Saving to TIFF should also fail

Signed-off-by: Yoan Blanc <yoan@dosimple.ch>

vips.go

@@ -8,6 +8,7 @@ import "C"
 
 import (
 	"errors"
+	"fmt"
 	"math"
 	"os"
 	"runtime"
@@ -370,21 +371,14 @@ func vipsSave(image *C.VipsImage, o vipsSaveOptions) ([]byte, error) {
 	switch o.Type {
 	case WEBP:
 		saveErr = C.vips_webpsave_bridge(tmpImage, &ptr, &length, 1, quality)
-		break
 	case PNG:
 		saveErr = C.vips_pngsave_bridge(tmpImage, &ptr, &length, 1, C.int(o.Compression), quality, interlace)
-		break
-	case GIF:
-		return nil, errors.New("VIPS cannot save to GIF")
-	case PDF:
-		return nil, errors.New("VIPS cannot save to PDF")
-	case SVG:
-		return nil, errors.New("VIPS cannot save to SVG")
-	case MAGICK:
-		return nil, errors.New("VIPS cannot save to MAGICK")
-	default:
+	case 0:
+		saveErr = C.vips_jpegsave_bridge(tmpImage, &ptr, &length, 1, quality, interlace)
+	case JPEG:
 		saveErr = C.vips_jpegsave_bridge(tmpImage, &ptr, &length, 1, quality, interlace)
-		break
+	default:
+		return nil, fmt.Errorf("VIPS cannot save to %v.", ImageTypes[o.Type])
 	}
 
 	if int(saveErr) != 0 {

vips_test.go

@@ -29,7 +29,7 @@ func TestVipsRead(t *testing.T) {
 }
 
 func TestVipsSave(t *testing.T) {
-	types := [...]ImageType{JPEG, PNG, TIFF, WEBP}
+	types := [...]ImageType{JPEG, PNG, WEBP}
 
 	for _, typ := range types {
 		image, _, _ := vipsRead(readImage("test.jpg"))
@@ -46,7 +46,7 @@ func TestVipsSave(t *testing.T) {
 }
 
 func TestVipsCannotSave(t *testing.T) {
-	types := [...]ImageType{GIF, PDF, SVG, MAGICK}
+	types := [...]ImageType{GIF, MAGICK, PDF, SVG, TIFF}
 
 	for _, typ := range types {
 		image, _, _ := vipsRead(readImage("test.jpg"))
@@ -118,9 +118,9 @@ func TestVipsWatermark(t *testing.T) {
 		t.Errorf("Cannot add watermark: %s", err)
 	}
 
-	buf, _ := vipsSave(newImg, vipsSaveOptions{Quality: 95})
-	if len(buf) == 0 {
-		t.Fatal("Empty image")
+	buf, err := vipsSave(newImg, vipsSaveOptions{Quality: 95})
+	if len(buf) == 0 || err != nil {
+		t.Fatalf("Empty image. %#v", err)
 	}
 }