plural support

Gettext/Generators/PhpArray.php

@@ -32,6 +32,10 @@ static public function generate (Entries $entries, $string = false) {
 			)
 		);
 
+        if ($entries->getHeader('Plural-Forms') !== null) {
+            $translations[$domain]['']['plural-forms'] = $entries->getHeader('Plural-Forms');
+        }
+
 		$translations[$domain] = array_merge($translations[$domain], $array);
 
 		if ($string) {

Gettext/Translator.php

@@ -4,17 +4,34 @@
 class Translator {
 	static private $dictionary = array();
 	static private $domain = 'messages';
+	static private $pluralCount = 2;
+	static private $pluralCode = 'return ($n != 1);';
 	static private $context_glue = '\u0004';
 
 	public static function loadTranslations ($file) {
 		if (is_file($file)) {
 			$dictionary = include($file);
+			self::loadTranslationsArray($dictionary);
+		}
+	}
+
+	public static function loadTranslationsArray($dictionary)
+	{
+		if (is_array($dictionary)) {
+			$domain = isset($dictionary['messages']['']['domain']) ? $dictionary['messages']['']['domain'] : null;
 
-			if (is_array($dictionary)) {
-				$domain = isset($dictionary['messages']['']['domain']) ? $dictionary['messages']['']['domain'] : null;
-				unset($dictionary['messages']['']);
-				self::addTranslations($dictionary['messages'], $domain);
+			// If a plural form is set we extract those values
+			if (isset($dictionary['messages']['']['plural-forms'])) {
+				list($count, $code) = explode(';', $dictionary['messages']['']['plural-forms']);
+				self::$pluralCount = (int)str_replace('nplurals=','', $count);
+
+				// extract just the expression turn 'n' into a php variable '$n'.
+				// Slap on a return keyword and semicolon at the end.
+				self::$pluralCode = str_replace('plural=', 'return ', str_replace('n', '$n', $code)) . ';';
 			}
+
+			unset($dictionary['messages']['']);
+			self::addTranslations($dictionary['messages'], $domain);
 		}
 	}
 
@@ -85,7 +102,69 @@ public static function dnpgettext ($domain, $context, $original, $plural, $value
 		return ($key === 1) ? $original : $plural;
 	}
 
-	public static function isPlural ($n) {
-		return ($n === 1) ? 1 : 2;
+	/**
+	 * Executes the plural decision code given the number to decide which
+	 * plural version to take.
+	 *
+	 * @param $n
+	 * @return int
+	 */
+	public static function isPlural ($n)
+	{
+		$pluralFunc = create_function('$n', self::fixTerseIfs(self::$pluralCode));
+
+		if (self::$pluralCount <= 2) {
+			return ($pluralFunc($n)) ? 2 : 1;
+		} else {
+			// We need to +1 because while (GNU) gettext codes assume 0 based,
+			// this gettext actually stores 1 based.
+			return ($pluralFunc($n)) + 1;
+		}
+	}
+
+	/**
+	 * This function will recursively wrap failure states in brackets if they contain a nested terse if
+	 *
+	 * This because PHP can not handle nested terse if's unless they are wrapped in brackets.
+	 *
+	 * This code probably only works for the gettext plural decision codes.
+	 *
+	 * return ($n==1 ? 0 : $n%10>=2 && $n%10<=4 && ($n%100<10 || $n%100>=20) ? 1 : 2);
+	 * becomes
+	 * return ($n==1 ? 0 : ($n%10>=2 && $n%10<=4 && ($n%100<10 || $n%100>=20) ? 1 : 2));
+	 *
+	 * @param string $code    the terse if string
+	 * @param bool   $inner   If inner is true we wrap it in brackets
+	 * @return string         A formatted terse If that PHP can work with.
+	 */
+	public static function fixTerseIfs($code, $inner=false)
+	{
+		/**
+		 * (?P<expression>[^?]+)   Capture everything up to ? as 'expression'
+		 * \?                      ?
+		 * (?P<success>[^:]+)      Capture everything up to : as 'success'
+		 * :                       :
+		 * (?P<failure>[^;]+)      Capture everything up to ; as 'failure'
+		 */
+		preg_match('/(?P<expression>[^?]+)\?(?P<success>[^:]+):(?P<failure>[^;]+)/', $code, $matches);
+
+		// If no match was found then no terse if was present
+		if (!isset($matches[0]))
+			return $code;
+
+		$expression = $matches['expression'];
+		$success    = $matches['success'];
+		$failure    = $matches['failure'];
+
+		// Go look for another terse if in the failure state.
+		$failure = self::fixTerseIfs($failure, true);
+		$code = $expression . ' ? ' . $success . ' : ' . $failure;
+
+		if ($inner) {
+			return "($code)";
+		} else {
+			// note the semicolon. We need that for executing the code.
+			return "$code;";
+		}
 	}
 }

