Implement a song struct to hold all the information of a single song (corresponding one .asm file) and Render function for it.

song/song_test.go

@@ -0,0 +1,64 @@
+package song_test
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io/ioutil"
+	"path"
+	"runtime"
+	"testing"
+
+	"github.com/vsariola/sointu/bridge"
+	"github.com/vsariola/sointu/song"
+)
+
+const BPM = 100
+const SAMPLE_RATE = 44100
+const TOTAL_ROWS = 16
+const SAMPLES_PER_ROW = SAMPLE_RATE * 4 * 60 / (BPM * 16)
+
+const su_max_samples = SAMPLES_PER_ROW * TOTAL_ROWS
+
+// const bufsize = su_max_samples * 2
+
+func TestSongRender(t *testing.T) {
+	patch := []bridge.Instrument{
+		bridge.Instrument{1, []bridge.Unit{
+			bridge.Unit{bridge.Envelope, []byte{32, 32, 64, 64, 128}},
+			bridge.Unit{bridge.Oscillat, []byte{64, 64, 0, 96, 64, 128, 0x40}},
+			bridge.Unit{bridge.Mulp, []byte{}},
+			bridge.Unit{bridge.Envelope, []byte{32, 32, 64, 64, 128}},
+			bridge.Unit{bridge.Oscillat, []byte{72, 64, 64, 64, 96, 128, 0x40}},
+			bridge.Unit{bridge.Mulp, []byte{}},
+			bridge.Unit{bridge.Out.Stereo(), []byte{128}},
+		}}}
+	patterns := [][]byte{{64, 0, 68, 0, 32, 0, 0, 0, 75, 0, 78, 0, 0, 0, 0, 0}}
+	tracks := []song.Track{song.Track{1, []byte{0}}}
+	song, err := song.NewSong(100, patterns, tracks, patch)
+	if err != nil {
+		t.Fatalf("NewSong failed: %v", err)
+	}
+	buffer, err := song.Render()
+	if err != nil {
+		t.Fatalf("Render failed: %v", err)
+	}
+	_, filename, _, _ := runtime.Caller(0)
+	expectedb, err := ioutil.ReadFile(path.Join(path.Dir(filename), "..", "tests", "expected_output", "test_oscillat_sine.raw"))
+	if err != nil {
+		t.Fatalf("cannot read expected: %v", err)
+	}
+	var createdbuf bytes.Buffer
+	err = binary.Write(&createdbuf, binary.LittleEndian, buffer)
+	if err != nil {
+		t.Fatalf("error converting buffer: %v", err)
+	}
+	createdb := createdbuf.Bytes()
+	if len(createdb) != len(expectedb) {
+		t.Fatalf("buffer length mismatch, got %v, expected %v", len(createdb), len(expectedb))
+	}
+	for i, v := range createdb {
+		if expectedb[i] != v {
+			t.Fatalf("byte mismatch @ %v, got %v, expected %v", i, v, expectedb[i])
+		}
+	}
+}