Initial commit

packages/core-audit/src/with-audit.test.ts

@@ -0,0 +1,53 @@
+import { describe, it, expect, expectTypeOf, vi } from "vitest";
+import { withAudit, type Audited } from "@/with-audit";
+import type { IAuditLog } from "@/audit-log.interface";
+import { isAudited } from "@repo/core-shared/conformance";
+
+function makeAuditLog(): IAuditLog {
+  return {
+    record: vi.fn().mockResolvedValue(undefined),
+    eraseSubject: vi.fn().mockResolvedValue(undefined),
+  };
+}
+
+describe("withAudit", () => {
+  it("returns an Audited<F>", () => {
+    const auditLog = makeAuditLog();
+    const fn = async (_input: { id: string }) => ({ ok: true });
+    const wrapped = withAudit(auditLog, fn);
+    expectTypeOf(wrapped).toMatchTypeOf<Audited<typeof fn>>();
+  });
+
+  it("attaches __audited as a non-enumerable property on the wrapped function", () => {
+    const auditLog = makeAuditLog();
+    const fn = async () => ({ ok: true });
+    const wrapped = withAudit(auditLog, fn);
+    expect(isAudited(wrapped)).toBe(true);
+    expect(Object.keys(wrapped)).not.toContain("__audited");
+  });
+
+  it("does NOT pollute the original input function with the brand", () => {
+    const auditLog = makeAuditLog();
+    const fn = async () => ({ ok: true });
+    const wrapped = withAudit(auditLog, fn);
+    expect(isAudited(fn)).toBe(false);
+    expect(wrapped).not.toBe(fn);
+  });
+
+  it("passes input and output through unchanged", async () => {
+    const auditLog = makeAuditLog();
+    const fn = async (input: { id: string }) => ({ ok: true, id: input.id });
+    const wrapped = withAudit(auditLog, fn);
+    const result = await wrapped({ id: "abc" });
+    expect(result).toEqual({ ok: true, id: "abc" });
+  });
+
+  it("propagates errors", async () => {
+    const auditLog = makeAuditLog();
+    const err = new Error("boom");
+    const wrapped = withAudit(auditLog, async () => {
+      throw err;
+    });
+    await expect(wrapped()).rejects.toBe(err);
+  });
+});