test(coverage): raise engine+agent coverage above 50%

internal/engine/stream_source_test.go

@@ -0,0 +1,90 @@
+package engine
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestParseBitrateKbps(t *testing.T) {
+	cases := []struct {
+		in   string
+		fb   int
+		want int
+	}{
+		{"", 5000, 5000},
+		{"192k", 0, 192},
+		{"192K", 0, 192},
+		{"5M", 0, 5000},
+		{"5m", 0, 5000},
+		{"4500", 0, 4500},
+		{"bogus", 100, 100},
+		{"0k", 100, 100},
+	}
+	for _, tc := range cases {
+		t.Run(tc.in, func(t *testing.T) {
+			if got := parseBitrateKbps(tc.in, tc.fb); got != tc.want {
+				t.Errorf("parseBitrateKbps(%q,%d) = %d, want %d", tc.in, tc.fb, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestEstimateOutputSize(t *testing.T) {
+	if got := estimateOutputSize(nil, TranscodeOpts{}); got != 0 {
+		t.Errorf("nil probe -> 0, got %d", got)
+	}
+	if got := estimateOutputSize(&StreamProbe{}, TranscodeOpts{}); got != 0 {
+		t.Errorf("zero duration -> 0, got %d", got)
+	}
+	probe := &StreamProbe{DurationSec: 60}
+	opts := TranscodeOpts{VideoBitrate: "5M", AudioBitrate: "192k"}
+	// (5000 + 192) * 1000 / 8 = 649_000 bytes/s; *60 = 38_940_000
+	got := estimateOutputSize(probe, opts)
+	if got != 38_940_000 {
+		t.Errorf("estimateOutputSize = %d, want 38_940_000", got)
+	}
+}
+
+func TestDiskFileSourceLifecycle(t *testing.T) {
+	tmp := t.TempDir()
+	path := filepath.Join(tmp, "movie.bin")
+	data := []byte("hello world")
+	if err := os.WriteFile(path, data, 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	src, err := newDiskFileSource(path)
+	if err != nil {
+		t.Fatalf("newDiskFileSource: %v", err)
+	}
+	defer src.Close()
+
+	if src.Size() != int64(len(data)) {
+		t.Errorf("Size = %d, want %d", src.Size(), len(data))
+	}
+	if src.EstimatedSize() != src.Size() {
+		t.Errorf("EstimatedSize should equal Size for disk source")
+	}
+	if !src.Final() {
+		t.Errorf("disk source should be Final")
+	}
+	if src.Transcoded() {
+		t.Errorf("disk source should not report Transcoded")
+	}
+	if src.FileName() != "movie.bin" {
+		t.Errorf("FileName = %q", src.FileName())
+	}
+
+	buf := make([]byte, 5)
+	n, err := src.ReadAt(buf, 6)
+	if err != nil || n != 5 || string(buf) != "world" {
+		t.Errorf("ReadAt = (%d,%v,%q), want (5,nil,'world')", n, err, buf)
+	}
+}
+
+func TestDiskFileSourceMissing(t *testing.T) {
+	if _, err := newDiskFileSource("/nonexistent/movie.bin"); err == nil {
+		t.Error("expected error opening nonexistent file")
+	}
+}