Merge pull request #12 from jmalloc/master

Implemented instanceBy and instanceByPredicate

Author: Erin Millard

src/Eloquent/Enumeration/Multiton.php

@@ -50,6 +50,41 @@ public static final function instanceByKey($key)
         throw new Exception\UndefinedInstanceException(get_called_class(), 'key', $key);
     }
 
+    /**
+     * Returns a single member instance by comparison with the result of an accessor method.
+     *
+     * @param string $property The name of the property (accessor method) to match.
+     * @param mixed $value The value to match.
+     *
+     * @return Multiton The first member instance for which $instance->{$property}() === $value.
+     * @throws UndefinedInstanceException If no associated instance is found.
+     */
+    public static final function instanceBy($property, $value) {
+        foreach (static::multitonInstances() as $instance) {
+            if ($instance->{$property}() === $value) {
+                return $instance;
+            }
+        }
+        throw new Exception\UndefinedInstanceException(get_called_class(), $property, $value);
+    }
+
+    /**
+     * Returns a single member instance by predicate callback.
+     *
+     * @param callback $predicate The predicate applies to the multiton instance to find a match.
+     *
+     * @return Multiton The first member instance for which $predicate($instance) evaluates to boolean true.
+     * @throws UndefinedInstanceException If no associated instance is found.
+     */
+    public static final function instanceByPredicate($predicate) {
+        foreach (static::multitonInstances() as $instance) {
+            if ($predicate($instance)) {
+                return $instance;
+            }
+        }
+        throw new Exception\UndefinedInstanceException(get_called_class(), '<callback>', '<callback>');
+    }
+
     /**
      * Maps static method calls to member instances.
      *

test/suite/Eloquent/Enumeration/MultitonTest.php

@@ -67,6 +67,72 @@ public function testInstanceByKeyFailureUndefined()
         ValidMultiton::instanceByKey('DOOM');
     }
 
+    public function testInstanceBy()
+    {
+        $this->assertSame(array(), ValidMultiton::calls());
+
+        $foo = ValidMultiton::instanceBy('key', 'FOO');
+        $bar = ValidMultiton::instanceBy('key', 'BAR');
+
+        $this->assertInstanceOf('Eloquent\Enumeration\Test\Fixture\ValidMultiton', $foo);
+        $this->assertInstanceOf('Eloquent\Enumeration\Test\Fixture\ValidMultiton', $bar);
+        $this->assertNotEquals($foo, $bar);
+        $this->assertSame($foo, ValidMultiton::instanceByKey('FOO'));
+        $this->assertSame($bar, ValidMultiton::instanceByKey('BAR'));
+
+        $this->assertSame(array(
+            array(
+                'Eloquent\Enumeration\Test\Fixture\ValidMultiton::initializeMultiton',
+                array(),
+            ),
+        ), ValidMultiton::calls());
+    }
+
+    public function testInstanceByFailureUndefined()
+    {
+        $this->setExpectedException('Eloquent\Enumeration\Exception\UndefinedInstanceException');
+        ValidMultiton::instanceBy('key', 'DOOM');
+    }
+
+    public function testInstanceByPredicate()
+    {
+        $this->assertSame(array(), ValidMultiton::calls());
+
+        $foo = ValidMultiton::instanceByPredicate(
+            function(ValidMultiton $instance) {
+                return $instance->key() === 'FOO';
+            }
+        );
+        $bar = ValidMultiton::instanceByPredicate(
+            function(ValidMultiton $instance) {
+                return $instance->key() === 'BAR';
+            }
+        );
+
+        $this->assertInstanceOf('Eloquent\Enumeration\Test\Fixture\ValidMultiton', $foo);
+        $this->assertInstanceOf('Eloquent\Enumeration\Test\Fixture\ValidMultiton', $bar);
+        $this->assertNotEquals($foo, $bar);
+        $this->assertSame($foo, ValidMultiton::instanceByKey('FOO'));
+        $this->assertSame($bar, ValidMultiton::instanceByKey('BAR'));
+
+        $this->assertSame(array(
+            array(
+                'Eloquent\Enumeration\Test\Fixture\ValidMultiton::initializeMultiton',
+                array(),
+            ),
+        ), ValidMultiton::calls());
+    }
+
+    public function testInstanceByPredicateFailureUndefined()
+    {
+        $this->setExpectedException('Eloquent\Enumeration\Exception\UndefinedInstanceException');
+        ValidMultiton::instanceByPredicate(
+            function(ValidMultiton $instance) {
+                return false;
+            }
+        );
+    }
+
     public function testCallStatic()
     {
         $foo = ValidMultiton::FOO();