[NFC] CRM_Utils_SystemTest - Call to Uri->withPath() using deprecated format

[demeritcowboy]

Overview

Addresses test fails in #21064.

Before

CRM_Utils_SystemTest::testAlterExternUrlHook with data set 0 ('extern/url', array('extern/url', 'u=1&qid=1'))
Exception: The path of a URI with an authority must start with a slash "/" or be empty. Automagically fixing the URI by adding a leading slash to the path is deprecated since version 1.4 and will throw an exception instead.

CRM_Utils_SystemTest::testAlterExternUrlHook with data set 1 ('extern/open', array('extern/open', 'q=1'))
Exception: The path of a URI with an authority must start with a slash "/" or be empty. Automagically fixing the URI by adding a leading slash to the path is deprecated since version 1.4 and will throw an exception instead.

After

Technical Details

Guzzle uses the same "technique" (I'm trying to use a nice word) as drupal 8 that was the reason we didn't see any of the deprecations, even in logs on dev sites, until people started using drupal 9 and it hard-crashed. You only see these if you're using a special error handler: https://github.com/guzzle/psr7/blob/1.6.1/src/Uri.php#L751

Comments

[civibot]

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[seamuslee001]

This seems fine to me