1 files changed, 55 insertions, 0 deletions
diff --git a/internal/post/post_test.go b/internal/post/post_test.go
new file mode 100644
index 0000000..7283afd
--- /dev/null
+++ b/internal/post/post_test.go
@@ -0,0 +1,55 @@
+package post
+
+import (
+	"testing"
+	"time"
+)
+
+func TestNewID(t *testing.T) {
+	t.Parallel()
+
+	loc := time.FixedZone("CET", 1*3600)
+	base := time.Date(2026, 4, 9, 14, 30, 22, 0, loc)
+
+	tests := []struct {
+		name   string
+		tm     time.Time
+		suffix int
+		want   string
+	}{
+		{
+			name:   "utc no suffix",
+			tm:     time.Date(2026, 4, 9, 14, 30, 22, 0, time.UTC),
+			suffix: 0,
+			want:   "2026-04-09-143022",
+		},
+		{
+			name:   "non utc converts to utc",
+			tm:     base,
+			suffix: 0,
+			want:   "2026-04-09-133022",
+		},
+		{
+			name:   "suffix one",
+			tm:     time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC),
+			suffix: 1,
+			want:   "2026-01-02-030405-1",
+		},
+		{
+			name:   "suffix large",
+			tm:     time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC),
+			suffix: 42,
+			want:   "2026-01-02-030405-42",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got := NewID(tt.tm, tt.suffix)
+			if got != tt.want {
+				t.Fatalf("NewID(%v, %d) = %q; want %q", tt.tm, tt.suffix, got, tt.want)
+			}
+		})
+	}
+}