Avoiding multiple Cache::remember() calls when loading translators.

The problem was there was no fallback translator for newly created instances,
so had to move the code around.

src/I18n/I18n.php

@@ -37,14 +37,6 @@ class I18n {
 	protected static $_collection;
 
 /**
- * The name of the default formatter to use for newly created
- * translators
- *
- * @var string
- */
-	protected static $_defaultFormatter = 'default';
-
-/**
  * Returns the translators collection instance. It can be used
  * for getting specific translators based of their name and locale
  * or to configure some aspect of future translations that are not yet constructed.
@@ -115,6 +107,17 @@ class I18n {
 		if ($loader !== null) {
 			$packages = static::translators()->getPackages();
 			$locale = $locale ?: static::defaultLocale();
+
+			if ($name !== 'default') {
+				$loader = function() use ($loader) {
+					$package = $loader();
+					if (!$package->getFallback()) {
+						$package->setFallback('default');
+					}
+					return $package;
+				};
+			}
+
 			$packages->set($name, $locale, $loader);
 			return;
 		}
@@ -126,11 +129,7 @@ class I18n {
 			static::translators()->setLocale($locale);
 		}
 
-		try {
-			$translator = $translators->get($name);
-		} catch (LoadException $e) {
-			$translator = static::_fallbackTranslator($name, $locale);
-		}
+		$translator = $translators->get($name);
 
 		if (isset($currentLocale)) {
 			$translators->setLocale($currentLocale);
@@ -223,11 +222,7 @@ class I18n {
  * @return string The name of the formatter.
  */
 	public static function defaultFormatter($name = null) {
-		if ($name === null) {
-			return static::$_defaultFormatter;
-		}
-
-		static::$_defaultFormatter = $name;
+		return static::translators()->defaultFormatter($name);
 	}
 
 /**
@@ -240,30 +235,4 @@ class I18n {
 		static::$_collection = null;
 	}
 
-/**
- * Returns a new translator instance for the given name and locale
- * based of conventions.
- *
- * @param string $name The translation package name.
- * @param string $locale The locale to create the translator for.
- * @return \Aura\Intl\Translator
- */
-	protected static function _fallbackTranslator($name, $locale) {
-		$chain = new ChainMessagesLoader([
-			new MessagesFileLoader($name, $locale, 'mo'),
-			new MessagesFileLoader($name, $locale, 'po')
-		]);
-
-		// \Aura\Intl\Package by default uses formatter configured with key "basic".
-		// and we want to make sure the cake domain always uses the default formatter
-		$formatter = $name === 'cake' ? 'default' : static::$_defaultFormatter;
-		$chain = function() use ($formatter, $chain) {
-			$package = $chain();
-			$package->setFormatter($formatter);
-			return $package;
-		};
-		static::translator($name, $locale, $chain);
-		return static::translators()->get($name);
-	}
-
 }

src/I18n/TranslatorRegistry.php

@@ -31,7 +31,16 @@ class TranslatorRegistry extends TranslatorLocator {
  *
  * @var array
  */
-	protected $_loader;
+	protected $_loaders;
+
+
+/**
+ * The name of the default formatter to use for newly created
+ * translators from the fallback loader
+ *
+ * @var string
+ */
+	protected $_defaultFormatter = 'default';
 
 /**
  * Gets a translator from the registry by package for a locale.
@@ -44,6 +53,10 @@ class TranslatorRegistry extends TranslatorLocator {
  * for the given locale.
  */
 	public function get($name, $locale = null) {
+		if (!$name) {
+			return null;
+		}
+
 		if ($locale === null) {
 			$locale = $this->getLocale();
 		}
@@ -54,11 +67,13 @@ class TranslatorRegistry extends TranslatorLocator {
 				try {
 					return parent::get($name, $locale);
 				} catch (\Aura\Intl\Exception $e) {
-					if (!isset($this->_loaders[$name])) {
-						throw $e;
-					}
-					return $this->_getFromLoader($name, $locale);
 				}
+
+				if (!isset($this->_loaders[$name])) {
+					$this->registerLoader($name, $this->_partialLoader());
+				}
+
+				return $this->_getFromLoader($name, $locale);
 			}, '_cake_core_');
 		}
 
