100% test coverage

CoreGraphics.go

@@ -171,7 +171,7 @@ func extractImageData(img image.Image) imageData {
 			width:  bounds.Dx(),
 			height: bounds.Dy(),
 			colors: C.CGColorSpaceCreateDeviceGray(),
-			info:   C.CGBitmapInfo(C.kCGImageAlphaOnly),
+			info:   C.CGBitmapInfo(C.kCGImageAlphaNone),
 		}
 
 	case *image.Alpha16:
@@ -183,7 +183,7 @@ func extractImageData(img image.Image) imageData {
 			width:  bounds.Dx(),
 			height: bounds.Dy(),
 			colors: C.CGColorSpaceCreateDeviceGray(),
-			info:   C.CGBitmapInfo(C.kCGImageAlphaOnly),
+			info:   C.CGBitmapInfo(C.kCGImageAlphaNone),
 		}
 
 	case *image.Gray:

CoreGraphics_test.go

@@ -3,21 +3,33 @@
 package cocoa
 
 import (
+	"image"
 	"testing"
 
+	"image/color"
 	_ "image/png"
 )
 
 func TestCGImageCreate(t *testing.T) {
-	img := CGImageCreate(gopher)
-	CFRetain(CFTypeRef(img))
-	CFRelease(CFTypeRef(img))
-	CFRelease(CFTypeRef(img))
+	for _, test := range gopherImages {
+		img := CGImageCreate(test)
+		CFRetain(CFTypeRef(img))
+		CFRelease(CFTypeRef(img))
+		CFRelease(CFTypeRef(img))
+	}
 }
 
 func TestCGImageCreateNoCopy(t *testing.T) {
-	img := CGImageCreateNoCopy(gopher)
-	CFRetain(CFTypeRef(img))
-	CFRelease(CFTypeRef(img))
-	CFRelease(CFTypeRef(img))
+	for _, test := range gopherImages {
+		img := CGImageCreateNoCopy(test)
+		CFRetain(CFTypeRef(img))
+		CFRelease(CFTypeRef(img))
+		CFRelease(CFTypeRef(img))
+	}
+}
+
+func TestCGImageCreatePanic(t *testing.T) {
+	defer func() { recover() }()
+	CGImageCreate(image.NewUniform(color.Black))
+	t.Error("calling CGImageCreate with an unsupported image type did not panic!")
 }

image_test.go

@@ -5,28 +5,21 @@ package cocoa
 import (
 	"bufio"
 	"image"
+	"image/draw"
 	"os"
 	"testing"
 )
 
-var gopher image.Image
-
-func init() {
-	f, _ := os.Open("fixtures/gopher.png")
-	gopher, _, _ = image.Decode(bufio.NewReader(f))
-	f.Close()
-}
-
 func TestNewImage(t *testing.T) {
-	img := NewImage(gopher)
+	img := NewImage(gopherNRGBA)
 
 	if img.Ref() == nil {
 		t.Error("invalid nil image reference")
 	}
 }
 
 func TestNewImageWrap(t *testing.T) {
-	img1 := CGImageCreate(gopher)
+	img1 := CGImageCreate(gopherNRGBA)
 	img2 := NewImageWrap(img1)
 
 	if ref := img2.Ref(); ref != img1 {
@@ -35,10 +28,78 @@ func TestNewImageWrap(t *testing.T) {
 }
 
 func TestImageRelease(t *testing.T) {
-	img := NewImage(gopher)
+	img := NewImage(gopherNRGBA)
 	img.release()
 
 	if img.Ref() != nil {
 		t.Error("invalid non-nil image reference found after releasing")
 	}
 }
+
+func loadImage() image.Image {
+	f, _ := os.Open("fixtures/gopher.png")
+	i, _, _ := image.Decode(bufio.NewReader(f))
+	f.Close()
+	return i
+}
+
+func copyImage(dst draw.Image, src image.Image) image.Image {
+	draw.Draw(dst, dst.Bounds(), src, image.Point{}, draw.Over)
+	return dst
+}
+
+func imageToAlpha(img image.Image) image.Image {
+	return copyImage(image.NewAlpha(img.Bounds()), img)
+}
+
+func imageToAlpha16(img image.Image) image.Image {
+	return copyImage(image.NewAlpha16(img.Bounds()), img)
+}
+
+func imageToGray(img image.Image) image.Image {
+	return copyImage(image.NewGray(img.Bounds()), img)
+}
+
+func imageToGray16(img image.Image) image.Image {
+	return copyImage(image.NewGray16(img.Bounds()), img)
+}
+
+func imageToRGBA(img image.Image) image.Image {
+	return copyImage(image.NewRGBA(img.Bounds()), img)
+}
+
+func imageToRGBA64(img image.Image) image.Image {
+	return copyImage(image.NewRGBA64(img.Bounds()), img)
+}
+
+func imageToNRGBA64(img image.Image) image.Image {
+	return copyImage(image.NewNRGBA64(img.Bounds()), img)
+}
+
+func imageToCMYK(img image.Image) image.Image {
+	return copyImage(image.NewCMYK(img.Bounds()), img)
+}
+
+var (
+	gopherNRGBA   = loadImage()
+	gopherAlpha   = imageToAlpha(gopherNRGBA)
+	gopherAlpha16 = imageToAlpha16(gopherNRGBA)
+	gopherGray    = imageToGray(gopherNRGBA)
+	gopherGray16  = imageToGray16(gopherNRGBA)
+	gopherRGBA    = imageToRGBA(gopherNRGBA)
+	gopherRGBA64  = imageToRGBA64(gopherNRGBA)
+	gopherNRGBA64 = imageToNRGBA64(gopherNRGBA)
+	gopherCMYK    = imageToCMYK(gopherNRGBA)
+
+	gopherImages = [...]image.Image{
+		gopherNRGBA,
+		gopherAlpha,
+		gopherAlpha16,
+		gopherGray,
+		gopherGray16,
+		gopherRGBA,
+		gopherRGBA64,
+		gopherNRGBA64,
+		gopherCMYK,
+	}
+)