tests: cover debug build missing mount result IDs

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

tests/debug.go

@@ -0,0 +1,131 @@
+package tests
+
+import (
+	"bytes"
+	"io"
+	"os/exec"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/containerd/continuity/fs/fstest"
+	"github.com/creack/pty"
+	"github.com/moby/buildkit/util/testutil/integration"
+	"github.com/stretchr/testify/require"
+)
+
+var debugTests = []func(t *testing.T, sb integration.Sandbox){
+	testDebugBuildMissingBindMountSource,
+}
+
+func testDebugBuildMissingBindMountSource(t *testing.T, sb integration.Sandbox) {
+	if !isExperimental() {
+		t.Skip("debug command is experimental")
+	}
+	if !isDockerWorker(sb) {
+		t.Skip("debug monitor test only needs a docker worker")
+	}
+
+	dockerfile := []byte(`
+FROM busybox:latest
+RUN --mount=type=bind,source=missing,target=/src true
+`)
+	dir := tmpdir(t,
+		fstest.CreateFile("Dockerfile", dockerfile, 0o600),
+	)
+
+	cmd := buildxCmd(sb, withArgs("debug", "--on=error", "build", "--progress=plain", "--output=type=cacheonly", dir))
+	f, err := pty.StartWithSize(cmd, &pty.Winsize{
+		Cols: 120,
+		Rows: 24,
+	})
+	require.NoError(t, err)
+	defer f.Close()
+
+	var output debugOutput
+	copyDone := make(chan struct{})
+	go func() {
+		_, _ = io.Copy(&output, f)
+		close(copyDone)
+	}()
+
+	waitCh := make(chan error, 1)
+	go func() {
+		waitCh <- cmd.Wait()
+	}()
+
+	exited, waitErr := waitForDebugPromptOrExit(t, &output, waitCh)
+	if !exited {
+		_, err = f.Write([]byte("exit\r"))
+		require.NoError(t, err)
+		waitErr = waitForDebugCommandExit(t, cmd, waitCh, &output)
+	}
+
+	_ = f.Close()
+	select {
+	case <-copyDone:
+	case <-time.After(time.Second):
+	}
+
+	out := output.String()
+	require.Error(t, waitErr, out)
+	require.Contains(t, out, "failed to calculate checksum")
+	require.Contains(t, out, "failed to create container")
+	require.NotContains(t, out, "panic:")
+	require.NotContains(t, out, "index out of range")
+}
+
+func waitForDebugPromptOrExit(t *testing.T, output *debugOutput, waitCh <-chan error) (bool, error) {
+	t.Helper()
+
+	timeout := time.NewTimer(time.Minute)
+	defer timeout.Stop()
+	ticker := time.NewTicker(100 * time.Millisecond)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case err := <-waitCh:
+			return true, err
+		case <-ticker.C:
+			if strings.Contains(output.String(), "(buildx) ") {
+				return false, nil
+			}
+		case <-timeout.C:
+			require.FailNow(t, "timeout waiting for debug monitor", output.String())
+		}
+	}
+}
+
+func waitForDebugCommandExit(t *testing.T, cmd *exec.Cmd, waitCh <-chan error, output *debugOutput) error {
+	t.Helper()
+
+	select {
+	case err := <-waitCh:
+		return err
+	case <-time.After(30 * time.Second):
+		if cmd.Process != nil {
+			_ = cmd.Process.Kill()
+		}
+		require.FailNow(t, "timeout waiting for debug command to exit", output.String())
+		return nil
+	}
+}
+
+type debugOutput struct {
+	mu  sync.Mutex
+	buf bytes.Buffer
+}
+
+func (b *debugOutput) Write(p []byte) (int, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.buf.Write(p)
+}
+
+func (b *debugOutput) String() string {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.buf.String()
+}