Function TestExtractFileFromTar

pkg/fileutil/fileutil_test.go:583–632

(t *testing.T)

}

func TestExtractFileFromTar(t *testing.T) {
	// Helper to build an in-memory tar archive
	buildTar := func(files map[string][]byte) []byte {
		var buf bytes.Buffer
		tw := tar.NewWriter(&buf)
		for name, content := range files {
			hdr := &tar.Header{
				Name: name,
				Mode: 0600,
				Size: int64(len(content)),
			}
			if err := tw.WriteHeader(hdr); err != nil {
				t.Fatalf("buildTar: WriteHeader: %v", err)
			}
			if _, err := tw.Write(content); err != nil {
				t.Fatalf("buildTar: Write: %v", err)
			}
		}
		if err := tw.Close(); err != nil {
			t.Fatalf("buildTar: Close: %v", err)
		}
		return buf.Bytes()
	}

	t.Run("found file returns its content", func(t *testing.T) {
		want := []byte("hello from tar")
		archive := buildTar(map[string][]byte{"subdir/file.txt": want})

		got, err := ExtractFileFromTar(archive, "subdir/file.txt")
		require.NoError(t, err, "ExtractFileFromTar should succeed when file is present")
		assert.Equal(t, want, got, "Extracted content should match original")
	})

	t.Run("file not found returns error", func(t *testing.T) {
		archive := buildTar(map[string][]byte{"other.txt": []byte("data")})

		got, err := ExtractFileFromTar(archive, "missing.txt")
		require.Error(t, err, "ExtractFileFromTar should return error when file is absent")
		assert.Contains(t, err.Error(), "missing.txt", "Error should mention the missing filename")
		assert.Nil(t, got, "Result should be nil when file is not found")
	})

	t.Run("corrupted archive returns error", func(t *testing.T) {
		corrupted := []byte("this is not a valid tar archive")

		got, err := ExtractFileFromTar(corrupted, "any.txt")
		require.Error(t, err, "ExtractFileFromTar should return error for corrupted archive")
		assert.Nil(t, got, "Result should be nil for corrupted archive")
	})
}