@@ -81,6 +96,59 @@ class TranslatorRegistry extends TranslatorLocator {
 	}
 
 /**
+ * Sets the name of the default messages formatter to use for future
+ * translator instances.
+ *
+ * If called with no arguments, it will return the currently configured value.
+ *
+ * @param string $name The name of the formatter to use.
+ * @return string The name of the formatter.
+ */
+	public function defaultFormatter($name = null) {
+		if ($name === null) {
+			return $this->_defaultFormatter;
+		}
+		return $this->_defaultFormatter = $name;
+	}
+
+/**
+ * Returns a new translator instance for the given name and locale
+ * based of conventions.
+ *
+ * @param string $name The translation package name.
+ * @param string $locale The locale to create the translator for.
+ * @return \Aura\Intl\Translator
+ */
+	protected function _fallbackLoader($name, $locale) {
+		$chain = new ChainMessagesLoader([
+			new MessagesFileLoader($name, $locale, 'mo'),
+			new MessagesFileLoader($name, $locale, 'po')
+		]);
+
+		// \Aura\Intl\Package by default uses formatter configured with key "basic".
+		// and we want to make sure the cake domain always uses the default formatter
+		$formatter = $name === 'cake' ? 'default' : $this->_defaultFormatter;
+		$chain = function() use ($formatter, $chain) {
+			$package = $chain();
+			$package->setFormatter($formatter);
+			return $package;
+		};
+
+		return $chain;
+	}
+
+/**
+ * Returns a function that can be used as a loader for the registerLoaderMethod
+ *
+ * @return callable
+ */
+	protected function _partialLoader() {
+		return function($name, $locale) {
+			return $this->_fallbackLoader($name, $locale);
+		};
+	}
+
+/**
  * Registers a new package by passing the register loaded function for the
  * package name.
  *
@@ -89,9 +157,26 @@ class TranslatorRegistry extends TranslatorLocator {
  * @return \Aura\Intl\TranslatorInterface A translator object.
  */
 	protected function _getFromLoader($name, $locale) {
-		$this->packages->set($name, $locale, function() use ($name, $locale) {
-			return $this->_loaders[$name]($name, $locale);
-		});
+		$loader = $this->_loaders[$name]($name, $locale);
+		$package = $loader;
+
+		if (!is_callable($loader)) {
+			$loader = function() use ($package) {
+				return $package;
+			};
+		}
+
+		if ($name !== 'default') {
+			$loader = function() use ($loader) {
+				$package = $loader();
+				if (!$package->getFallback()) {
+					$package->setFallback('default');
+				}
+				return $package;
+			};
+		}
+
+		$this->packages->set($name, $locale, $loader);
 		return parent::get($name, $locale);
 	}
 

tests/TestCase/I18n/I18nTest.php

@@ -299,6 +299,7 @@ class I18nTest extends TestCase {
 
 		$this->assertSame($english, I18n::translator());
 		$this->assertSame($spanish, I18n::translator('default', 'es_ES'));
+		$this->assertSame($english, I18n::translator());
 	}
 
 /**
@@ -347,4 +348,59 @@ class I18nTest extends TestCase {
 		$this->assertEquals('%d is 1 (po translated)', $translator->translate('%d = 1'));
 	}
 
+/**
+ * Tests that missing translations will get fallbacked to the default translator
+ *
+ * @return void
+ */
+	public function testFallbackTranslator() {
+		I18n::translator('default', 'fr_FR', function() {
+			$package = new Package('default');
+			$package->setMessages([
+				'Dog' => 'Le bark'
+			]);
+			return $package;
+		});
+
+		I18n::translator('custom', 'fr_FR', function() {
+			$package = new Package('default');
+			$package->setMessages([
+				'Cow' => 'Le moo'
+			]);
+			return $package;
+		});
+
+		$translator = I18n::translator('custom', 'fr_FR');
+		$this->assertEquals('Le moo', $translator->translate('Cow'));
+		$this->assertEquals('Le bark', $translator->translate('Dog'));
+	}
+
+/**
+ * Tests that it is possible to register a generic translators factory for a domain
+ * instead of having to create them manually
+ *
+ * @return void
+ */
+	public function testFallbackTranslatorWithFactory() {
+		I18n::translator('default', 'fr_FR', function() {
+			$package = new Package('default');
+			$package->setMessages([
+				'Dog' => 'Le bark'
+			]);
+			return $package;
+		});
+		I18n::config('custom', function($name, $locale) {
+			$this->assertEquals('custom', $name);
+			$package = new Package('default');
+			$package->setMessages([
+				'Cow' => 'Le moo',
+			]);
+			return $package;
+		});
+
+		$translator = I18n::translator('custom', 'fr_FR');
+		$this->assertEquals('Le moo', $translator->translate('Cow'));
+		$this->assertEquals('Le bark', $translator->translate('Dog'));
+	}
+
 }