dinar
add	XCG	Caribbean Guilder
add	ZWG	Zimbabwe Gold

After the change the set matches the register exactly: 178 codes, nothing extra and nothing missing.

On the four removals

They are a behaviour change — strings that used to validate no longer will — so they are worth a deliberate look. Two things suggest they are what the validator already intends:

• the README says "officially assigned", and these four are not;
• the existing suite already asserts that HRK and CUC, withdrawn in 2023 and 2021, are invalid. ZWL and SLL are the same case, just more recent.

If you would rather keep withdrawn codes accepted for backwards compatibility, say so and I will cut this down to the three additions.

Relation to #2842

#2842 by @simonkundrik adds XCG and ZWG and has been open since August. This change includes both of those, plus XAD and the four removals. Whichever you prefer, that PR found the problem first.

Tests

XAD, XCG and ZWG added to valid; ANG, BGN, SLL and ZWL added to invalid, alongside the HRK and CUC already there. The test fails on master and passes with the fix. Full suite: 323 passing, npm run lint clean. The source comment now cites the register and the date of the list it was checked against, instead of Wikipedia.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (9ff3424) to head (535201d).

Additional details and impacted files

@@            Coverage Diff            @@
##            master     #2936   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files          114       114           
  Lines         2599      2599           
  Branches       658       658           
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  Hits          2599      2599           

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