[wit3]

Guzzle 8.0 is out, and Laravel 13 already accepts it (guzzlehttp/guzzle: ^7.8.2 || ^8.0). Forrest's ~6.0|~7.0 is now the constraint that keeps applications on Guzzle 7. Widening it isn't enough on its own, though: against Guzzle 8.2.0, unpatched master breaks in three places.

1. Client::assignExceptions() fatals on every error response. Guzzle 8 moved the response from RequestException to the new ResponseException subclass, and RequestException no longer has hasResponse()/getResponse(). Every 4xx/5xx fails with "Call to undefined method", including the 401 that should trigger the token refresh.
2. SalesforceException / TokenExpiredException can't be built. They pass $e->getResponse() as the third argument of RequestException::__construct(), which in Guzzle 8 is int $code (TypeError). ResponseException's constructor is final, so extending it isn't an option.
3. HTTP methods are sent lowercase. Guzzle 8 preserves the method casing it is given. Forrest passes 'get'/'post' (and the user-supplied 'method' => 'patch'), so they would reach Salesforce verbatim.

Changes

• composer.json: guzzlehttp/guzzle: ~6.0|~7.0|^8.0.
• Methods are uppercased in handleRequest(), and the literal 'get'/'post' in Client and the authentication classes are now 'GET'/'POST'. Nothing changes on Guzzle 6/7, which already uppercased them on the wire.
• New Exceptions\WrapsRequestException trait, used by SalesforceException and TokenExpiredException:
  • Both classes still extend RequestException and keep their ($message, RequestException $e) constructor.
  • They store the response themselves and expose the same getResponse(): ?ResponseInterface and hasResponse(): bool, so catch blocks that call $e->getResponse() keep working on both majors.
  • The parent constructor call is chosen by class_exists(ResponseException::class).
  • The exception code is still the HTTP status.
• assignExceptions() reads the response through WrapsRequestException::responseFrom(), which handles both shapes.

Tests

• TestCase::requestException() uses RequestException::create(), which exists on both majors.
• Unit tests that expected lowercase methods now expect uppercase.
• Three new tests in ClientTest drive a real GuzzleHttp\Client (MockHandler + history middleware) instead of a mocked ClientInterface. The mocked tests never reach Guzzle's request pipeline, which is why 45/46 of them still passed on Guzzle 8 while the library was broken. The new tests cover:
  • 401 → refresh → retry, with GET on both requests;
  • a 400 wrapped in SalesforceException with getResponse(), hasResponse(), getCode(), the message and getPrevious();
  • 'method' => 'patch' sent as PATCH.

Local runs on PHP 8.5:

	master	this PR
Guzzle 7.15.5	✅	✅ 49 tests
Guzzle 8.2.0	❌ 8 failing (with these tests)	✅ 49 tests

No workflow change is needed: the existing matrix already resolves Guzzle 7 on Laravel 11/12 (^7.8.2) and Guzzle 8 on Laravel 13.

Not covered here: UserPasswordSoap has no test that goes through a real client. Its only change is 'post' → 'POST'.