internal/cli/check.go

@@ -11,6 +11,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/dustin/go-humanize"
@@ -163,7 +164,9 @@ func verifyRequiredSigner(
 }
 
 // reportCheckProgress renders progress updates until the channel closes.
-func reportCheckProgress(progress <-chan mfer.CheckStatus) {
+func reportCheckProgress(progress <-chan mfer.CheckStatus, wg *sync.WaitGroup) {
+	defer wg.Done()
+
 	for status := range progress {
 		if status.ETA > 0 {
 			log.Progressf("Checking: %d/%d files, %s/s, ETA %s, %d failures",
@@ -235,11 +238,17 @@ func runCheck(ctx *cli.Context, chk *mfer.Checker, showProgress bool) (int64, er
 	results := make(chan mfer.Result, 1)
 
 	// Set up progress channel
-	var progress chan mfer.CheckStatus
+	var (
+		progress   chan mfer.CheckStatus
+		progressWg sync.WaitGroup
+	)
+
 	if showProgress {
 		progress = make(chan mfer.CheckStatus, 1)
 
-		go reportCheckProgress(progress)
+		progressWg.Add(1)
+
+		go reportCheckProgress(progress, &progressWg)
 	}
 
 	// Process results in a goroutine
@@ -251,6 +260,9 @@ func runCheck(ctx *cli.Context, chk *mfer.Checker, showProgress bool) (int64, er
 
 	// Run check
 	err := chk.Check(ctx.Context, results, progress)
+
+	progressWg.Wait()
+
 	if err != nil {
 		return 0, fmt.Errorf("check failed: %w", err)
 	}

internal/cli/entry_test.go

@@ -13,6 +13,7 @@ import (
 	"strings"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/spf13/afero"
 	"github.com/stretchr/testify/assert"
@@ -393,6 +394,67 @@ func TestGenerateAndCheckCommand(t *testing.T) {
 	assert.Equal(t, 0, exitCode, "check failed: %s", testStderr(t, opts))
 }
 
+// sharedWriter appends to a buffer shared with other sharedWriters, so
+// output written to stdout and stderr is kept in the order it was written.
+// Each write first waits for delay.
+type sharedWriter struct {
+	mu    *sync.Mutex
+	buf   *bytes.Buffer
+	delay time.Duration
+}
+
+func (w sharedWriter) Write(p []byte) (int, error) {
+	time.Sleep(w.delay)
+
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	return w.buf.Write(p)
+}
+
+// TestCheckClearsProgressBeforeSummary asserts that check --progress writes
+// its last progress line and clears it before it logs the summary. Progress
+// writes are slowed down, so a progress goroutine that check did not wait for
+// would write after the summary, or after the run has returned.
+func TestCheckClearsProgressBeforeSummary(t *testing.T) {
+	t.Parallel()
+
+	fs := afero.NewMemMapFs()
+	require.NoError(t, fs.MkdirAll(testDir, 0o755))
+	writeTestFile(t, fs, testFile1, "hello world")
+
+	opts := testOpts([]string{testApp, cmdGenerate, "-q", "-o", testMF, testDir}, fs)
+	require.Equal(t, 0, runCLI(opts), "generate failed: %s", testStderr(t, opts))
+
+	var (
+		mu     sync.Mutex
+		output bytes.Buffer
+	)
+
+	opts = testOpts([]string{
+		testApp, cmdCheck, "--progress", testFlagBase, testDir, testMF,
+	}, fs)
+	opts.Stdout = sharedWriter{mu: &mu, buf: &output, delay: 100 * time.Millisecond}
+	opts.Stderr = sharedWriter{mu: &mu, buf: &output}
+	require.Equal(t, 0, runCLI(opts))
+
+	mu.Lock()
+	got := output.String()
+	mu.Unlock()
+
+	lastProgress := strings.Index(got, "Checking: 1/1 files")
+	progressDone := strings.Index(got, "\r\033[K")
+	summary := strings.Index(got, "checked 1 files")
+
+	require.NotEqual(t, -1, lastProgress, "no last progress line in %q", got)
+	require.NotEqual(t, -1, progressDone, "progress line never cleared in %q", got)
+	require.NotEqual(t, -1, summary, "no summary in %q", got)
+	assert.Less(t, lastProgress, progressDone,
+		"progress cleared before its last line in %q", got)
+	assert.Less(t, progressDone, summary,
+		"summary logged before progress was cleared in %q", got)
+}
+
 func TestCheckCommandWithMissingFile(t *testing.T) {
 	t.Parallel()