Rename examples/util to test/util

test/util/util.go

@@ -0,0 +1,80 @@
+// Package util contains utility code for demosntration of go-libwebp.
+package util
+
+import (
+	"bufio"
+	"image"
+	"image/png"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+// GetExFilePath returns the path of specified example file.
+func GetExFilePath(name string) string {
+	return filepath.Join(os.Getenv("GOPATH"), "src/github.com/harukasan/go-libwebp/examples/images", name)
+}
+
+// GetOutFilePath returns the path of specified out file.
+func GetOutFilePath(name string) string {
+	return filepath.Join(os.Getenv("GOPATH"), "src/github.com/harukasan/go-libwebp/examples/out", name)
+}
+
+// OpenFile opens specified example file
+func OpenFile(name string) (io io.Reader) {
+	io, err := os.Open(GetExFilePath(name))
+	if err != nil {
+		panic(err)
+	}
+	return
+}
+
+// ReadFile reads and returns data bytes of specified example file.
+func ReadFile(name string) (data []byte) {
+	data, err := ioutil.ReadFile(GetExFilePath(name))
+	if err != nil {
+		panic(err)
+	}
+	return
+}
+
+// CreateFile opens specified example file
+func CreateFile(name string) (f *os.File) {
+	f, err := os.Create(GetOutFilePath(name))
+	if err != nil {
+		panic(err)
+	}
+	return
+}
+
+// WritePNG encodes and writes image into PNG file.
+func WritePNG(img image.Image, name string) {
+	f, err := os.Create(GetOutFilePath(name))
+	if err != nil {
+		panic(err)
+	}
+	b := bufio.NewWriter(f)
+	defer func() {
+		b.Flush()
+		f.Close()
+	}()
+
+	if err := png.Encode(b, img); err != nil {
+		panic(err)
+	}
+	return
+}
+
+// ReadPNG reads and decodes png data into image.Image
+func ReadPNG(name string) (img image.Image) {
+	io, err := os.Open(GetExFilePath(name))
+	if err != nil {
+		panic(err)
+	}
+	img, err = png.Decode(io)
+	if err != nil {
+		panic(err)
+	}
+	return
+}