From 708550fb7d7440b8baec94fa001ff8a77678eba7 Mon Sep 17 00:00:00 2001
From: MAEDA Go <maeda@farend.jp>
Date: Thu, 2 May 2019 15:24:34 +0900
Subject: [PATCH 2/2] Attachment preview does not support source code in some
 languages

---
 app/models/attachment.rb                        |  2 +-
 lib/redmine/syntax_highlighting.rb              | 12 ++++++++++++
 test/fixtures/files/hello.js                    |  1 +
 test/unit/attachment_test.rb                    | 17 +++++++++++++++++
 .../redmine/syntax_highlighting/rouge_test.rb   | 12 ++++++++++++
 5 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 test/fixtures/files/hello.js

diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index 45560d0dc..362ac1fde 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -237,7 +237,7 @@ class Attachment < ActiveRecord::Base
   end
 
   def is_text?
-    Redmine::MimeType.is_type?('text', filename)
+    Redmine::MimeType.is_type?('text', filename) || Redmine::SyntaxHighlighting.filename_supported?(filename)
   end
 
   def is_image?
diff --git a/lib/redmine/syntax_highlighting.rb b/lib/redmine/syntax_highlighting.rb
index 6e9aa02a7..01fc0d579 100644
--- a/lib/redmine/syntax_highlighting.rb
+++ b/lib/redmine/syntax_highlighting.rb
@@ -52,6 +52,14 @@ module Redmine
       rescue
         false
       end
+
+      def filename_supported?(filename)
+        if highlighter.respond_to? :filename_supported?
+          highlighter.filename_supported? filename
+        else
+          false
+        end
+      end
     end
 
     module Rouge
@@ -101,6 +109,10 @@ module Redmine
         def language_supported?(language)
           find_lexer(language.to_s.downcase) ? true : false
         end
+
+        def filename_supported?(filename)
+          !::Rouge::Lexer.guesses(:filename => filename).empty?
+        end
         
         private
         # Alias names used by CodeRay and not supported by Rouge
diff --git a/test/fixtures/files/hello.js b/test/fixtures/files/hello.js
new file mode 100644
index 000000000..c0380dc44
--- /dev/null
+++ b/test/fixtures/files/hello.js
@@ -0,0 +1 @@
+document.write('Hello, World!');
diff --git a/test/unit/attachment_test.rb b/test/unit/attachment_test.rb
index 1ed1a719e..3a488bb60 100644
--- a/test/unit/attachment_test.rb
+++ b/test/unit/attachment_test.rb
@@ -502,4 +502,21 @@ class AttachmentTest < ActiveSupport::TestCase
     puts '(ImageMagick convert not available)'
   end
 
+  def test_is_text
+    js_attachment = Attachment.new(
+      :container => Issue.find(1), 
+      :file => uploaded_test_file('hello.js', 'application/javascript'),
+      :author => User.find(1))
+
+    to_test = {
+      js_attachment => true,               # hello.js (application/javascript)
+      attachments(:attachments_003) => false, # logo.gif (image/gif)
+      attachments(:attachments_004) => true,  # source.rb (application/x-ruby)
+      attachments(:attachments_015) => true,  # private.diff (text/x-diff)
+      attachments(:attachments_016) => false, # testfile.png (image/png)
+    }
+    to_test.each do |attachment, expected|
+      assert_equal expected, attachment.is_text?
+    end
+  end
 end
diff --git a/test/unit/lib/redmine/syntax_highlighting/rouge_test.rb b/test/unit/lib/redmine/syntax_highlighting/rouge_test.rb
index 0bee260e1..dc0ffcd35 100644
--- a/test/unit/lib/redmine/syntax_highlighting/rouge_test.rb
+++ b/test/unit/lib/redmine/syntax_highlighting/rouge_test.rb
@@ -20,6 +20,18 @@
 require File.expand_path('../../../../../test_helper', __FILE__)
 
 class Redmine::SyntaxHighlighting::RougeTest < ActiveSupport::TestCase
+  def test_filename_supported
+    to_test = {
+      'application.js' => true,
+      'Gemfile' => true,
+      'AUTOEXEC.BAT' => false,
+      'HELLO.C' => true
+    }
+    to_test.each do |filename, expected|
+      assert_equal expected, Redmine::SyntaxHighlighting::Rouge.filename_supported?(filename)
+    end
+  end
+
   def test_highlight_by_filename_should_distinguish_perl_and_prolog
     raw_perl = <<'RAW_PERL'
 #!/usr/bin/perl
-- 
2.20.1 (Apple Git-117)