Merge pull request #2404 from cacaodev/CPArray-mapUsingBlock

New: CPArray -arrayByApplyingBlock:

Foundation/CPArray/_CPArray.j

@@ -880,6 +880,25 @@ Returns a hash for the object. Unlike Cocoa, the hash value does not take conten
     return join.call([self _javaScriptArrayCopy], aString);
 }
 
+/*!
+    Returns an Array formed by applying a function to the objects in the receiver.
+    @param aFunction a function taking two arguments: (element, index).
+    @return an Array containing the transformed elements.
+*/
+- (CPArray)arrayByApplyingBlock:(Function/*element, index*/)aFunction
+{
+	var result = [],
+	    count = [self count];
+
+	for (var idx = 0; idx < count; idx++)
+	{
+	    var obj = aFunction([self objectAtIndex:idx], idx);
+		[result addObject:obj];
+	}
+
+	return result;
+}
+
 // Creating a description of the array
 
 /*!

Foundation/CPArray/_CPJavaScriptArray.j

@@ -233,6 +233,19 @@ var concat = Array.prototype.concat,
     return join.call(self, aString);
 }
 
+- (CPArray)arrayByApplyingBlock:(Function/*element, index*/)aFunction
+{
+	var result = [];
+
+	for (var idx = 0; idx < self.length; idx++)
+	{
+	    var obj = aFunction(self[idx], idx);
+		result.push(obj);
+	}
+
+	return result;
+}
+
 - (void)insertObject:(id)anObject atIndex:(CPUInteger)anIndex
 {
     if (anIndex > self.length || anIndex < 0)
@@ -335,7 +348,6 @@ var concat = Array.prototype.concat,
         [super addObjectsFromArray:anArray];
 }
 
-
 - (id)copy
 {
     return slice.call(self, 0);

Tests/Foundation/CPArrayTest.j

@@ -705,6 +705,23 @@
   [self assert:[1, [CPNull null], "3"] equals:anArray];
 }
 
+- (void)testArrayByApplyingBlock
+{
+    var arr = @[@"a", @"b", @"c", @"d"];
+
+    var mapped = [arr arrayByApplyingBlock:function(obj, idx)
+    {
+        return obj + "_" + idx;
+    }];
+
+    [self assert:[mapped count] equals:[arr count]];
+
+    [arr enumerateObjectsUsingBlock:function(obj, idx, stop)
+    {
+        [self assert:mapped[idx] equals:(obj + "_" + idx)];
+    }];
+}
+
 @end
 
 @implementation AlwaysEqual : CPObject