Redmine::SyntaxHighlighting.highlight_by_filename may not be able to determine the language by filename alone (#31285).

Patch by Go MAEDA.


git-svn-id: http://svn.redmine.org/redmine/trunk@18118 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/syntax_highlighting.rb

@@ -85,7 +85,7 @@ module Redmine
           # See also: https://github.com/jneen/rouge/pull/1078
           text = text.gsub(/\r\n?/, "\n")
 
-          lexer =::Rouge::Lexer.guess_by_filename(filename)
+          lexer =::Rouge::Lexer.guess(:source => text, :filename => filename)
           formatter = ::Rouge::Formatters::HTML.new
           ::Rouge.highlight(text, lexer, CustomHTMLLinewise.new(formatter))
         end

test/unit/lib/redmine/syntax_highlighting/rouge_test.rb

@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+# Redmine - project management software
+# Copyright (C) 2006-2017  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+require File.expand_path('../../../../../test_helper', __FILE__)
+
+class Redmine::SyntaxHighlighting::RougeTest < ActiveSupport::TestCase
+  def test_highlight_by_filename_should_distinguish_perl_and_prolog
+    raw_perl = <<'RAW_PERL'
+#!/usr/bin/perl
+print "Hello, world!\n";
+RAW_PERL
+    expected_perl = <<'EXPECTED_PERL'
+<span class="c1">#!/usr/bin/perl</span>
+<span class="k">print</span> <span class="s">"Hello, world!\n"</span><span class="p">;</span>
+EXPECTED_PERL
+    raw_prolog = <<'RAW_PROLOG'
+#!/usr/bin/swipl
+:- writeln('Hello, world!'),halt.
+RAW_PROLOG
+    expected_prolog = <<'EXPECTED_PROLOG'
+<span class="c1">#!/usr/bin/swipl</span>
+<span class="p">:-</span> <span class="ss">writeln</span><span class="p">(</span><span class="ss">'Hello, world!'</span><span class="p">),</span><span class="ss">halt</span><span class="p">.</span>
+EXPECTED_PROLOG
+
+    filename = 'hello.pl'
+
+    # Rouge cannot distinguish between Perl and Prolog by filename alone
+    assert_raises Rouge::Guesser::Ambiguous do
+      Rouge::Lexer.guess(:filename => filename)
+    end
+    assert_equal Rouge::Lexers::Perl, Rouge::Lexer.guess(:filename => filename, :source => raw_perl)
+    assert_equal Rouge::Lexers::Prolog, Rouge::Lexer.guess(:filename => filename, :source => raw_prolog)
+
+    assert_equal expected_perl, Redmine::SyntaxHighlighting::Rouge.highlight_by_filename(raw_perl, filename)
+    assert_equal expected_prolog, Redmine::SyntaxHighlighting::Rouge.highlight_by_filename(raw_prolog, filename)
+  end
+end