test: Split util_test into readfile_test and readfile_js_test

exp/audio/audio.go

@@ -51,6 +51,7 @@ func (s *mixedPlayersStream) Read(b []byte) (int, error) {
 		return 0, nil
 	}
 
+	// TODO: This assumes that channelNum is a power of 2.
 	const mask = ^(channelNum*bytesPerSample - 1)
 	if len(s.context.players) == 0 {
 		l := min(len(b), x-s.writtenBytes)

readfile_js_test.go

@@ -12,15 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// +build js
+
 package ebiten_test
 
 import (
-	"bytes"
 	"encoding/base64"
 	"errors"
-	"github.com/gopherjs/gopherjs/js"
 	"io"
-	"io/ioutil"
 	"strings"
 )
 
@@ -106,19 +105,12 @@ SUVORK5CYII=`,
 }
 
 func readFile(path string) (io.Reader, error) {
-	if js.Global == nil {
-		b, err := ioutil.ReadFile(path)
-		if err != nil {
-			return nil, err
-		}
-		return bytes.NewBuffer(b), nil
-	}
 	// According to https://github.com/gopherjs/gopherjs/blob/master/doc/syscalls.md,
 	// syscall can be available on the unstable version of npm.
 	// Let's not use os package here.
 	str, ok := data[path]
 	if !ok {
-		return nil, errors.New("not found")
+		return nil, errors.New("ebiten_test: not found")
 	}
 	return base64.NewDecoder(base64.StdEncoding, strings.NewReader(str)), nil
 }

readfile_test.go

@@ -0,0 +1,31 @@
+// Copyright 2016 Hajime Hoshi
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !js
+
+package ebiten_test
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+)
+
+func readFile(path string) (io.Reader, error) {
+	b, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	return bytes.NewBuffer(b), nil
+}