bug #194 [Bug] Locale support improved (SirDomin)

This PR was merged into the 1.0-dev branch.

Discussion
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fixes #188 

paypal supports only 2 en_XX locales, it changes all en locales to en_US

Commits
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82bdc3a add spec to en locale
d6c2cd0 locale processor supports en locale
51623cd pr-fix

Author: Zales0123

spec/Processor/LocaleProcessorSpec.php

@@ -21,4 +21,9 @@ function it_returns_same_locale_if_it_is_valid(): void
         $this->process('ja_JP_TRADITIONAL')->shouldReturn('ja_JP_TRADITIONAL');
         $this->process('sd_Arab_PK')->shouldReturn('sd_Arab_PK');
     }
+
+    function it_returns_correct_locale_for_en_locale(): void
+    {
+        $this->process('en')->shouldReturn('en_US');
+    }
 }

src/Processor/LocaleProcessor.php

@@ -14,10 +14,15 @@ public function process(string $locale): string
             return $locale;
         }
 
+        if ($locale === 'en') {
+            return 'en_US';
+        }
+
         $locales = array_filter(Locales::getLocales(), function (string $targetLocale) use ($locale): bool {
             return
                 strpos($targetLocale, $locale) === 0 &&
-                strpos($targetLocale, '_') !== false
+                strpos($targetLocale, '_') !== false &&
+                strlen($targetLocale) === 5
             ;
         });