1 files changed, 89 insertions, 0 deletions
diff --git a/UnitTesting/GTMCALayer+UnitTesting.m b/UnitTesting/GTMCALayer+UnitTesting.m
new file mode 100644
index 0000000..355f956
--- /dev/null
+++ b/UnitTesting/GTMCALayer+UnitTesting.m
@@ -0,0 +1,89 @@
+//
+//  GTMCALayer+UnitTesting.m
+//  
+//  Category for making unit testing of graphics/UI easier.
+//  Allows you to save a view out to a image file, and compare a view
+//  with a previously stored representation to make sure it hasn't changed.
+//
+//  Copyright 2006-2008 Google Inc.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+//  use this file except in compliance with the License.  You may obtain a copy
+//  of the License at
+// 
+//  http://www.apache.org/licenses/LICENSE-2.0
+// 
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+//  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+//  License for the specific language governing permissions and limitations under
+//  the License.
+//
+
+#import "GTMCALayer+UnitTesting.h"
+
+@implementation CALayer (GTMUnitTestingAdditions) 
+
+//  Returns an image containing a representation of the object
+//  suitable for use in comparing against a master image.
+//  NB this means that all colors should be from "NSDevice" color space
+//  Does all of it's drawing with smoothfonts and antialiasing off
+//  to avoid issues with font smoothing settings and antialias differences
+//  between ppc and x86.
+//
+//  Returns:
+//    an image of the object
+- (CGImageRef)gtm_createUnitTestImage {
+  CGRect bounds = [self bounds];
+  CGSize size = CGSizeMake(CGRectGetWidth(bounds), CGRectGetHeight(bounds));
+  CGContextRef context = [self gtm_createUnitTestBitmapContextOfSize:size
+                                                                data:NULL];
+  _GTMDevAssert(context, @"Couldn't create context");
+  
+  // iPhone renders are flipped
+  CGAffineTransform transform = CGAffineTransformMakeTranslation(0, size.height);
+  transform = CGAffineTransformScale(transform, 1.0, -1.0);
+  CGContextConcatCTM(context, transform);
+  
+  [self renderInContext:context];
+  CGImageRef image = CGBitmapContextCreateImage(context);
+  CFRelease(context);
+  return image;
+}
+
+//  Encodes the state of an object in a manner suitable for comparing
+//  against a master state file so we can determine whether the
+//  object is in a suitable state.
+//
+//  Arguments:
+//    inCoder - the coder to encode our state into
+- (void)gtm_unitTestEncodeState:(NSCoder*)inCoder {
+  [super gtm_unitTestEncodeState:inCoder];
+  [inCoder encodeBool:[self isHidden] forKey:@"LayerIsHidden"];
+  [inCoder encodeBool:[self isDoubleSided] forKey:@"LayerIsDoublesided"];
+  [inCoder encodeBool:[self isOpaque] forKey:@"LayerIsOpaque"];
+  [inCoder encodeFloat:[self opacity] forKey:@"LayerOpacity"];
+  // TODO: There is a ton more we can add here. What are we interested in?
+  if ([self gtm_shouldEncodeStateForSublayers]) {
+    int i = 0;
+    for (CALayer *subLayer in [self sublayers]) {
+      [inCoder encodeObject:subLayer 
+                     forKey:[NSString stringWithFormat:@"CALayerSubLayer %d", i]];
+      i = i + 1;
+    }
+  }
+}
+
+//  Returns whether gtm_unitTestEncodeState should recurse into sublayers
+//
+//  Returns:
+//    should gtm_unitTestEncodeState pick up sublayer state.
+- (BOOL)gtm_shouldEncodeStateForSublayers {
+  BOOL value = YES;
+  if([self.delegate respondsToSelector:@selector(gtm_shouldEncodeStateForSublayersOfLayer:)]) {
+    value = [self.delegate gtm_shouldEncodeStateForSublayersOfLayer:self];
+  }
+  return value;
+}
+
+@end