Add passthrough arguments to PHP binary via -- separator

[Copilot]

Implementation Plan: Passthrough Arguments via --

• Explore repository structure and understand current implementation
• Modify Server_Command.php to capture and handle passthrough arguments after --
• Update command documentation with the new passthrough feature
• Add Behat tests to verify passthrough arguments work correctly
• Address review feedback:
  • Update test to actually verify the passthrough arg was applied (outputs memory_limit value)
  • Remove dead code (-- check in loop), simplify with str_repeat + array_merge
  • Add @param annotations for $args and $assoc_args

Original prompt

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This section details on the original issue you should resolve

<issue_title>Passthrough args via --?</issue_title>
<issue_description>## Feature Request

• Yes, I reviewed the contribution guidelines.

Describe your use case and the problem you are facing

I want to load Xdebug module into the web server via php -S -dzend_extension=xdebug.so.

Describe the solution you'd like

wp server could pass through additional arguments to php after -- argument.

Example: wp server --docroot=public -- -dzend_extension=xdebug.so

Doing this via wp server --config argument is problematic, because I want to define universally usable commands centrally in composer.json scripts. Due to variety of INI configuration file locations on user's system, which we actually don't want to replace, this doesn't seem to be achievable with a single --config argument.</issue_description>

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

@schlessera Sounds like a reasonable use case.

• Fixes Passthrough args via --? #59

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/Server_Command.php	0.00%	12 Missing ⚠️
server-command.php	0.00%	1 Missing ⚠️

📢 Thoughts on this report? Let us know!

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

Utils\esc_cmd( $cmd_format, ...$cmd_args ) uses argument unpacking (...), which is only available starting with PHP 5.6. This package explicitly supports PHP 5.4+ (see the server-command.php version check / feature tag), so this will cause a parse error on PHP 5.4/5.5. Use a PHP 5.4-compatible approach to pass a dynamic argument list (e.g., call_user_func_array() with the format string prepended to the args array).

Suggested change

	$cmd = Utils\esc_cmd( $cmd_format, ...$cmd_args );
	$esc_cmd_args = $cmd_args;
	array_unshift( $esc_cmd_args, $cmd_format );
	$cmd = call_user_func_array( 'WP_CLI\Utils\esc_cmd', $esc_cmd_args );

[swissspidy]

@copilot This is incorrect. We require PHP 7.2+. Remove that check from server-command.php

[Copilot]

Done in 820f666. Removed the before_invoke PHP 5.4 version check from server-command.php and updated the @require-php-5.4 Behat feature tag to @require-php-7.2 to match the actual requirement.

[Copilot]

The PHPDoc array-shape for $assoc_args doesn't match the actual values used in this method: port is an int by default, and both docroot and config can be false (see $defaults). With phpstan.neon.dist no longer suppressing missing types, this mismatch can lead to incorrect static analysis results. Update the PHPDoc to reflect the real types (e.g., port: int|string, docroot: string|false, config: string|false).

Suggested change

	* @param array{host: string, port: string, docroot?: string, config?: string} $assoc_args Associative arguments passed to the command.
	* @param array{host: string, port: int|string, docroot?: string|false, config?: string|false} $assoc_args Associative arguments passed to the command.