Remove unused second part of the expiry counter

internal/server/pages.go

@@ -169,10 +169,16 @@ func describeExpiry(t *time.Time, now time.Time) string {
 	if t == nil {
 		return "never"
 	}
+	at := t.UTC().Format("2006-01-02 15:04 MST")
 	d := t.Sub(now).Round(time.Minute)
-	if d < 0 {
+	switch {
+	case d < 0:
 		return "expired"
+	case d == 0:
+		// Rounded away to nothing, and a zero duration is how this program
+		// spells "unlimited": saying "in never" of a file about to go would
+		// be exactly backwards.
+		return at + " (in under a minute)"
 	}
-	return fmt.Sprintf("%s (in %s)", t.UTC().Format("2006-01-02 15:04 MST"),
-		config.FormatDuration(d))
+	return fmt.Sprintf("%s (in %s)", at, config.FormatDuration(d))
 }

internal/server/server_test.go

@@ -1686,6 +1686,32 @@ func TestCustomNameFieldIsAlwaysUsable(t *testing.T) {
 	}
 }
 
+// The share page's expiry line is rounded to the minute, so it must not offer
+// a seconds tail it is not counting - nor, when the remainder rounds away to
+// nothing, claim the file is kept forever.
+func TestDescribeExpiryReadsAsWritten(t *testing.T) {
+	at := func(d time.Duration) *time.Time {
+		when := clock.Add(d)
+		return &when
+	}
+	for _, c := range []struct {
+		name string
+		in   *time.Time
+		want string
+	}{
+		{"no deadline", nil, "never"},
+		{"already gone", at(-time.Hour), "expired"},
+		{"about to go", at(20 * time.Second), "(in under a minute)"},
+		{"a minute off", at(time.Minute), "(in 1m)"},
+		{"an hour and a half", at(90 * time.Minute), "(in 1h30m)"},
+		{"three days", at(72 * time.Hour), "(in 3d)"},
+	} {
+		if got := describeExpiry(c.in, clock); !strings.Contains(got, c.want) {
+			t.Errorf("%s: describeExpiry = %q, want it to contain %q", c.name, got, c.want)
+		}
+	}
+}
+
 // A chosen passphrase has to work everywhere a generated token does: at the
 // login form, on an upload, and as a session.
 func TestChosenPassphraseWorksEndToEnd(t *testing.T) {