From 225719993a7b355dbfde5f0a49e6f161d6f75e41 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Bartosz=20Dziewo=C5=84ski?= <matma.rex@gmail.com>
Date: Tue, 25 Aug 2015 09:43:38 +0200
Subject: [PATCH] mediawiki.Uri: Use extended RegExps through templates

JavaScript does not support the 'x' RegExp option for 'extended'
RegExps, or named capturing groups, which makes it impossible to write
large RegExps in a readable way. OR DOES IT?!?

Cons:
* Small runtime performance loss to convert to regular RegExp
* Worse minification due to unminifiable whitespace
    (Both of these problems could probably me resolved
     if we moved the processing server-side somehow,
     but there's no support for it in ResourceLoader now)

Pros:
* You can actually somewhat understand the bloody things if you care
  to, unlike before.

YMMV:
* The actual regexps are in different files

Change-Id: I41630bf20cdb5c2936d85d9f831f2aa7bb8cfef1
---
 resources/Resources.php                       |  8 +++++++
 resources/src/mediawiki/mediawiki.Uri.js      |  8 +++++--
 .../src/mediawiki/mediawiki.Uri.loose.regexp  | 22 +++++++++++++++++++
 .../src/mediawiki/mediawiki.Uri.strict.regexp | 13 +++++++++++
 .../mediawiki/mediawiki.template.regexp.js    | 15 +++++++++++++
 5 files changed, 64 insertions(+), 2 deletions(-)
 create mode 100644 resources/src/mediawiki/mediawiki.Uri.loose.regexp
 create mode 100644 resources/src/mediawiki/mediawiki.Uri.strict.regexp
 create mode 100644 resources/src/mediawiki/mediawiki.template.regexp.js

diff --git a/resources/Resources.php b/resources/Resources.php
index 2293984377..cac87b9203 100644
--- a/resources/Resources.php
+++ b/resources/Resources.php
@@ -849,6 +849,10 @@ return array(
 		),
 		'targets' => array( 'desktop', 'mobile' ),
 	),
+	'mediawiki.template.regexp' => array(
+		'scripts' => 'resources/src/mediawiki/mediawiki.template.regexp.js',
+		'targets' => array( 'desktop', 'mobile' ),
+	),
 	'mediawiki.apipretty' => array(
 		'styles' => 'resources/src/mediawiki/mediawiki.apipretty.css',
 		'targets' => array( 'desktop', 'mobile' ),
@@ -1155,6 +1159,10 @@ return array(
 	),
 	'mediawiki.Uri' => array(
 		'scripts' => 'resources/src/mediawiki/mediawiki.Uri.js',
+		'templates' => array(
+			'strict.regexp' => 'resources/src/mediawiki/mediawiki.Uri.strict.regexp',
+			'loose.regexp' => 'resources/src/mediawiki/mediawiki.Uri.loose.regexp',
+		),
 		'dependencies' => 'mediawiki.util',
 		'targets' => array( 'desktop', 'mobile' ),
 	),
diff --git a/resources/src/mediawiki/mediawiki.Uri.js b/resources/src/mediawiki/mediawiki.Uri.js
index 07d89006b2..ac6c583dc6 100644
--- a/resources/src/mediawiki/mediawiki.Uri.js
+++ b/resources/src/mediawiki/mediawiki.Uri.js
@@ -74,13 +74,17 @@
 	/**
 	 * Regular expressions to parse many common URIs.
 	 *
+	 * As they are gnarly, they have been moved to separate files to allow us to format them in the
+	 * 'extended' regular expression format (which JavaScript normally doesn't support). The subset of
+	 * features handled is minimal, but just the free whitespace gives us a lot.
+	 *
 	 * @private
 	 * @static
 	 * @property {Object} parser
 	 */
 	var parser = {
-		strict: /^(?:([^:\/?#]+):)?(?:\/\/(?:(?:([^:@\/?#]*)(?::([^:@\/?#]*))?)?@)?([^:\/?#]*)(?::(\d*))?)?((?:[^?#\/]*\/)*[^?#]*)(?:\?([^#]*))?(?:#(.*))?/,
-		loose:  /^(?:(?![^:@]+:[^:@\/]*@)([^:\/?#.]+):)?(?:\/\/)?(?:(?:([^:@\/?#]*)(?::([^:@\/?#]*))?)?@)?([^:\/?#]*)(?::(\d*))?((?:\/(?:[^?#](?![^?#\/]*\.[^?#\/.]+(?:[?#]|$)))*\/?)?[^?#\/]*)(?:\?([^#]*))?(?:#(.*))?/
+		strict: mw.template.get( 'mediawiki.Uri', 'strict.regexp' ).render(),
+		loose: mw.template.get( 'mediawiki.Uri', 'loose.regexp' ).render()
 	},
 
 	/**
diff --git a/resources/src/mediawiki/mediawiki.Uri.loose.regexp b/resources/src/mediawiki/mediawiki.Uri.loose.regexp
new file mode 100644
index 0000000000..300ab3bacf
--- /dev/null
+++ b/resources/src/mediawiki/mediawiki.Uri.loose.regexp
@@ -0,0 +1,22 @@
+^
+(?:
+	(?![^:@]+:[^:@/]*@)
+	(?<protocol>[^:/?#.]+):
+)?
+(?://)?
+(?:(?:
+	(?<user>[^:@/?#]*)
+	(?::(?<password>[^:@/?#]*))?
+)?@)?
+(?<host>[^:/?#]*)
+(?::(?<port>\d*))?
+(
+	(?:/
+		(?:[^?#]
+			(?![^?#/]*\.[^?#/.]+(?:[?#]|$))
+		)*/?
+	)?
+	[^?#/]*
+)
+(?:\?(?<query>[^#]*))?
+(?:\#(?<fragment>.*))?
diff --git a/resources/src/mediawiki/mediawiki.Uri.strict.regexp b/resources/src/mediawiki/mediawiki.Uri.strict.regexp
new file mode 100644
index 0000000000..2ac7d2fce9
--- /dev/null
+++ b/resources/src/mediawiki/mediawiki.Uri.strict.regexp
@@ -0,0 +1,13 @@
+^
+(?:(?<protocol>[^:/?#]+):)?
+(?://(?:
+	(?:
+		(?<user>[^:@/?#]*)
+		(?::(?<password>[^:@/?#]*))?
+	)?@)?
+	(?<host>[^:/?#]*)
+	(?::(?<port>\d*))?
+)?
+(?<path>(?:[^?#/]*/)*[^?#]*)
+(?:\?(?<query>[^#]*))?
+(?:\#(?<fragment>.*))?
diff --git a/resources/src/mediawiki/mediawiki.template.regexp.js b/resources/src/mediawiki/mediawiki.template.regexp.js
new file mode 100644
index 0000000000..3ec0a1f5c9
--- /dev/null
+++ b/resources/src/mediawiki/mediawiki.template.regexp.js
@@ -0,0 +1,15 @@
+mediaWiki.template.registerCompiler( 'regexp', {
+	compile: function ( src ) {
+		return {
+			render: function () {
+				return new RegExp(
+					src
+						// Remove whitespace
+						.replace( /\s+/g, '' )
+						// Remove named capturing groups
+						.replace( /\?<\w+?>/g, '' )
+				);
+			}
+		};
+	}
+} );
-- 
2.20.1