Added the list of environment variable declared inside the 'env' file (#199)

Author: jclebreton

src/Dotenv.php

@@ -117,4 +117,14 @@ public function required($variable)
     {
         return new Validator((array) $variable, $this->loader);
     }
+
+    /**
+     * Get the list of environment variables declared inside the 'env' file.
+     *
+     * @return array
+     */
+    public function getEnvironmentVariableNames()
+    {
+        return $this->loader->variableNames;
+    }
 }

src/Loader.php

@@ -28,6 +28,13 @@ class Loader
      */
     protected $immutable;
 
+    /**
+     * The list of environment variables declared inside the 'env' file.
+     *
+     * @var array
+     */
+    public $variableNames = array();
+
     /**
      * Create a new loader instance.
      *
@@ -357,6 +364,8 @@ public function setEnvironmentVariable($name, $value = null)
     {
         list($name, $value) = $this->normaliseEnvironmentVariable($name, $value);
 
+        $this->variableNames[] = $name;
+
         // Don't overwrite existing environment variables if we're immutable
         // Ruby's dotenv does this with `ENV[key] ||= value`.
         if ($this->immutable && $this->getEnvironmentVariable($name) !== null) {

tests/Dotenv/DotenvTest.php

@@ -336,4 +336,12 @@ public function testDotenvRequiredCanBeUsedWithoutLoadingFile()
         $dotenv->required('REQUIRED_VAR')->notEmpty();
         $this->assertTrue(true);
     }
+
+    public function testGetEnvironmentVariablesList()
+    {
+        $dotenv = new Dotenv($this->fixturesFolder);
+        $dotenv->load();
+        $this->assertTrue(is_array($dotenv->getEnvironmentVariableNames()));
+        $this->assertSame(array('FOO', 'BAR', 'SPACED', 'NULL'), $dotenv->getEnvironmentVariableNames());
+    }
 }

tests/Dotenv/LoaderTest.php

@@ -97,6 +97,9 @@ public function testMutableLoaderClearsEnvironmentVars()
         $this->assertSame(false, getenv($this->key()));
         $this->assertSame(false, isset($_ENV[$this->key()]));
         $this->assertSame(false, isset($_SERVER[$this->key()]));
+        $this->assertTrue(is_array($this->mutableLoader->variableNames));
+        $this->assertFalse(empty($this->mutableLoader->variableNames));
+
     }
 
     public function testImmutableLoaderSetUnsetImmutable()
@@ -121,5 +124,7 @@ public function testImmutableLoaderCannotClearEnvironmentVars()
         $this->assertSame($this->value(), getenv($this->key()));
         $this->assertSame(true, isset($_ENV[$this->key()]));
         $this->assertSame(true, isset($_SERVER[$this->key()]));
+        $this->assertTrue(is_array($this->immutableLoader->variableNames));
+        $this->assertFalse(empty($this->immutableLoader->variableNames));
     }
 }