Merge pull request bocharsky-bw#25 from m1/exists-function

Add exists() method in order to check existence using callable function

Author: bocharsky-bw

README.md

@@ -61,6 +61,7 @@ $a = $a->shuffle(); // override instance you operates on, because $a !== $a->shu
     * [debug](#debug)
     * [diffWith](#diffwith)
     * [each](#each)
+    * [exists](#exists)
     * [export](#export)
     * [filter](#filter)
     * [find](#find)
@@ -402,6 +403,21 @@ $a = A::create(['a', 'b', 'c']);
 $a->each(); // [0 => 0, 'key' => 0, 1 => 'a', 'value' => 'a']
 ```
 
+### exists
+
+A custom contains function where you can supply your own contains function as a closure. 
+The closure must take two parameters, a needle and an element it will be comparing.
+
+``` php
+$a = A::create(['a', 'b', 'c']);
+
+$closure = function($needle, $element) {
+    return $needle === $element;
+};
+
+$a->exists($closure, 'a'); // true
+```
+
 ### export
 
 ``` php

src/AbstractArray.php

@@ -428,6 +428,25 @@ public function containsKey($key)
         return array_key_exists($key, $this->elements);
     }
 
+    /**
+     * Find the given value in the array using a closure
+     *
+     * @param callable $callable
+     * @param mixed $needle
+     *
+     * @return bool Returns true if the given value is found, false otherwise
+     */
+    public function exists(callable $callable, $needle)
+    {
+        foreach ($this->elements as $el) {
+            if ($callable($needle, $el)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     /**
      * Search for a given element and return the index of its first occurrence.
      *

tests/AbstractArrayTest.php

@@ -196,6 +196,25 @@ public function testEach(array $array)
         $this->assertSame($each, $arrayzy->each());
     }
 
+    /**
+     * @dataProvider simpleArrayProvider
+     *
+     * @param array $array
+     */
+    public function testExists(array $array)
+    {
+        $key = 2;
+
+        $closure = function($needle, $element){
+            return $needle === $element;
+        };
+
+        $arrayzy = $this->createArrayzy($array);
+        $isContains = in_array($key, $array);
+
+        $this->assertSame($isContains, $arrayzy->exists($closure, $key));
+    }
+
     /**
      * @dataProvider simpleArrayProvider
      *

tests/ImmutableArrayTest.php

@@ -850,4 +850,4 @@ public function testWalkRecursively(array $array)
 
         $this->assertImmutable($arrayzy, $resultArrayzy, $array, $resultArray);
     }
-}
+}

tests/MutableArrayTest.php

@@ -865,4 +865,4 @@ public function testWalkRecursively(array $array)
 
         $this->assertMutable($arrayzy, $resultArrayzy, $resultArray);
     }
-}
+}