package tga_test import (	"github.com/ftrvxmtrx/tga"	"image"	"image/draw"	"os"	"testing") const dstFilename = "encode_test.tga" func encode(m image.Image) (err error) {	var f *os.File 	if f, err = os.Create("testdata/" + dstFilename); err != nil {		return	} 	defer f.Close()	err = tga.Encode(f, m) 	return} func testImagesEqual(filename string, expected, got image.Image, t *testing.T) bool {	gb := expected.Bounds() 	for x := gb.Min.X; x < gb.Max.X; x++ {		for y := gb.Min.Y; y < gb.Max.Y; y++ {			if !equal(expected.At(x, y), got.At(x, y)) {				t.Errorf("%s: (%d, %d) -- expected %v, got %v", filename, x, y, expected.At(x, y), got.At(x, y))				return false			}		}	} 	return true} func TestEncode(t *testing.T) {	defer os.Remove("testdata/" + dstFilename) loop: 	for _, test := range tgaTests {		typ := "normal" 		if m, _, err := decode(test.source); err != nil {			t.Errorf("%s: %v", test.source, err)		} else if err = encode(m); err != nil {			t.Errorf("%s: encode failed (%v)", test.source, err)		} else if second, _, err := decode(dstFilename); err != nil {			t.Errorf("%s: %v", dstFilename, err)		} else if testImagesEqual(test.source, m, second, t) {			// test monochrome			b := second.Bounds()			gray := image.NewGray(b)			draw.Draw(gray, b, second, b.Min, draw.Src)			typ = "gray" 			if err = encode(gray); err != nil {				t.Errorf("%s: encode to gray failed (%v)", test.source, err)			} else if third, _, err := decode(dstFilename); err != nil {				t.Errorf("%s: gray decode failed (%v)", dstFilename, err)			} else if testImagesEqual(test.source, gray, third, t) {				premultiplied := image.NewRGBA(b)				draw.Draw(premultiplied, b, second, b.Min, draw.Src)				typ = "premultiplied" 				if err = encode(premultiplied); err != nil {					t.Errorf("%s: encode to premultiplied failed (%v)", test.source, err)				} else if fourth, _, err := decode(dstFilename); err != nil {					t.Errorf("%s: premultiplied decode failed (%v)", dstFilename, err)				} else if testImagesEqual(test.source, premultiplied, fourth, t) {					continue loop				} else {					t.Errorf("%T %T", premultiplied, fourth)				}			}		} 		t.Errorf("%s: encoded %s image (%s) is different", test.source, typ, dstFilename)	}}