nativeaudio

commit 3bdbe9d9e5d2e907bf64e2d33492e9a4e5648f9a
parent 87ea90df507740bf93d4cf2840953b0b38977098
Author: Jack Mordaunt <jackmordaunt.dev@gmail.com>
Date:   Thu, 17 Sep 2026 11:58:20 -0400

test: cover the ffmpeg fallbacks when ffmpeg is installed

FFmpegLoad, FFmpegDecode and FFmpegPlay had no tests, which is how a
mistyped ffplay flag shipped. They now run wherever ffmpeg is on PATH,
including Windows, so the fallback is checked without a Linux machine.
Load and Decode must agree exactly with each other and match the
ffmpeg-produced reference; FFmpegPlay must block for the file's duration.

Diffstat:
A
internal/test/ffmpeg_test.go
 | 
70
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 70 insertions(+), 0 deletions(-)
diff --git a/internal/test/ffmpeg_test.go b/internal/test/ffmpeg_test.go
@@ -0,0 +1,70 @@
+package test
+
+import (
+	"bytes"
+	"os/exec"
+	"testing"
+	"time"
+
+	"git.sr.ht/~jackmordaunt/nativeaudio"
+)
+
+// requireTools skips the test unless every named program is on PATH.
+func requireTools(t *testing.T, names ...string) {
+	t.Helper()
+	for _, n := range names {
+		if _, err := exec.LookPath(n); err != nil {
+			t.Skipf("%s not installed", n)
+		}
+	}
+}
+
+// TestFFmpegLoadAndDecode exercises the ffmpeg fallback on every
+// platform that has ffmpeg, regardless of which native decoder is in use.
+// The reference PCM was produced by ffmpeg, so output should match within
+// the same tolerance as the native decoders, and Load and Decode must
+// agree with each other exactly.
+func TestFFmpegLoadAndDecode(t *testing.T) {
+	requireTools(t, "ffmpeg", "ffprobe")
+	want := nativeaudio.Format{SampleRate: 44100, Channels: 2, BytesPerSample: 2}
+
+	loaded, f, err := nativeaudio.FFmpegLoad("compressed.m4a")
+	if err != nil {
+		t.Fatalf("FFmpegLoad: %v", err)
+	}
+	if f != want {
+		t.Fatalf("FFmpegLoad format: want %+v, got %+v", want, f)
+	}
+	if !bytes.Equal(loaded, uncompressed) && !equal(t, loaded, uncompressed) {
+		t.Fatal("FFmpegLoad output does not match reference")
+	}
+
+	decoded, f, err := nativeaudio.FFmpegDecode(compressed)
+	if err != nil {
+		t.Fatalf("FFmpegDecode: %v", err)
+	}
+	if f != want {
+		t.Fatalf("FFmpegDecode format: want %+v, got %+v", want, f)
+	}
+	if !bytes.Equal(decoded, loaded) {
+		t.Fatal("FFmpegDecode output differs from FFmpegLoad output for the same data")
+	}
+}
+
+// TestFFmpegPlay plays one second of silence through ffplay and checks
+// the call blocks for at least that long. A mistyped flag used to make
+// ffplay exit immediately with an error.
+func TestFFmpegPlay(t *testing.T) {
+	requireTools(t, "ffplay")
+	const seconds = 1
+	path := writeTemp(t, "silence.wav", silentWAV(44100, 2, seconds))
+	start := time.Now()
+	if err := nativeaudio.FFmpegPlay(path); err != nil {
+		t.Fatalf("FFmpegPlay: %v", err)
+	}
+	elapsed := time.Since(start)
+	t.Logf("ffplay took %v", elapsed.Round(time.Millisecond))
+	if min := time.Duration(seconds) * time.Second * 9 / 10; elapsed < min {
+		t.Errorf("FFmpegPlay returned after %v, want at least %v", elapsed, min)
+	}
+}