1 files changed, 34 insertions, 5 deletions
diff --git a/cmd/krino/history_test.go b/cmd/krino/history_test.go
index ad7f6f6..6277e7b 100644
--- a/cmd/krino/history_test.go
+++ b/cmd/krino/history_test.go
@@ -5,7 +5,6 @@ package main
 import (
 	"bytes"
 	"context"
-	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
@@ -14,6 +13,7 @@ import (
 
 	"git.labunix.xyz/krino/internal/engine"
 	"git.labunix.xyz/krino/internal/journal"
+	"git.labunix.xyz/krino/internal/lock"
 )
 
 func TestLogListsRunsAndUndoReverses(t *testing.T) {
@@ -101,12 +101,13 @@ func TestUndoFailsImmediatelyWithHeldLock(t *testing.T) {
 	}
 
 	held := filepath.Join(h, ".local", "state", "krino", "dl.lock")
-	if err := os.MkdirAll(filepath.Dir(held), 0o755); err != nil {
-		t.Fatal(err)
-	}
-	if err := os.WriteFile(held, []byte(fmt.Sprintf("pid %d\n", os.Getpid())), 0o644); err != nil {
+	// A real lock, not a file that looks like one: the lock is the
+	// kernel's, so holding it means holding a descriptor.
+	l, err := lock.Acquire(context.Background(), held, false)
+	if err != nil {
 		t.Fatal(err)
 	}
+	defer l.Release()
 
 	code, out, errOut := runCLI(t, "undo", "-y")
 	if code != 1 || !strings.Contains(errOut, "another krino") {
@@ -560,3 +561,31 @@ func TestIgnoredGlobalFlagsAreRefused(t *testing.T) {
 		t.Errorf("log -n 3 (its own count flag) was refused: %d %q", code, errOut)
 	}
 }
+
+// TestWaitingForALockSaysSo: every run but -y waits for a held lock, which
+// the spec intends (§3, §11) - but waiting silently is indistinguishable
+// from a hang, and the wait has no timeout. A run about to wait must say
+// what it is waiting for before it blocks.
+func TestWaitingForALockSaysSo(t *testing.T) {
+	h := matchingFixture(t)
+	held := filepath.Join(h, ".local", "state", "krino", "dl.lock")
+	l, err := lock.Acquire(context.Background(), held, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	go func() {
+		time.Sleep(250 * time.Millisecond)
+		l.Release()
+	}()
+
+	code, _, errOut := runCLI(t, "-n")
+	if code != 0 {
+		t.Fatalf("dry run after the lock was released: %d %s", code, errOut)
+	}
+	if !strings.Contains(errOut, "waiting") {
+		t.Errorf("a run that waited for the lock said nothing about it:\n%q", errOut)
+	}
+	if !strings.Contains(errOut, held) {
+		t.Errorf("the notice does not name the lock file %q:\n%q", held, errOut)
+	}
+}