test(unit): add lightweight vitest coverage for auth duration and seq pagination utils

Fabric.Backend.Guild/src/messaging/messaging.controller.ts

@@ -17,6 +17,7 @@ import { Channel } from '../entities/channel.entity';
 import { Message } from '../entities/message.entity';
 import { IdempotencyRecord } from '../entities/idempotency-record.entity';
 import { EventsService } from '../events/events.service';
+import { clampLimit, computeNextExpectedSeq } from './pagination.util';
 
 const EDIT_WINDOW_MS = 15 * 60 * 1000;
 const DEFAULT_PAGE_LIMIT = 50;
@@ -214,11 +215,7 @@ export class MessagingController {
   ) {
     const from = seqFrom ? Number(seqFrom) : 1;
     const to = seqTo ? Number(seqTo) : Number.MAX_SAFE_INTEGER;
-    const requestedLimit = limit ? Number(limit) : DEFAULT_PAGE_LIMIT;
-    const safeLimit =
-      Number.isFinite(requestedLimit) && requestedLimit > 0
-        ? Math.min(requestedLimit, MAX_PAGE_LIMIT)
-        : DEFAULT_PAGE_LIMIT;
+    const safeLimit = clampLimit(limit, DEFAULT_PAGE_LIMIT, MAX_PAGE_LIMIT);
 
     if (from > to) {
       return {
@@ -251,15 +248,10 @@ export class MessagingController {
     const rows = await qb.limit(safeLimit).getMany();
     const items = rows.map((m) => this.toView(m));
 
-    let nextExpectedSeq = from;
-    for (const row of rows) {
-      if (row.seq > nextExpectedSeq) {
-        break;
-      }
-      if (row.seq === nextExpectedSeq) {
-        nextExpectedSeq += 1;
-      }
-    }
+    const nextExpectedSeq = computeNextExpectedSeq(
+      from,
+      rows.map((row) => row.seq),
+    );
 
     return {
       items,

Fabric.Backend.Guild/src/messaging/pagination.util.spec.ts

@@ -0,0 +1,15 @@
+import { describe, expect, it } from 'vitest';
+import { clampLimit, computeNextExpectedSeq } from './pagination.util';
+
+describe('pagination utils', () => {
+  it('clamps limit safely', () => {
+    expect(clampLimit(undefined, 50, 200)).toBe(50);
+    expect(clampLimit('500', 50, 200)).toBe(200);
+    expect(clampLimit('-1', 50, 200)).toBe(50);
+  });
+
+  it('computes next expected seq', () => {
+    expect(computeNextExpectedSeq(1, [1, 2, 3])).toBe(4);
+    expect(computeNextExpectedSeq(1, [1, 3, 4])).toBe(2);
+  });
+});

Fabric.Backend.Guild/src/messaging/pagination.util.ts

@@ -0,0 +1,14 @@
+export function clampLimit(input: string | undefined, defaultLimit: number, maxLimit: number): number {
+  const requested = input ? Number(input) : defaultLimit;
+  if (!Number.isFinite(requested) || requested <= 0) return defaultLimit;
+  return Math.min(requested, maxLimit);
+}
+
+export function computeNextExpectedSeq(from: number, seqs: number[]): number {
+  let next = from;
+  for (const seq of seqs) {
+    if (seq > next) break;
+    if (seq === next) next += 1;
+  }
+  return next;
+}