plan 9: the log restores a missing final newline

1 files changed, 27 insertions, 0 deletions

diff --git a/internal/journal/journal_test.go b/internal/journal/journal_test.go
index a95bb05..e8b18ae 100644
--- a/internal/journal/journal_test.go
+++ b/internal/journal/journal_test.go
@@ -148,3 +148,30 @@ func TestAppendIsAppendOnly(t *testing.T) {
 		t.Errorf("%d lines after two Open/Append/Close cycles, want 2: the second Open truncated", got)
 	}
 }
+
+// TestOpenRepairsAMissingFinalNewline: a crash can leave the log's last
+// line without its newline; the next run's first line must not be glued
+// onto it, or that run could never be undone (review M8).
+func TestOpenRepairsAMissingFinalNewline(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "krino.log")
+	if err := os.WriteFile(path, []byte("2026-09-11T10:02:03+02:00\tR0\tdl\ta.pdf\t1\tmo"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	w, err := Open(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	at := time.Date(2026, 9, 11, 10, 5, 0, 0, time.UTC)
+	for _, e := range []Entry{{Time: at, Run: "R1", Action: "run-start", Status: "ok"}, {Time: at, Run: "R1", Action: "run-end", Status: "ok"}} {
+		if err := w.Append(e); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := w.Close(); err != nil {
+		t.Fatal(err)
+	}
+	entries, err := Entries(path, "R1")
+	if err != nil || len(entries) != 2 {
+		t.Fatalf("Entries(R1) = %d entries, %v; want run-start and run-end", len(entries), err)
+	}
+}