audio: Add test for InifiniteLoop

audio/loop_test.go

@@ -0,0 +1,75 @@
+// Copyright 2018 The Ebiten Authors
+//
+// 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.
+
+package audio_test
+
+import (
+	"io"
+	"math"
+	"testing"
+
+	. "github.com/hajimehoshi/ebiten/audio"
+)
+
+func TestInfiniteLoop(t *testing.T) {
+	indexToByte := func(index int) byte {
+		return byte(math.Sin(float64(index)) * 256)
+	}
+
+	src := make([]byte, 256)
+	for i := range src {
+		src[i] = indexToByte(i)
+	}
+	l := NewInfiniteLoop(BytesReadSeekCloser(src), int64(len(src)))
+
+	buf := make([]byte, len(src)*4)
+	if _, err := io.ReadFull(l, buf); err != nil {
+		t.Error(err)
+	}
+	for i, b := range buf {
+		got := b
+		want := indexToByte(i % len(src))
+		if got != want {
+			t.Errorf("index: %d, got: %v, want: %v", i, got, want)
+		}
+	}
+
+	n, err := l.Seek(int64(len(src))*5+128, io.SeekStart)
+	if err != nil {
+		t.Error(err)
+	}
+	if want := int64(128); n != want {
+		t.Errorf("got: %v, want: %v", n, want)
+	}
+
+	n2, err := l.Seek(int64(len(src))*6+64, io.SeekCurrent)
+	if err != nil {
+		t.Error(err)
+	}
+	if want := int64(192); n2 != want {
+		t.Errorf("got: %v, want: %v", n, want)
+	}
+
+	buf2 := make([]byte, len(src)*7)
+	if _, err := io.ReadFull(l, buf2); err != nil {
+		t.Error(err)
+	}
+	for i, b := range buf2 {
+		got := b
+		want := indexToByte((i + 192) % len(src))
+		if got != want {
+			t.Errorf("index: %d, got: %v, want: %v", i, got, want)
+		}
+	}
+}