Fix router to properly set $_SERVER variables for entry points and pretty permalinks

[Copilot]

Plan: Support pretty permalinks and multiple WordPress entry points

Problem

The current router.php doesn't properly set $_SERVER variables when routing requests to PHP files. This causes issues with:

• wp-login.php and other entry points
• Pretty permalinks
• WordPress's URL detection logic

Root Cause

When the router requires a PHP file (like wp-login.php or index.php), the $_SERVER variables still reflect the router script, not the actual PHP file being executed. WordPress relies on these variables to determine the current URL and script.

Solution Plan

• Fix $_SERVER variable handling in router.php
  • Set SCRIPT_NAME to the correct PHP file being executed
  • Set PHP_SELF to match SCRIPT_NAME
  • Set SCRIPT_FILENAME to the full path of the PHP file
• Improve file type detection (check file extension properly instead of using strpos)
• Add test cases for pretty permalinks and wp-login.php access
• Fix test scenarios to avoid dependencies and timing issues
• Use wp option update instead of wp rewrite structure in tests

Changes Made

1. router.php

Improved PHP file detection:

• Replaced strpos($wpcli_server_path, '.php') with pathinfo($wpcli_server_path, PATHINFO_EXTENSION) === 'php'
• This prevents false positives with directory names containing .php (e.g., /my.php-files/image.jpg)

Fixed $_SERVER variables for PHP entry points:
When routing to any PHP file (wp-login.php, wp-admin/index.php, etc.):

• $_SERVER['SCRIPT_NAME'] = the requested PHP file path (e.g., /wp-login.php)
• $_SERVER['PHP_SELF'] = same as SCRIPT_NAME
• $_SERVER['SCRIPT_FILENAME'] = full filesystem path to the PHP file

Fixed $_SERVER variables for pretty permalinks:
When routing non-existent URLs to index.php:

• $_SERVER['SCRIPT_NAME'] = /index.php
• $_SERVER['PHP_SELF'] = /index.php
• $_SERVER['SCRIPT_FILENAME'] = full path to index.php
• $_SERVER['REQUEST_URI'] = unchanged, preserving the pretty URL

2. features/server.feature

Test scenarios:

• Access wp-login.php: Uses explicit http:// protocol and checks for "wp-login.php" in HTML output
• Pretty permalinks: Uses wp option update permalink_structure to set permalink structure, then tests accessing default post with query parameter

Manual Testing Completed

✅ Direct PHP file access (test-entry.php) - $_SERVER variables correctly set
✅ Pretty permalink routing (/some-pretty-url/) - routed to index.php with correct variables
✅ Static file serving (test.txt) - served correctly by PHP's built-in server
✅ Edge case: directory with .php in name - handled correctly with pathinfo()

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Support pretty permalinks</issue_title>
<issue_description>- [x] Yes, I reviewed the contribution guidelines.

Describe your use case and the problem you are facing

wp server does not handle wp-login.php and, more generally, any WP entry-point other than index.php

Describe the solution you'd like

Hardwiring entrypoints logic (or even parse the htaccess using PHP) in order to support them would make it.

A fully browsable WordPress instance off Apache/nginx/php-fpm would be handy in Q&A situations/simulations. The (probably < 100) lines needed may be worth it.

If login.php is requested by the client, that file would be require'd dynamically.
Some tweaks to $_SERVER may be needed though in order to mimic mod_rewrite behavior. </issue_description>

Comments on the Issue (you are @copilot in this section)

@swissspidy WP-CLI already has such a router script, so not sure what's missing there 🤔

• Fixes Support pretty permalinks #56

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[gemini-code-assist]

Code Review

This pull request fixes the built-in server's router to correctly handle $_SERVER variables, enabling support for pretty permalinks and direct access to PHP entry points like wp-login.php. The changes in router.php are solid, correctly detecting PHP files and setting the necessary server variables to mimic direct file access or route to index.php. The addition of test cases is great. I've suggested an improvement to the pretty permalinks test to make it more robust by testing an actual pretty URL instead of a query parameter-based one.

[gemini-code-assist]

The scenario is named "Pretty permalinks", but the test uses curl ... /?p=1, which is a plain permalink. This doesn't fully validate that pretty permalinks are working as intended with the new router logic for non-existent files.

To make this test more robust and accurately reflect its name, I suggest testing an actual pretty URL like /hello-world/. This will require flushing the rewrite rules after setting the permalink structure. Using curl -L is also recommended to follow any potential redirects.

    And I run `wp option update permalink_structure '/%postname%/'`
    And I run `wp rewrite flush`

    When I run `curl -sSL http://localhost:8183/hello-world/`
    Then STDOUT should contain:
      """
      Hello world!
      """

[swissspidy]

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