Made BaseArray class. Added OneOffArray.

Author: Sevavietl

README.md

@@ -11,6 +11,7 @@ Table of Contents
     - [4. offsetUnset](#composite-key-array-offset-unset)
 * [XPath Key Array](#xpath-key-array)
 * [Dotted Key Array](#dotted-key-array)
+* [One-off Array](#one-off-array)
 
 <a name="composite-key-array"></a>
 
@@ -176,4 +177,13 @@ Compared to `CompositeKeyArray`, `XPathKeyArray` has some limitations:
 Compared to `CompositeKeyArray`, `DottedKeyArray` has some limitations:
 
 1. You cannot use keys with `.` in them.
-2. You cannot use `null` as key. 
+2. You cannot use `null` as key.
+
+<a name="one-off-array"></a>
+
+## One-off Array
+
+Sometimes you want to get value from an array by key and `unset` this key after that. The `OneOffArray` class helps you with this.
+
+Again this class can be used in combination with `CompositeKeyArray` or its descendents: `XPathKeyArray` or `DottedKeyArray`.
+Actually, it can be used in combination with any object that implemets `ArrayAccess`.

src/BaseArray.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace Sevavietl\Arrays;
+
+class BaseArray implements \ArrayAccess
+{
+    protected $container;
+    protected $undefinedOffsetAction;
+
+    public function __construct($array = [])
+    {
+        $this->container = $array;
+
+        $this->validateContainerArrayOrArrayAccessObject();
+
+        $this->setUndefinedOffsetAction(function ($array, $offset) {
+            $offset = json_encode($offset);
+
+            throw new UndefinedOffsetException(
+                "Undefined offset $offset."
+            );
+        });
+    }
+
+    protected function validateContainerArrayOrArrayAccessObject()
+    {
+        if (is_array($this->container)) {
+            return;
+        }
+
+        if (
+            is_object($this->container)
+            && $this->container instanceof \ArrayAccess
+        ) {
+            return;
+        }
+
+        throw new \InvalidArgumentException;
+    }
+
+    public function setUndefinedOffsetAction(callable $callback)
+    {
+        $this->undefinedOffsetAction = $callback;
+
+        return $this;
+    }
+
+    public function offsetExists($offset) {
+        return isset($this->container[$offset]);
+    }
+
+    public function offsetGet($offset) {
+        if (isset($this->container[$offset])) {
+            return $this->container[$offset];
+        }
+
+        return $this->undefinedOffsetAction($this->container, $offset);
+    }
+
+    public function offsetSet($offset, $value) {
+        if (is_null($offset)) {
+            $this->container[] = $value;
+        } else {
+            $this->container[$offset] = $value;
+        }
+    }
+
+    public function offsetUnset($offset) {
+        unset($this->container[$offset]);
+    }
+}

src/CompositeKeyArray.php

@@ -2,34 +2,14 @@
 
 namespace Sevavietl\Arrays;
 
-class CompositeKeyArray implements \ArrayAccess
+class CompositeKeyArray extends BaseArray
 {
-    protected $array;
+    protected $container;
     protected $undefinedOffsetAction;
 
-    public function __construct(array $array = [])
-    {
-        $this->array = $array;
-
-        $this->undefinedOffsetAction = function ($array, $offset) {
-            $offset = json_encode($offset);
-
-            throw new UndefinedOffsetException(
-                "Undefined offset $offset."
-            );
-        };
-    }
-
-    public function setUndefinedOffsetAction(Callable $undefinedOffsetAction)
-    {
-        $this->undefinedOffsetAction = $undefinedOffsetAction;
-
-        return $this;
-    }
-
     public function toArray()
     {
-        return $this->array;
+        return $this->container;
     }
 
     protected $offsets;
@@ -39,7 +19,7 @@ public function offsetExists($offset)
         $this->setOffsets($offset);
 
         return $this->walkThroughOffsets(
-            $this->array,
+            $this->container,
             function ($array, $offset) {
                 return isset($array[$offset]);
             },
@@ -54,7 +34,7 @@ public function offsetGet($offset)
         $this->setOffsets($offset);
 
         return $this->walkThroughOffsets(
-            $this->array,
+            $this->container,
             function ($array, $offset) {
                 return $array[$offset];
             },
@@ -96,7 +76,7 @@ public function offsetSet($offset, $value)
         };
 
         return $this->walkThroughOffsets(
-            $this->array,
+            $this->container,
             $baseCaseAction,
             $offsetNotExistsAction
         );
@@ -107,7 +87,7 @@ public function offsetUnset($offset)
         $this->setOffsets($offset);
 
         return $this->walkThroughOffsets(
-            $this->array,
+            $this->container,
             function (&$array, $offset) {
                 unset($array[$offset]);
             },

src/OneOffArray.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Sevavietl\Arrays;
+
+class OneOffArray extends BaseArray
+{
+    public function offsetGet($offset)
+    {
+        $value = $this->container[$offset];
+        unset($this->container[$offset]);
+
+        return $value;
+    }
+}

tests/unit/BaseArrayTest.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace Sevavietl\Arrays\Tests\Unit;
+
+use Sevavietl\Arrays\BaseArray;
+
+class BaseArrayTest extends \TestCase
+{
+    /**
+     * @dataProvider instantiationDataProvider
+     */
+    public function testInstantiation($argument)
+    {
+        new BaseArray($argument);
+    }
+
+    public function instantiationDataProvider()
+    {
+        return [
+            [[1, 2, 3]],
+            [new \ArrayObject],
+        ];
+    }
+
+    /**
+     * @dataProvider instantiationThrowsExceptionDataProvider
+     *
+     * @expectedException InvalidArgumentException
+     */
+    public function testInstantiationThrowsException($argument)
+    {
+        new BaseArray($argument);
+    }
+
+    public function instantiationThrowsExceptionDataProvider()
+    {
+        return [
+            [1],
+            ['foo'],
+            [new \StdClass],
+        ];
+    }
+}

tests/unit/OneOffArrayTest.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Sevavietl\Arrays\Tests\Unit;
+
+use Sevavietl\Arrays\OneOffArray;
+use Sevavietl\Arrays\CompositeKeyArray;
+
+class OneOffArrayTest extends \TestCase
+{
+    /**
+     * @dataProvider arrayDataProviderForGetTesting
+     */
+    public function testOffsetGet($array, $offset, $value)
+    {
+        $array = new OneOffArray($array);
+
+        $this->assertEquals(
+            $value,
+            $array[$offset]
+        );
+        
+        $this->assertFalse(isset($array[$offset]));
+    }
+
+    public function arrayDataProviderForGetTesting()
+    {
+        return [
+            [[1], 0, 1],
+            [new CompositeKeyArray([1 => [2 => 3]]), ['1', '2'], 3],
+
+            [['foo' => 'bar'], 'foo', 'bar'],
+            [new CompositeKeyArray(['foo' => ['bar' => 'baz']]), ['foo', 'bar'], 'baz'],
+        ];
+    }
+}