fix(testing): add retry logic for testing token fetch on 429/5xx

[jacekradko]

Summary

• Add retry with exponential backoff to the testing token fetch in @clerk/testing
• The fetchEnvVars function calls testingTokens.createTestingToken() without retry handling, causing E2E test failures when FAPI returns 429 (Too Many Requests)
• Retries up to 5 times on 429, 502, 503, 504 with exponential backoff + jitter, matching the existing retryableClerkClient used in integration tests

Test plan

• Verify @clerk/testing builds successfully
• Run E2E tests with concurrent workers to confirm 429s are retried instead of failing immediately

Summary by CodeRabbit

Tests

• Added automatic retry logic for testing token operations when encountering rate limits or transient server errors, with exponential backoff.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 65b0620

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
clerk-js-sandbox	Ready	Preview, Comment	Mar 20, 2026 2:17pm

[pkg-pr-new]

Open in StackBlitz

@clerk/agent-toolkit

npm i https://pkg.pr.new/@clerk/agent-toolkit@8138

@clerk/astro

npm i https://pkg.pr.new/@clerk/astro@8138

@clerk/backend

npm i https://pkg.pr.new/@clerk/backend@8138

@clerk/chrome-extension

npm i https://pkg.pr.new/@clerk/chrome-extension@8138

@clerk/clerk-js

npm i https://pkg.pr.new/@clerk/clerk-js@8138

@clerk/dev-cli

npm i https://pkg.pr.new/@clerk/dev-cli@8138

@clerk/expo

npm i https://pkg.pr.new/@clerk/expo@8138

@clerk/expo-passkeys

npm i https://pkg.pr.new/@clerk/expo-passkeys@8138

@clerk/express

npm i https://pkg.pr.new/@clerk/express@8138

@clerk/fastify

npm i https://pkg.pr.new/@clerk/fastify@8138

@clerk/hono

npm i https://pkg.pr.new/@clerk/hono@8138

@clerk/localizations

npm i https://pkg.pr.new/@clerk/localizations@8138

@clerk/nextjs

npm i https://pkg.pr.new/@clerk/nextjs@8138

@clerk/nuxt

npm i https://pkg.pr.new/@clerk/nuxt@8138

@clerk/react

npm i https://pkg.pr.new/@clerk/react@8138

@clerk/react-router

npm i https://pkg.pr.new/@clerk/react-router@8138

@clerk/shared

npm i https://pkg.pr.new/@clerk/shared@8138

@clerk/tanstack-react-start

npm i https://pkg.pr.new/@clerk/tanstack-react-start@8138

@clerk/testing

npm i https://pkg.pr.new/@clerk/testing@8138

@clerk/ui

npm i https://pkg.pr.new/@clerk/ui@8138

@clerk/upgrade

npm i https://pkg.pr.new/@clerk/upgrade@8138

@clerk/vue

npm i https://pkg.pr.new/@clerk/vue@8138

commit: 65b0620

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository YAML (base), Organization UI (inherited)

Review profile: ASSERTIVE

Plan: Pro

Run ID: cc2010cb-3a86-44f2-a816-efbad2665e35

📥 Commits

Reviewing files that changed from the base of the PR and between e722e7d and 65b0620.

📒 Files selected for processing (1)

• packages/testing/src/common/setup.ts

---

📝 Walkthrough

Walkthrough

The change introduces a new internal helper function fetchWithRetry in the testing setup module that adds retry logic for async operations. This function retries failed calls up to a maximum number of attempts when the error is a Clerk API response error with status codes 429, 502, 503, or 504. Retry delays are calculated from the error's retryAfter property when available, otherwise using exponential backoff with jitter. The retry attempts are logged via console.warn. The testing token fetch operation was updated to use this helper while maintaining existing error handling that logs failures and rethrows errors.

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly and accurately summarizes the main change: adding retry logic for testing token fetch on specific HTTP error codes (429, 5xx). It clearly identifies both what was changed (testing token fetch) and why (retry logic for 429/5xx errors).

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

📝 Coding Plan

• Generate coding plan for human review comments

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}