From 5676481c6d7e06693bc925c18fb652adbd5e36b5 Mon Sep 17 00:00:00 2001
From: "C. Scott Ananian" <cscott@cscott.net>
Date: Fri, 8 Sep 2017 23:44:42 -0400
Subject: [PATCH] Remove "only newlines in trailer" special case for
 category/language links

This special case complicates wikitext semantics and ought to be
unnecessary.  Parsoid doesn't include this special case; if this patch
to the PHP parser isn't merged, we should write one for Parsoid to
implement the missing special case logic.

Bug: T175416
Change-Id: I3865c51b21de9d63ac5d06dcc3a3fa9108129d6c
---
 includes/parser/Parser.php   | 10 ++--------
 tests/parser/parserTests.txt | 10 +++++-----
 2 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/includes/parser/Parser.php b/includes/parser/Parser.php
index 0d11d5a397..fe8622a5ea 100644
--- a/includes/parser/Parser.php
+++ b/includes/parser/Parser.php
@@ -2299,10 +2299,7 @@ class Parser {
 					/**
 					 * Strip the whitespace interwiki links produce, see T10897
 					 */
-					$s = rtrim( $s . $prefix );
-					// Special case: strip newlines when only thing between
-					// this link and next are newlines
-					$s .= trim( $trail, "\n" ) === '' ? '' : $trail;
+					$s = rtrim( $s . $prefix ) . $trail; # T175416
 					continue;
 				}
 
@@ -2330,10 +2327,7 @@ class Parser {
 					/**
 					 * Strip the whitespace Category links produce, see T2087
 					 */
-					$s = rtrim( $s . $prefix ); # T2087, T87753
-					// Special case: strip newlines when only thing between
-					// this link and next are newlines
-					$s .= trim( $trail, "\n" ) === '' ? '' : $trail;
+					$s = rtrim( $s . $prefix ) . $trail; # T2087, T87753
 
 					if ( $wasblank ) {
 						$sortkey = $this->getDefaultSort();
diff --git a/tests/parser/parserTests.txt b/tests/parser/parserTests.txt
index ca16738219..9a08b47a29 100644
--- a/tests/parser/parserTests.txt
+++ b/tests/parser/parserTests.txt
@@ -16140,11 +16140,9 @@ parsoid=wt2html,html2html
 <a rel="mw:WikiLink" href="./Foo" title="Foo">Foo</a></div>
 !! end
 
-# NOTE that Parsoid does not currently implement this special case
-# (T175416).  The plan is to remove this weird special-case in the PHP
-# parser to make it match the Parsoid output.
+# Note that Parsoid differs slightly from PHP due to T175421
 !! test
-11. Special case where only newlines separate links
+11. Special case where only newlines separate links (T175416)
 !! options
 parsoid=wt2html,html2html
 !! wikitext
@@ -16154,7 +16152,9 @@ parsoid=wt2html,html2html
 
 [[Foo]]
 !! html/php
-<p><a href="/wiki/Foo" title="Foo">Foo</a><a href="/wiki/Foo" title="Foo">Foo</a>
+<p><br />
+<a href="/wiki/Foo" title="Foo">Foo</a>
+</p><p><a href="/wiki/Foo" title="Foo">Foo</a>
 </p>
 !! html/parsoid
 <link rel="mw:PageProp/Category" href="./Category:Foo"/>
-- 
2.20.1