Fix locale-dependent parsing for English month names #100
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Tests were failing in non-US locales (GB, FR, etc.) due to: - AM/PM parsing differences (US: "AM" vs UK: "am") - Timezone abbreviation ambiguity (PST resolves differently) - Date formatting variations across locales Added JUnit @rule to ensure all tests run with US locale and UTC timezone. The rule saves the original locale/timezone before each test and restores them afterward in a finally block. This approach follows the standard JUnit TestRule pattern and ensures test isolation without affecting production code. Fixes google#93
English text patterns (month names, weekday names, AM/PM) now explicitly use Locale.ENGLISH when creating DateTimeFormatter instances. This ensures consistent parsing behavior regardless of the JVM's default locale. Fixes google#99
fluentfuture
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Jan 22, 2026
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Summary
Fixes #99
English text patterns (month names, weekday names, AM/PM) now explicitly use
Locale.ENGLISHwhen creatingDateTimeFormatterinstances. This ensures consistent parsing behavior regardless of the JVM's default locale.Problem
In non-English locales (e.g., French, German),
DateTimeFormats.formatOf("Jan 11 2011")would fail becauseDateTimeFormatter.ofPattern()uses the system default locale. In French locale, "Jan" would be interpreted as "janv." (French abbreviation), causing parse failure.Solution
Extended
inferLocaleIfNeeded()to detect English locale tokens (month abbreviations, full month names, weekday abbreviations, full weekday names, AM/PM markers) and explicitly setLocale.ENGLISHfor those patterns.Changes
inferLocaleIfNeeded()to handle English locale tokens (lines 325-335)LOCAL_DATE_FORMATTERSinitialization to usemapKeyValue()for signature access (line 195)inferLocaleIfNeeded()call to placeholder pattern path (line 303)