tokenCollection is immutable, way to remove token from collection

Author: Halleck45

src/Hal/Component/Token/TokenCollection.php

@@ -134,13 +134,43 @@ public function asArray() {
 
     /**
      * Replace token with another
-     * 
+     *
      * @param $index
      * @param Token $token
      * @return $this
      */
     public function replace($index, Token $token) {
-        $this->tokens[$index]  = $token;
-        return $this;
+        $tokens = $this->tokens;
+        $tokens[$index] = $token;
+        return new TokenCollection($tokens);
+    }
+
+    /**
+     * Remove part of tokens
+     *
+     * @param $index
+     * @param null $end
+     * @return TokenCollection
+     */
+    public function remove($index, $end = null)
+    {
+        $tokens = $this->tokens;
+        if (null === $end) {
+            $end = $index;
+        }
+        for ($i = $index; $i <= $end; $i++) {
+            unset($tokens[$i]);
+        }
+        return new TokenCollection(array_values($tokens));
+    }
+
+    /**
+     * Get token by its index
+     *
+     * @param $index
+     * @return null|Token
+     */
+    public function get($index) {
+        return isset($this->tokens[$index]) ? $this->tokens[$index] : null;
     }
 }

tests/Hal/Component/Token/TokenCollectionTest.php

@@ -0,0 +1,45 @@
+<?php
+namespace Test\Hal\Component\Token;
+
+use Hal\Component\Token\Token;
+use Hal\Component\Token\TokenCollection;
+
+/**
+ * @group token
+ */
+class TokenCollectionTest extends \PHPUnit_Framework_TestCase {
+
+
+    private $tokens;
+
+    public function __construct() {
+        $this->tokens = new TokenCollection(array(
+                array(T_STRING, 'a')
+            , array(T_STRING, 'b')
+            , array(T_STRING, 'c')
+        ));
+    }
+
+    public function testICanCountTokens() {
+       $this->assertEquals(3, sizeof($this->tokens, COUNT_NORMAL));
+    }
+
+    public function testTokenCollectionIsImmutable() {
+        $instance = $this->tokens->remove(0);
+        $this->assertFalse($instance === $this->tokens);
+
+        $instance = $this->tokens->replace(0, new Token(array(T_STRING, 'abc')));
+        $this->assertFalse($instance === $this->tokens);
+    }
+
+    public function testICanGetTokenByIndex() {
+        $this->assertInstanceOf('\Hal\Component\Token\Token', $this->tokens->get(0));
+    }
+
+    public function testICanExtractPartOfCollection() {
+        $instance = $this->tokens->extract(0, 2);
+        $this->assertEquals(2, $instance->count());
+        $this->assertFalse($instance === $this->tokens);
+
+    }
+}