docs: Remove use of $IP from mwdocgen.php

* Prefer the MW_INSTALL_PATH constant where possible.

* For input and output, there is no need to specify full paths,
  only to strip the prefix again afterwards.
  See also Doxyfile in any repo that is not mediawiki/core where we
  already set the path relative to the project directory, e.g.
  "src/" as input and "docs" as output.

  <https://codesearch.wmcloud.org/search/?q=INPUT%7COUTPUT&files=Doxyfile>

Test Plan:
* `php maintenance/mwdocgen.php --file docs,includes/libs/objectcache/`

Change-Id: I4119161accdc665d0e4d0d4e49d0c42c68f8e2a2

1 files changed, 8 insertions, 11 deletions

diff --git a/maintenance/mwdocgen.php b/maintenance/mwdocgen.php
index cda3d8690715..55ab2b9e9642 100644
--- a/maintenance/mwdocgen.php
+++ b/maintenance/mwdocgen.php
@@ -74,7 +74,7 @@ class MWDocGen extends Maintenance {
 			false, true );
 		$this->addOption( 'file',
 			"Only process given file or directory. Multiple values " .
-			"accepted with comma separation. Path relative to \$IP.",
+			"accepted with comma separation. Path relative to MW_INSTALL_PATH.",
 			false, true );
 		$this->addOption( 'output',
 			'Path to write doc to',
@@ -90,7 +90,7 @@ class MWDocGen extends Maintenance {
 	}
 
 	protected function init() {
-		global $wgPhpCli, $IP;
+		global $wgPhpCli;
 
 		$this->doxygen = $this->getOption( 'doxygen', 'doxygen' );
 		$this->mwVersion = $this->getOption( 'version', 'master' );
@@ -99,26 +99,26 @@ class MWDocGen extends Maintenance {
 		$inputs = explode( ',', $this->getOption( 'file', '' ) );
 		foreach ( $inputs as $input ) {
 			# Doxygen inputs are space separated and double quoted
-			$this->input .= " \"$IP/$input\"";
+			$this->input .= " \"$input\"";
 		}
 
-		$this->output = $this->getOption( 'output', "$IP/docs" );
+		$this->output = $this->getOption( 'output', 'docs' );
 
 		// Do not use wfShellWikiCmd, because mwdoc-filter.php is not
 		// a Maintenance script.
 		$this->inputFilter = Shell::escape( [
 			$wgPhpCli,
-			$IP . '/maintenance/mwdoc-filter.php'
+			MW_INSTALL_PATH . '/maintenance/mwdoc-filter.php'
 		] );
 
-		$this->template = $IP . '/maintenance/Doxyfile';
+		$this->template = MW_INSTALL_PATH . '/maintenance/Doxyfile';
 		$this->excludes = [
 			'cache',
 			'images',
 		];
 		if ( $this->input === '' ) {
 			// If no explicit --file filter is set, we're indexing all of MediaWiki core
-			// in $IP, but not extension and skin submodules (T317451).
+			// in MW_INSTALL_PATH, but not extension and skin submodules (T317451).
 			if ( !$this->hasOption( 'extensions' ) ) {
 				$this->excludes[] = 'extensions';
 			}
@@ -131,20 +131,17 @@ class MWDocGen extends Maintenance {
 	}
 
 	public function execute() {
-		global $IP;
-
 		$this->init();
 
 		# Build out directories we want to exclude
 		$exclude = '';
 		foreach ( $this->excludes as $item ) {
-			$exclude .= " $IP/$item";
+			$exclude .= " $item";
 		}
 
 		$conf = strtr( file_get_contents( $this->template ),
 			[
 				'{{OUTPUT_DIRECTORY}}' => $this->output,
-				'{{STRIP_FROM_PATH}}' => $IP,
 				'{{CURRENT_VERSION}}' => $this->mwVersion,
 				'{{INPUT}}' => $this->input,
 				'{{EXCLUDE}}' => $exclude,