fix: accept 4-8 char primary language subtags per RFC 5646 §2.1#342
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fix: accept 4-8 char primary language subtags per RFC 5646 §2.1#342creed-bratton wants to merge 1 commit intoitalia:mainfrom
creed-bratton wants to merge 1 commit intoitalia:mainfrom
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The switch in isValidBCP47StrictLanguageTag had two dead-end cases:
case n == 4: return false
default: return false // 5-8 chars land here
The regex (group 2) already accepts [A-Z]{4} and [A-Z]{5,8}, so these
tags pass syntactic validation but are then rejected by the switch.
RFC 5646 §2.1 explicitly allows both:
- 4-alpha: reserved for future use
- 5-8 alpha: registered language subtags
golang.org/x/text/language does not cover 4-8 char primary subtags, so
syntactic validation by the regex is sufficient for both cases.
Adds a unit test suite for isValidBCP47StrictLanguageTag covering 2-char,
3-char, 4-char, 5-8 char subtags, with and without region/script/extlang,
grandfathered tags, private-use tags, and invalid inputs.
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go-playground/validator@b599053 added bcp47_strict_language_tag as a built-in validator (go-playground/validator#1489), so our copy is now redundant. Drop validators/bcp47.go and its tests; update bcp47_keys to delegate to the built-in tag via a package-level Validate instance. Closes italia#341, closes italia#342.
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Superseded by go-playground/validator#1489 (merged upstream). Will switch to the built-in validator in a new PR. |
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isValidBCP47StrictLanguageTagrejected 4-8 char primary language subtags because of two dead-end switch cases:RFC 5646 §2.1 allows three forms for the primary language subtag beyond the usual 2-3 alpha ISO 639 codes:
The regex (group 2) already accepts
[A-Z]{4}and[A-Z]{5,8}, so these tags passed syntactic validation only to be rejected by the switch.golang.org/x/text/languagedoes not cover 4-8 char primary subtags, so the regex check is sufficient.Also adds a unit test suite for
isValidBCP47StrictLanguageTag— previously untested directly.