fix(template-function-uuid): use the current time when uuid.v6 has no timestamp (#647)

plugins/template-function-uuid/src/index.ts

@@ -61,7 +61,12 @@ export const plugin: PluginDefinition = {
         },
       ],
       async onRender(_ctx: Context, args: CallTemplateFunctionArgs): Promise<string | null> {
-        return v6({ msecs: new Date(String(args.values.timestamp)).getTime() });
+        // `timestamp` is optional, so an absent or unparseable value has to fall
+        // back to v6()'s own clock. Handing it NaN msecs is not a fallback: the
+        // uuid package masks NaN down to a zero timestamp (1582-10-15).
+        const timestamp = String(args.values.timestamp ?? "").trim();
+        const msecs = timestamp ? new Date(timestamp).getTime() : Number.NaN;
+        return Number.isNaN(msecs) ? v6() : v6({ msecs });
       },
     },
     {

plugins/template-function-uuid/tests/uuid.test.ts

@@ -0,0 +1,37 @@
+import type { Context } from "@yaakapp/api";
+import { describe, expect, it } from "vite-plus/test";
+import { plugin } from "../src";
+
+// A v6 UUID stores 60 bits of 100-nanosecond intervals since 1582-10-15 in its
+// first three groups, with the version nibble removed.
+function v6Millis(uuid: string): number {
+  const hex = uuid.replace(/-/g, "");
+  const intervals = BigInt(`0x${hex.slice(0, 12)}${hex.slice(13, 16)}`);
+  return Number(intervals / 10000n) - 12219292800000;
+}
+
+describe("uuid.v6", () => {
+  const v6 = plugin.templateFunctions?.find((f) => f.name === "uuid.v6");
+
+  it("uses the current time when no usable timestamp is given", async () => {
+    const inputs = [{}, { timestamp: "" }, { timestamp: null }, { timestamp: "not-a-date" }];
+    for (const values of inputs) {
+      const before = Date.now();
+      const result = await v6?.onRender({} as Context, { values, purpose: "send" });
+      const after = Date.now();
+
+      expect(result).not.toMatch(/^00000000-0000-6/);
+      const millis = v6Millis(result as string);
+      expect(millis).toBeGreaterThanOrEqual(before);
+      expect(millis).toBeLessThanOrEqual(after);
+    }
+  });
+
+  it("embeds a timestamp that is given", async () => {
+    const result = await v6?.onRender({} as Context, {
+      values: { timestamp: "2025-05-28T11:15:00Z" },
+      purpose: "send",
+    });
+    expect(v6Millis(result as string)).toBe(Date.parse("2025-05-28T11:15:00Z"));
+  });
+});