Add getLanguages() and loaded models restrictions for static calls

- Add manual - Enforce tests
landrok · Sep 26, 2020 · af3df0b · af3df0b
1 parent 7be487f
commit af3df0b
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Showing 3 changed files with 108 additions and 20 deletions.
diff --git a/README.md b/README.md
@@ -17,12 +17,15 @@ Table of contents
 - [API Methods](#api-methods)
   - [evaluate()](#evaluate)
   - [getLanguage()](#getlanguage)
+  - [getLanguages()](#getLanguages)
   - [getScores()](#getscores)
   - [getSupportedLanguages()](#getsupportedlanguages)
   - [getText()](#gettext)
+  - [options](#options)
   - [For one-liners only](#for-one-liners-only)
 
 
+
 Features
 --------
 
@@ -32,7 +35,7 @@ Features
 - Learning steps are already done, library is ready to use
 - Small code, small footprint
 - N-grams algorithm
-- Supports PHP 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, 7.4 and HHVM
+- Supports PHP 5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, 7.4, 8.0 and HHVM
 
 
 Install
@@ -160,6 +163,19 @@ $detector->getLanguage(); // Returns 'en'
 ```
 ________________________________________________________________________
 
+#### getLanguages()
+
+__Type__ *array*
+
+A list of loaded models that will be evaluated.
+
+__Example__
+
+```php
+$detector->getLanguages(); // Returns something like ['de', 'en', 'fr']
+```
+________________________________________________________________________
+
 #### getScores()
 
 __Type__ *array*
@@ -222,6 +238,26 @@ $detector->getText();
 ```
 ________________________________________________________________________
 
+#### Options
+
+__Type__ *\LanguageDetector\LanguageDetector*
+
+For even better performance, loaded models can be specified explicitly.
+
+__Example__
+
+```php
+
+$text = 'My tailor is rich and Alison is in the kitchen with Bob.';
+
+$detector = new LanguageDetector(null, ['en', 'fr', 'de']);
+
+$language = $detector->evaluate($text);
+
+echo $language; // Prints something like 'en'
+```
+________________________________________________________________________
+
 #### For one-liners only
 
 __Type__ *\LanguageDetector\LanguageDetector*
@@ -260,5 +296,11 @@ print_r($detector->getSupportedLanguages());
 // The last evaluated string
 echo $detector->getText();
 
