From 8edae211ff723b16bb9a143021a98921459b0b28 Mon Sep 17 00:00:00 2001
From: Jesse_Chen <chen.yue@mevixaga.com>
Date: Mon, 31 Aug 2026 04:29:38 +0800
Subject: [PATCH] test(billing): cover durable report settlement

---
 frontend/tests/personal-report-worker.test.ts | 99 +++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/frontend/tests/personal-report-worker.test.ts b/frontend/tests/personal-report-worker.test.ts
index 4e5e287a..8cab12ab 100644
--- a/frontend/tests/personal-report-worker.test.ts
+++ b/frontend/tests/personal-report-worker.test.ts
@@ -15,6 +15,7 @@ import {
   PersonalReportWorkerError,
   createPersonalReportWorker,
 } from "../src/lib/personal-report-worker-core.ts";
+import type { ReportBillingPort } from "../src/lib/personal-report-billing.ts";
 
 const USER_ID = "11111111-1111-4111-8111-111111111111";
 const REQUEST_ID = "22222222-2222-4222-8222-222222222222";
@@ -89,6 +90,7 @@ function createHarness(input: Readonly<{
   generate?: () => Promise<GeneratePersonalReportResult>;
   loseLeaseBeforeCompletion?: boolean;
   markReadyError?: PersonalReportJobServiceError;
+  billing?: ReportBillingPort;
 }>) {
   let job = input.job ?? jobRecord();
   let report = input.report === undefined ? reportRecord() : input.report;
@@ -97,6 +99,8 @@ function createHarness(input: Readonly<{
   let generateCount = 0;
   let completeCount = 0;
   let reportFailureCount = 0;
+  let billingCompleteCount = 0;
+  const billingReleaseReasons: string[] = [];
 
   function requireLease(jobId: string, leaseToken: string): PersonalReportJobRecord {
     assert.equal(jobId, job.id);
@@ -327,6 +331,19 @@ function createHarness(input: Readonly<{
       generateCount += 1;
       return input.generate?.() ?? { status: "ready", document: READY_DOCUMENT, evidenceHash: "c".repeat(64) };
     },
+    billing: input.billing
+      ? {
+          reserve: input.billing.reserve,
+          complete: async (completeInput: Parameters<ReportBillingPort["complete"]>[0]) => {
+            billingCompleteCount += 1;
+            return input.billing!.complete(completeInput);
+          },
+          release: async (releaseInput: Parameters<ReportBillingPort["release"]>[0]) => {
+            billingReleaseReasons.push(releaseInput.reason);
+            return input.billing!.release(releaseInput);
+          },
+        }
+      : undefined,
     now: () => NOW,
     retryDelayMs: () => 1_000,
     heartbeatIntervalMs: 60_000,
@@ -340,6 +357,8 @@ function createHarness(input: Readonly<{
     get generateCount() { return generateCount; },
     get completeCount() { return completeCount; },
     get reportFailureCount() { return reportFailureCount; },
+    get billingCompleteCount() { return billingCompleteCount; },
+    billingReleaseReasons,
   };
 }
 
@@ -537,6 +556,86 @@ test("retryable failures use the bounded job retry budget and fail the report on
   assert.equal(harness.reportFailureCount, 1);
 });
 
+test("successful durable generation completes the reserved report usage", async () => {
+  const billing: ReportBillingPort = {
+    async reserve() { throw new Error("not used"); },
+    async complete(input) {
+      assert.equal(input.userId, USER_ID);
+      assert.equal(input.requestId, REQUEST_ID);
+      assert.deepEqual(input.usage, {
+        actualModelId: "model-a",
+        modelConfigVersion: 7,
+        inputTokens: 120,
+        outputTokens: 45,
+        durationMs: 0,
+      });
+      return true;
+    },
+    async release() { throw new Error("release must not run"); },
+  };
+  const harness = createHarness({
+    billing,
+    generate: async () => ({
+      status: "ready",
+      document: READY_DOCUMENT,
+      evidenceHash: "c".repeat(64),
+      usage: { inputTokens: 120, outputTokens: 45, actualModelId: "model-a", modelConfigVersion: 7 },
+    }),
+  });
+
+  const result = await harness.worker.tick();
+
+  assert.equal(result.outcome, "ready");
+  assert.equal(harness.billingCompleteCount, 1);
+  assert.deepEqual(harness.billingReleaseReasons, []);
+});
+
+test("terminal durable generation failure releases the reserved report usage", async () => {
+  const billing: ReportBillingPort = {
+    async reserve() { throw new Error("not used"); },
+    async complete() { throw new Error("complete must not run"); },
+    async release(input) {
+      assert.equal(input.userId, USER_ID);
+      assert.equal(input.requestId, REQUEST_ID);
+      return true;
+    },
+  };
+  const harness = createHarness({
+    billing,
+    generate: async () => ({
+      status: "failed",
+      failureCode: "report_schema_invalid",
+      innerReason: "agent_output_invalid",
+    }),
+  });
+
+  const result = await harness.worker.tick();
+
+  assert.equal(result.outcome, "failed");
+  assert.deepEqual(harness.billingReleaseReasons, ["report_schema_invalid"]);
+  assert.equal(harness.billingCompleteCount, 0);
+});
+
+test("retryable durable generation failure does not release before retry exhaustion", async () => {
+  const billing: ReportBillingPort = {
+    async reserve() { throw new Error("not used"); },
+    async complete() { throw new Error("complete must not run"); },
+    async release() { return true; },
+  };
+  const harness = createHarness({
+    billing,
+    job: jobRecord({ maxAttempts: 2 }),
+    generate: async () => {
+      throw new PersonalReportWorkerError("calculation_unavailable", true);
+    },
+  });
+
+  const first = await harness.worker.tick();
+
+  assert.equal(first.outcome, "retry_scheduled");
+  assert.deepEqual(harness.billingReleaseReasons, []);
+});
+
 test("instrumentation retains the Skill guard and starts a singleton Node worker loop", () => {
   const instrumentation = readFileSync(new URL("../src/instrumentation.ts", import.meta.url), "utf8");
   const productionAdapter = readFileSync(new URL("../src/lib/personal-report-worker.ts", import.meta.url), "utf8");