Merge pull request #1 from emonkak/collection-combine

Add Collection::combine()

Author: emonkak

.travis.yml

@@ -12,11 +12,13 @@ cache:
     - $HOME/.composer/cache
 
 before_script:
-  - composer install
+  - composer install --prefer-source
 
 script:
   - mkdir -p build/logs
   - phpunit --coverage-clover build/logs/clover.xml
 
 after_script:
   - php vendor/bin/coveralls
+
+sudo: false

src/Collection.php

@@ -28,6 +28,19 @@ public static function from($source)
         return new Collection($source, self::$defaultProvider);
     }
 
+    public static function combine($sources)
+    {
+        if (!Iterators::isTraversable($sources)) {
+            $type = gettype($sources);
+            throw new \InvalidArgumentException("'$type' can not be traversable.");
+        }
+
+        return new Collection(
+            self::$defaultProvider->concat($sources),
+            self::$defaultProvider
+        );
+    }
+
     public static function range($start, $stop = null, $step = 1)
     {
         if ($stop === null) {

tests/AbstractCollectionTest.php

@@ -28,11 +28,38 @@ public function testFrom()
     /**
      * @expectedException \InvalidArgumentException
      */
-    public function testFromNotTraverableSource()
+    public function testFromThrowsInvalidArgumentException()
     {
         Collection::from(0);
     }
 
+    /**
+     * @dataProvider provideCombine
+     */
+    public function testCombine($sources, $expected)
+    {
+        $collection = Collection::combine($sources);
+
+        $this->assertSame($expected, $collection->toList());
+        $this->assertSame(Collection::getDefaultProvider(), $collection->getProvider());
+    }
+
+    public function provideCombine()
+    {
+        return [
+            [[], []],
+            [[new \ArrayIterator([1, 2]), [3, 4, 5]], [1, 2, 3, 4, 5]]
+        ];
+    }
+
+    /**
+     * @expectedException \InvalidArgumentException
+     */
+    public function testCombineThrowsInvalidArgumentException()
+    {
+        Collection::combine(1);
+    }
+
     public function tearDown()
     {
         Collection::setDefaultProvider($this->defaultProvider);
@@ -164,7 +191,7 @@ public function testParMap($factory)
      * @dataProvider provideCollectionFactory
      * @expectedException \InvalidArgumentException
      */
-    public function testParMapWhenWorkersAreZeroThrowException($factory)
+    public function testParMapThrowsInvalidArgumentException($factory)
     {
         $factory([])->parMap(function($x) { }, 0);
     }

tests/ArrayCollectionTest.php

@@ -10,15 +10,15 @@ class ArrayCollectionTest extends AbstractCollectionTest
     /**
      * @expectedException \OverflowException
      */
-    public function testRepeatOfInfiniteStream()
+    public function testRepeatThrowsOverflowException()
     {
         Collection::repeat('foo');
     }
 
     /**
      * @expectedException \OverflowException
      */
-    public function testIterate()
+    public function testIterateThrowsOverflowException()
     {
         Collection::iterate(2, function($x) { return $x * $x; });
     }
@@ -27,7 +27,7 @@ public function testIterate()
      * @dataProvider provideCollectionFactory
      * @expectedException \OverflowException
      */
-    public function testCycleOfInfiniteStream($factory)
+    public function testCycleThrowsOverflowException($factory)
     {
         $factory([1, 2])->cycle();
     }

tests/Selector/PropertySelectorParserTest.php

@@ -46,7 +46,7 @@ public function provideParse()
      * @dataProvider provideParseInvalidExpr
      * @expectedException \InvalidArgumentException
      */
-    public function testParseInvalidExpr($expr)
+    public function testParseThrowsInvalidArgumentException($expr)
     {
         PropertySelectorParser::parse($expr);
     }