+// Limit loaded languages for even better performance
+echo LanguageDetector\LanguageDetector::detect(
+    'My tailor is rich and Alison is in the kitchen with Bob.',
+    ['en', 'de', 'fr', 'es']
+); // en
+
 ```
 ________________________________________________________________________
diff --git a/src/LanguageDetector/LanguageDetector.php b/src/LanguageDetector/LanguageDetector.php
@@ -16,7 +16,7 @@
 
 /**
  * LanguageDetector is the entry point for the detecting process.
- */ 
+ */
 class LanguageDetector
 {
     /**
@@ -41,25 +41,27 @@ class LanguageDetector
 
     /**
      * Configure all subset languages
-     * 
+     *
      * @param  string $dir A directory where subsets are.
      * @param  array $languages Language codes to load models for. By default, all languages are loaded.
      */
-    public function __construct($dir = null, $languages = null)
+    public function __construct($dir = null, array $languages = [])
     {
         $datadir = null === $dir
             ? __DIR__ . '/subsets' : rtrim($dir, '/');
 
         foreach (glob($datadir . '/*') as $file) {
-            if (! $languages || in_array(basename($file), $languages)) {
+            if (!count($languages)
+                || in_array(basename($file), $languages)
+            ) {
                 $this->languages[basename($file)] = new Language($file);
             }
         }
     }
 
     /**
      * Evaluates that a string matches a language
-     * 
+     *
      * @param  string $text
      * @return \LanguageDetector\LanguageDetector
      * @throws \InvalidArgumentException if $text is not a string
@@ -87,15 +89,25 @@ public function evaluate($text): self
 
     /**
      * Static call for oneliners
-     * 
+     *
      * @param  string $text
+     * @param  array $languages Language codes to load models for. By
+     *         default, all languages are loaded.
      * @return \LanguageDetector\LanguageDetector
      * @api
      */
-    public static function detect($text): self
+    public static function detect($text, array $languages = []): self
     {
-        if (is_null(self::$detector)) {
-            self::$detector = new self();
+        // All specified models have been loaded
+        $diff = count($languages)
+            ? array_diff(
+                        self::$detector->getLanguages(),
+                        $languages
+                    )
+            : [];
+
+        if (is_null(self::$detector) || count($diff)) {
+            self::$detector = new self(null, $languages);
         }
 
         return self::$detector->evaluate($text);
@@ -127,9 +139,20 @@ public function getLanguage($code = null): Language
         return $this->languages[$code];
     }
 
+   /**
+     * Get loaded languages
+     *
+     * @return []string An array of ISO codes
+     * @api
+     */
+    public function getLanguages(): array
+    {
+        return array_keys($this->languages);
+    }
+
     /**
      * Get all scored subsets
-     * 
+     *
      * @return array An array of ISO codes => scores
      * @throws \Exception if nothing has been evaluated
      * @api
@@ -145,7 +168,7 @@ public function getScores(): array
 
     /**
      * Get all supported languages
-     * 
+     *
      * @return array An array of ISO codes
      * @api
      */
@@ -156,7 +179,7 @@ public function getSupportedLanguages(): array
 
     /**
      * Get evaluated text
-     * 
+     *
      * @return string
      * @api
      */
@@ -167,7 +190,7 @@ public function getText(): string
 
     /**
      * Get best result when detector is used as a string
-     * 
+     *
      * @return string
      */
     public function __toString(): string
@@ -177,14 +200,14 @@ public function __toString(): string
 
     /**
      * Evaluate probabilities for one language
-     * 
+     *
      * @param  array $chunks
      * @return \Closure An evaluator
      */
     private function calculate(array $chunks): callable
     {
         return function($language, $code) use ($chunks) {
-            $this->scores[$code] = 
+            $this->scores[$code] =
                 array_sum(
                     array_intersect_key(
                         $language->getFreq(),
@@ -197,15 +220,15 @@ private function calculate(array $chunks): callable
 
     /**
      * Chunk a text
-     * 
+     *
      * @return array
      */
     private function chunk(): array
     {
         $chunks = [];
         $len = mb_strlen($this->text);
 
-        // Chunk sizes 
+        // Chunk sizes
         for ($i = 0; $i < 3; $i++) {
             for ($j = 0; $j < $len; $j++) {
                 if ($len > $j + $i) {

diff --git a/tests/LanguageDetector/LanguageSubsetTest.php b/tests/LanguageDetector/LanguageSubsetTest.php
@@ -3,6 +3,7 @@
 namespace LanguageDetectorTest;
 
 use LanguageDetector\Language;
+use LanguageDetector\LanguageDetector;
 use PHPUnit\Framework\TestCase;
 use InvalidArgumentException;
 
@@ -74,7 +75,7 @@ public function getLanguageSubsetScenarios()
 
     /**
      * Tests that subset are loaded
-     * 
+     *
      * @dataProvider getLanguageSubsetScenarios
      */
     public function testSubsetContents($code, $expected = null)
@@ -99,7 +100,7 @@ public function testSubsetContents($code, $expected = null)
 
     /**
      * Tests that getCode return s a valid code
-     * 
+     *
      * @dataProvider getLanguageSubsetScenarios
      */
     public function testSubsetGetCode($code, $expected = null)
@@ -126,4 +127,26 @@ public function testSubsetGetCode($code, $expected = null)
             (string)$language
         );
     }
+
+    /**
+     * Tests that a limited number of subsets has been loaded
+     */
+    public function testLimitLoadedSubsets()
+    {
+        $subsets = ['da', 'en', 'no', 'sv'];
+
+        $language = new LanguageDetector(null, $subsets);
+
+        $this->assertEquals(
+            $subsets,
+            $language->getLanguages()
+        );
+
+        $language = LanguageDetector::detect('ok', $subsets);
+
+        $this->assertEquals(
+            $subsets,
+            $language->getLanguages()
+        );
+    }
 }