av/stream/flac: saving progress

stream/flac/flac_test.go

@@ -38,45 +38,51 @@ const (
 	outFile  = "testOut.wav"
 )
 
+// TestWriteSeekerWrite checks that basic writing to the ws works as expected.
 func TestWriteSeekerWrite(t *testing.T) {
-	writerSeeker := &writeSeeker{}
-	var ws io.WriteSeeker = writerSeeker
+	ws := &writeSeeker{}
 
-	ws.Write([]byte("hello"))
-	if string(writerSeeker.buf) != "hello" {
-		t.Fail()
+	const tstStr1 = "hello"
+	ws.Write([]byte(tstStr1))
+	got := string(ws.buf)
+	if got != tstStr1 {
+		t.Errorf("Write failed, got: %v, want: %v", got, tstStr1)
 	}
 
-	ws.Write([]byte(" world"))
-	if string(writerSeeker.buf) != "hello world" {
-		t.Fail()
+	const tstStr2 = " world"
+	const want = "hello world"
+	ws.Write([]byte(tstStr2))
+	got = string(ws.buf)
+	if got != want {
+		t.Errorf("Second write failed, got: %v, want: %v", got, want)
 	}
-
 }
 
+// TestWriteSeekerSeek checks that writing and seeking works as expected, i.e. we
+// can write, then seek to a knew place in the buf, and write again, either replacing
+// bytes, or appending bytes.
 func TestWriteSeekerSeek(t *testing.T) {
-	writerSeeker := &writeSeeker{}
-	var ws io.WriteSeeker = writerSeeker
+	ws := &writeSeeker{}
 
 	ws.Write([]byte("hello"))
-	if string(writerSeeker.buf) != "hello" {
+	if string(ws.buf) != "hello" {
 		t.Fail()
 	}
 
 	ws.Write([]byte(" world"))
-	if string(writerSeeker.buf) != "hello world" {
+	if string(ws.buf) != "hello world" {
 		t.Fail()
 	}
 
 	ws.Seek(-2, io.SeekEnd)
 	ws.Write([]byte("k!"))
-	if string(writerSeeker.buf) != "hello work!" {
+	if string(ws.buf) != "hello work!" {
 		t.Fail()
 	}
 
 	ws.Seek(6, io.SeekStart)
 	ws.Write([]byte("gopher"))
-	if string(writerSeeker.buf) != "hello gopher" {
+	if string(ws.buf) != "hello gopher" {
 		t.Fail()
 	}
 }