fm-rds-tx/internal/audio/wav_test.go

package audio

import (
    "os"
    "path/filepath"
    "testing"
)

func TestPCM16ToSample(t *testing.T) {
    if pcm16ToSample(32767) <= 0 {
        t.Fatal("expected positive sample")
    }
    if pcm16ToSample(-32768) < -1.0 {
        t.Fatal("expected clamped lower bound")
    }
}

func TestLoadWAVSource(t *testing.T) {
    dir := t.TempDir()
    path := filepath.Join(dir, "test.wav")
    wav := []byte{
        'R','I','F','F', 52,0,0,0, 'W','A','V','E',
        'f','m','t',' ', 16,0,0,0, 1,0, 1,0, 0x80,0xbb,0x00,0x00, 0x00,0x77,0x01,0x00, 2,0, 16,0,
        'd','a','t','a', 8,0,0,0,
        0,0, 255,127, 0,128, 0,0,
    }
    if err := os.WriteFile(path, wav, 0o644); err != nil {
        t.Fatalf("write wav: %v", err)
    }
    src, err := LoadWAVSource(path)
    if err != nil {
        t.Fatalf("LoadWAVSource failed: %v", err)
    }
    if src.SampleRate != 48000 {
        t.Fatalf("unexpected sample rate: %d", src.SampleRate)
    }
    if src.Channels != 1 {
        t.Fatalf("unexpected channels: %d", src.Channels)
    }
    _ = src.NextFrame()
}

func TestRejectInvalidWAV(t *testing.T) {
    dir := t.TempDir()
    path := filepath.Join(dir, "bad.wav")
    if err := os.WriteFile(path, []byte("nope"), 0o644); err != nil {
        t.Fatalf("write wav: %v", err)
    }
    if _, err := LoadWAVSource(path); err == nil {
        t.Fatal("expected wav load error")
    }
}