Fix baseURL double-prefix when request path starts with /

[Copilot]

When using axios.create({ baseURL: '/api' }) with a path starting with /, the baseURL was applied twice — producing /api/api/auth/login instead of /api/auth/login — causing a URL parse failure.

Root Cause

src/instance.ts calls buildUrl() to resolve the full URL, then passes the entire instanceConfig (still containing baseURL) to core/request.ts. Since core/request.ts calls buildUrl() again, relative baseURL values got applied a second time. Absolute baseURLs were unaffected because the resulting URL passes isAbsoluteUrl() and is used as-is.

Fix

Strip baseURL and url from instanceConfig before handing off to core/request.ts, since URL resolution is already complete at that point.

// src/instance.ts — before
return request(instanceConfig.url!, instanceConfig, instanceChain);

// after
const { baseURL: _baseURL, url: _url, ...resolvedInstanceConfig } = instanceConfig;
return request(instanceConfig.url!, resolvedInstanceConfig, instanceChain);

Tests

• test/unit/instance-baseurl.test.ts: stubs global.fetch to assert the exact URL sent — /api/auth/login, not /api/api/auth/login
• test/axios/compatibility.test.ts: adds an integration case for axios.create with a baseURL containing a path segment and a leading-slash request path

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• api.example.com
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js (dns block)
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js b.com/dev-dami/kiattp/sessions/5761a7d0-5bf0-440b-9347-d3a3f6abbc83 k/_temp/ghcca-node/node/bin/git logs s ost:*;127.0.0.1;--noprofile /home/REDACTED/work/_temp/ghcca-node/node/bin/node --en�� /home/REDACTED/work/_temp/copilot-developer-action-main/dist/indexcredential.helper (dns block)
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js --global tnet/tools/git user.name (dns block)
• this-host-does-not-exist-xyz123.test
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js (dns block)
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js --global 1/x64/bin/node user.name (dns block)
  • Triggering command: /opt/hostedtoolcache/node/24.14.1/x64/bin/node /opt/hostedtoolcache/node/24.14.1/x64/bin/node --conditions development --conditions node /home/REDACTED/work/kiattp/kiattp/node_modules/tinypool/dist/entry/process.js aseurl.test.ts node_modules/.bin/sh (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)