Merge remote-tracking branch 'lstrojny/feature/placeholder'

* lstrojny/feature/placeholder:
  Adding tests where parameter position matters
  Using annotations in tests
  Removing Util API
  Introduce function API
  Adding Util::placeholder() as alias for Util:…()
  Making placeholder create method static
  Removing leftover
  Placeholder implementation to replace abitrary arguments

Author: igorw

phpunit.xml.dist

@@ -22,4 +22,7 @@
             <directory>./src/</directory>
         </whitelist>
     </filter>
+    <php>
+        <ini name="error_reporting" value="-1"/>
+    </php>
 </phpunit>

src/React/Curry/Placeholder.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace React\Curry;
+
+final class Placeholder
+{
+    private static $instance;
+
+    private function __construct()
+    {
+    }
+
+    public static function create()
+    {
+        if (self::$instance === null) {
+            self::$instance = new self();
+        }
+
+        return self::$instance;
+    }
+
+    public function resolve(array &$args, $position)
+    {
+        if (count($args) === 0) {
+            throw new \InvalidArgumentException(
+                sprintf('Cannot resolve parameter placeholder at position %d. Parameter stack is empty', $position)
+            );
+        }
+
+        return array_shift($args);
+    }
+}

src/React/Curry/Util.php

@@ -6,6 +6,20 @@ final class Util
 {
     public static function bind(/*$fn, $args...*/)
     {
+        $args = func_get_args();
+        $fn = array_shift($args);
+
         return call_user_func_array('React\Curry\bind', func_get_args());
     }
+
+    public static function mergeParameters(array $left, array $right)
+    {
+        foreach ($left as $position => &$param) {
+            if ($param instanceof Placeholder) {
+                $param = $param->resolve($right, $position);
+            }
+        }
+
+        return array_merge($left, $right);
+    }
 }

src/React/Curry/functions.php

@@ -2,12 +2,24 @@
 
 namespace React\Curry;
 
+use React\Curry\Placeholder;
+
 function bind(/*$fn, $args...*/)
 {
     $args = func_get_args();
     $fn = array_shift($args);
 
     return function () use ($fn, $args) {
-        return call_user_func_array($fn, array_merge($args, func_get_args()));
+        return call_user_func_array($fn, Util::mergeParameters($args, func_get_args()));
     };
 }
+
+function …()
+{
+    return Placeholder::create();
+}
+
+function placeholder()
+{
+    return …();
+}

tests/React/Curry/BindTest.php

@@ -25,10 +25,62 @@ public function testBindWithTwoArgs()
         $this->assertSame(6, $addOneAndFive());
     }
 
+
+    public function testBindWithPlaceholder()
+    {
+        $add = $this->createAddFunction();
+        $addFun = bind($add, …(), 10);
+        $this->assertSame(20, $addFun(10));
+        $this->assertSame(30, $addFun(20));
+    }
+
+    public function testBindWithMultiplePlaceholders()
+    {
+        $prod = $this->createProdFunction();
+        $prodTwo = bind($prod, …(), 2, …());
+        $this->assertSame(4, $prodTwo(1, 2));
+        $this->assertSame(6, $prodTwo(1, 3));
+        $this->assertSame(8, $prodTwo(2, 2));
+        $this->assertSame(24, $prodTwo(3, 4));
+        $this->assertSame(48, $prodTwo(3, 8));
+    }
+
+    public function testPlaceholderParameterPosition()
+    {
+        $substr = bind('substr', …(), 0, …());
+        $this->assertSame('foo', $substr('foo', 3));
+        $this->assertSame('fo', $substr('foo', 2));
+        $this->assertSame('f', $substr('foo', 1));
+    }
+
+    /**
+     * @expectedException InvalidArgumentException
+     * @expectedExceptionMessage Cannot resolve parameter placeholder at position 0. Parameter stack is empty
+     */
+    public function testStringConversion()
+    {
+        $add = $this->createAddFunction();
+        $addTwo = bind($add, …(), 2);
+
+        $addTwo();
+    }
+
+    public function testAliasForUnicodePlaceholderFunction()
+    {
+        $this->assertSame(…(), placeholder());
+    }
+
     private function createAddFunction()
     {
         return function ($a, $b) {
             return $a + $b;
         };
     }
+
+    private function createProdFunction()
+    {
+        return function ($a, $b, $c) {
+            return $a * $b * $c;
+        };
+    }
 }