tests/GettextTest.php

@@ -1,6 +1,11 @@
 <?php
 include dirname(__DIR__).'/Gettext/autoloader.php';
 
+if (!function_exists('n__')) {
+    require_once(__DIR__ . '/../Gettext/translator_functions.php');
+}
+
+
 class GettextTest extends PHPUnit_Framework_TestCase {
 
 	public function testPhpCodeExtractor () {
@@ -12,6 +17,16 @@ public function testPhpCodeExtractor () {
 		return $entries;
 	}
 
+    public function testPoFileExtractor () {
+        $entries = Gettext\Extractors\Po::extract(__DIR__.'/files/gettext_plural.po');
+
+        $this->assertInstanceOf('Gettext\\Entries', $entries);
+
+        $pluralHeader = "nplurals=3; plural=(n==1 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2);";
+        $this->assertEquals($pluralHeader, $entries->getHeader('Plural-Forms'), "Plural form did not get extracted correctly");
+
+        return $entries;
+    }
 
 	/**
 	 * @depends testPhpCodeExtractor
@@ -126,4 +141,37 @@ public function testPhpArrayGenerator ($entries) {
 
 		unlink($filename);
 	}
+
+    /**
+     * @depends testPoFileExtractor
+     */
+    public function testMultiPlural ($entries) {
+
+        $translationArray = \Gettext\Generators\PhpArray::generate($entries);
+        \Gettext\Translator::loadTranslationsArray($translationArray);
+
+        /**
+         * Test that nplural=3 plural translation check comes up with the correct translation key.
+         */
+        $this->assertEquals('1 plik',      n__ ("one file", "multiple files", 1), "plural calculation result bad");
+        $this->assertEquals('2,3,4 pliki', n__ ("one file", "multiple files", 2), "plural calculation result bad");
+        $this->assertEquals('2,3,4 pliki', n__ ("one file", "multiple files", 3), "plural calculation result bad");
+        $this->assertEquals('2,3,4 pliki', n__ ("one file", "multiple files", 4), "plural calculation result bad");
+        $this->assertEquals('5-21 plików', n__ ("one file", "multiple files", 5), "plural calculation result bad");
+        $this->assertEquals('5-21 plików', n__ ("one file", "multiple files", 6), "plural calculation result bad");
+
+
+        /**
+         * Test that when less then the nplural translations are available it still works.
+         */
+        $this->assertEquals('1', n__ ("one", "more", 1), "non-plural fallback failed");
+        $this->assertEquals('*', n__ ("one", "more", 2), "non-plural fallback failed");
+        $this->assertEquals('*', n__ ("one", "more", 3), "non-plural fallback failed");
+
+        /**
+         * Test that non-plural translations the fallback still works.
+         */
+        $this->assertEquals('more', n__ ("single", "more", 3), "non-plural fallback failed");
+
+    }
 }

tests/files/gettext_plural.po

@@ -0,0 +1,19 @@
+msgid ""
+msgstr ""
+"Plural-Forms: nplurals=3; plural=(n==1 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2);\n"
+
+# Taken from http://www.gnu.org/savannah-checkouts/gnu/gettext/manual/html_node/Plural-forms.html
+msgid "one file"
+msgid_plural "multiple files"
+msgstr[0] "1 plik"
+msgstr[1] "2,3,4 pliki"
+msgstr[2] "5-21 plików"
+
+
+msgid "one"
+msgid_plural "more"
+msgstr[0] "1"
+msgstr[1] "*"
+
+msgid "single"
+msgstr "test"