Unit testing

grayscale_test.go

@@ -0,0 +1,32 @@
+package caire
+
+import (
+	"image"
+	"image/color"
+	"testing"
+)
+
+const ImgWidth = 10
+const ImgHeight = 10
+
+func TestGrayscale(t *testing.T) {
+	img := image.NewRGBA(image.Rect(0, 0, ImgWidth, ImgHeight))
+	for i := 0; i < img.Bounds().Dx(); i++ {
+		for j := 0; j < img.Bounds().Dy(); j++ {
+			img.Set(i, j, color.RGBA{177, 177, 177, 255})
+		}
+	}
+
+	for i := 0; i < img.Bounds().Dx(); i++ {
+		for j := 0; j < img.Bounds().Dy(); j++ {
+			r, g, b, _ := img.At(i, j).RGBA()
+			r = r >> 8
+			g = g >> 8
+			b = b >> 8
+
+			if r != g || r != b || g != b {
+				t.Errorf("R, G, B value expected to be equal. Got %v, %v, %v", r, g, b)
+			}
+		}
+	}
+}