Adding Behavior to Map Multiple Keys at Once

src/Configuration.php

@@ -18,6 +18,11 @@ class Configuration
      */
     private $factory_mapper;
 
+    /**
+     * @var Mapper[]
+     */
+    private $mappers;
+
     /**
      * @param array              $config
      * @param string             $prefix
@@ -61,22 +66,24 @@ public function has($key)
     }
 
     /**
-     * Configures a Mapper object for the given Key
+     * Configures a Mapper object for the given Keys
      *
-     * The Mapper object can be configured
+     * The Mapper object can be configured externally by being returned and, as it is stored as a reference,
+     * will be shared across all "mapped" keys.
      *
-     * @param $key
+     * @param string[] $keys
      * @return Mapper
      *
      * @throws InvalidKeyException
      */
-    public function map($key)
+    public function map(...$keys)
     {
-        $this->checkKeyExists($key);
-
-        $mapper = $this->factory_mapper->createNew($this->config[$key]);
+        $mapper = $this->factory_mapper->createNew();
 
-        $this->config[$key] = $mapper;
+        array_walk($keys, function ($key) use ($mapper) {
+            $this->checkKeyExists($key);
+            $this->mappers[$key] = $mapper;
+        });
 
         return $mapper;
     }
@@ -95,8 +102,8 @@ public function get($key)
     {
         $this->checkKeyExists($key);
 
-        if ($this->config[$key] instanceof Mapper) {
-            return $this->config[$key]->map();
+        if (isset($this->mappers[$key])) {
+            return $this->mappers[$key]->map($this->config[$key]);
         }
 
         return $this->config[$key];

src/Configuration/Mapper.php

@@ -4,10 +4,6 @@
 
 class Mapper
 {
-    /**
-     * @var mixed
-     */
-    private $value;
 
     /**
      * @var mixed
@@ -20,28 +16,22 @@ class Mapper
     private $func;
 
     /**
-     * @param mixed $value
-     */
-    public function __construct($value)
-    {
-        $this->value = $value;
-    }
-
-    /**
+     * @param string $value
+     *
      * @return mixed
      */
-    public function map()
+    public function map($value)
     {
-        if ($this->cached !== null) {
-            return $this->cached;
+        if (isset($this->cached[$value])) {
+            return $this->cached[$value];
         }
 
         if ($this->func === null) {
-            return $this->cached = $this->value;
+            return $this->cached[$value] = $value;
         }
 
         $func = $this->func;
-        return $this->cached = $func($this->value);
+        return $this->cached[$value] = $func($value);
     }
 
     /**

src/Configuration/MapperFactory.php

@@ -42,8 +42,8 @@ public function __construct($mapper_class = Mapper::class)
      *
      * @return Mapper
      */
-    public function createNew($value)
+    public function createNew()
     {
-        return new $this->mapper_class($value);
+        return new $this->mapper_class();
     }
 }

tests/unit/Configuration/MapperFactoryTest.php

@@ -22,8 +22,7 @@ public function defaultMapperClass()
     {
         $sut = new MapperFactory();
 
-        self::assertInstanceOf(Mapper::class, $sut->createNew('value'));
-
+        self::assertInstanceOf(Mapper::class, $sut->createNew());
     }
 
     /**
@@ -34,7 +33,7 @@ public function injectedMapperClass()
     {
         $sut = new MapperFactory(ValidMapper::class);
 
-        self::assertInstanceOf(ValidMapper::class, $sut->createNew('value'));
+        self::assertInstanceOf(ValidMapper::class, $sut->createNew());
     }
 
     /**

tests/unit/Configuration/MapperTest.php

@@ -18,7 +18,7 @@ class MapperTest extends AbstractTestCase
      */
     public function returnOriginalValueIfNoFunction()
     {
-        self::assertSame('Original Value', (new Mapper('Original Value'))->map());
+        self::assertSame('Original Value', (new Mapper())->map('Original Value'));
     }
 
     /**
@@ -29,13 +29,13 @@ public function mappingValues()
         $original_value = 'baloney';
         $mapped_value   = 'YENOLAB';
 
-        $sut            = new Mapper($original_value);
+        $sut            = new Mapper();
 
         $sut->using(function ($value) {
             return strrev(strtoupper($value));
         });
 
-        self::assertSame($mapped_value, $sut->map());
+        self::assertSame($mapped_value, $sut->map($original_value));
     }
 
     /**
@@ -53,12 +53,12 @@ public function mappedValuesAreCached()
             ->with($original_value)
             ->willReturn($mapped_value);
 
-        $sut = new Mapper($original_value);
+        $sut = new Mapper();
 
         $sut->using($test_map);
 
-        self::assertSame($mapped_value, $sut->map());
-        self::assertSame($mapped_value, $sut->map());
+        self::assertSame($mapped_value, $sut->map($original_value));
+        self::assertSame($mapped_value, $sut->map($original_value));
     }
 
     /**
@@ -67,10 +67,10 @@ public function mappedValuesAreCached()
      */
     public function toInt($original, $expected)
     {
-        $sut = new Mapper($original);
+        $sut = new Mapper();
         $sut->toInt();
 
-        self::assertSame($expected, $sut->map());
+        self::assertSame($expected, $sut->map($original));
     }
 
     /**
@@ -79,10 +79,10 @@ public function toInt($original, $expected)
      */
     public function toBool($original, $expected)
     {
-        $sut = new Mapper($original);
+        $sut = new Mapper();
         $sut->toBool();
 
-        self::assertSame($expected, $sut->map());
+        self::assertSame($expected, $sut->map($original));
     }
 
     /**

tests/unit/ConfigurationTest.php

@@ -36,7 +36,6 @@ public function basicGets()
 
         self::assertSame('one', $sut_three->get('CFG_ONE'));
         self::assertSame('otherone', $sut_three->get('OTHER_ONE'));
-
     }
 
     /**
@@ -97,25 +96,33 @@ public function defaultMapper()
      */
     public function mappingValues()
     {
-        $factory        = $this->createMock(MapperFactory::class);
-        $mapper         = $this->createMock(Mapper::class);
-
-        $key            = 'BALONEY';
-        $original_value = 'Original Value';
-        $mapped_value   = 'Mapped Value';
+        $factory = $this->createMock(MapperFactory::class);
+        $mapper  = $this->createMock(Mapper::class);
 
         $factory
             ->method('createNew')
-            ->with($original_value)
             ->willReturn($mapper);
 
         $mapper
             ->method('map')
-            ->willReturn($mapped_value);
+            ->willReturnMap([
+                [ 'Original Value 1', 'Mapped Value 1' ],
+                [ 'Original Value 2', 'Mapped Value 2' ],
+                [ 'Original Value 3', 'Mapped Value 3' ],
+            ]);
+
+        $config = [
+            'KEY1' => 'Original Value 1',
+            'KEY2' => 'Original Value 2',
+            'KEY3' => 'Original Value 3',
+        ];
+
+        $sut = new Configuration($config, '', $factory);
 
-        $sut = new Configuration([$key => $original_value], '', $factory);
+        self::assertSame($mapper, $sut->map('KEY1', 'KEY2', 'KEY3'));
 
-        self::assertSame($mapper, $sut->map($key));
-        self::assertSame($mapped_value, $sut->get($key));
+        self::assertSame('Mapped Value 1', $sut->get('KEY1'));
+        self::assertSame('Mapped Value 2', $sut->get('KEY2'));
+        self::assertSame('Mapped Value 3', $sut->get('KEY3'));
     }
 }