CLI test coverage

internal/internal.go

@@ -7,6 +7,7 @@ import (
 	"regexp"
 	"strconv"
 	"syscall"
+	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
@@ -190,3 +191,30 @@ var (
 		Help: "The number of bytes used by replica operations",
 	}, []string{"replica_type", "operation"})
 )
+
+// TruncateDuration truncates d to the nearest major unit (s, ms, µs, ns).
+func TruncateDuration(d time.Duration) time.Duration {
+	if d < 0 {
+		if d < -10*time.Second {
+			return d.Truncate(time.Second)
+		} else if d < -time.Second {
+			return d.Truncate(time.Second / 10)
+		} else if d < -time.Millisecond {
+			return d.Truncate(time.Millisecond)
+		} else if d < -time.Microsecond {
+			return d.Truncate(time.Microsecond)
+		}
+		return d
+	}
+
+	if d > 10*time.Second {
+		return d.Truncate(time.Second)
+	} else if d > time.Second {
+		return d.Truncate(time.Second / 10)
+	} else if d > time.Millisecond {
+		return d.Truncate(time.Millisecond)
+	} else if d > time.Microsecond {
+		return d.Truncate(time.Microsecond)
+	}
+	return d
+}

internal/internal_test.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"reflect"
 	"testing"
+	"time"
 
 	"github.com/benbjohnson/litestream/internal"
 )
@@ -59,3 +60,41 @@ func TestParseWALSegmentPath(t *testing.T) {
 		})
 	}
 }
+
+func TestTruncateDuration(t *testing.T) {
+	for _, tt := range []struct {
+		input, output time.Duration
+	}{
+		{0, 0 * time.Nanosecond},
+
+		{1, 1 * time.Nanosecond},
+		{12, 12 * time.Nanosecond},
+		{123, 123 * time.Nanosecond},
+		{1234, 1 * time.Microsecond},
+		{12345, 12 * time.Microsecond},
+		{123456, 123 * time.Microsecond},
+		{1234567, 1 * time.Millisecond},
+		{12345678, 12 * time.Millisecond},
+		{123456789, 123 * time.Millisecond},
+		{1234567890, 1200 * time.Millisecond},
+		{12345678900, 12 * time.Second},
+
+		{-1, -1 * time.Nanosecond},
+		{-12, -12 * time.Nanosecond},
+		{-123, -123 * time.Nanosecond},
+		{-1234, -1 * time.Microsecond},
+		{-12345, -12 * time.Microsecond},
+		{-123456, -123 * time.Microsecond},
+		{-1234567, -1 * time.Millisecond},
+		{-12345678, -12 * time.Millisecond},
+		{-123456789, -123 * time.Millisecond},
+		{-1234567890, -1200 * time.Millisecond},
+		{-12345678900, -12 * time.Second},
+	} {
+		t.Run(fmt.Sprint(int(tt.input)), func(t *testing.T) {
+			if got, want := internal.TruncateDuration(tt.input), tt.output; got != want {
+				t.Fatalf("duration=%s, want %s", got, want)
+			}
+		})
+	}
+}

internal/testingutil/testingutil.go

@@ -0,0 +1,43 @@
+package testingutil
+
+import (
+	"os"
+	"testing"
+)
+
+// MustReadFile reads all data from filename. Fail on error.
+func MustReadFile(tb testing.TB, filename string) []byte {
+	tb.Helper()
+	b, err := os.ReadFile(filename)
+	if err != nil {
+		tb.Fatal(err)
+	}
+	return b
+}
+
+// Getpwd returns the working directory. Fail on error.
+func Getwd(tb testing.TB) string {
+	tb.Helper()
+
+	dir, err := os.Getwd()
+	if err != nil {
+		tb.Fatal(err)
+	}
+	return dir
+}
+
+// Setenv sets the environment variable key to value. The returned function reverts it.
+func Setenv(tb testing.TB, key, value string) func() {
+	tb.Helper()
+
+	prevValue := os.Getenv(key)
+	if err := os.Setenv(key, value); err != nil {
+		tb.Fatal(err)
+	}
+
+	return func() {
+		if err := os.Setenv(key, prevValue); err != nil {
+			tb.Fatal(tb)
+		}
+	}
+}