Merge branch 'fix-diff-highlighting' into 'master'

Fix diff syntax highlighting

### What does this MR do?

This MR fixes a syntax highlighting issue that that manifested itself when a user tried the following:

```
+aaa
+bbb
 ccc
```

However, a regression in 0abe98f0 caused the last line to be put on the second to last line:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/a16515499d5e3fd9737370d89c73f671/image.png)

Instead of this:

![image](https://gitlab.com/gitlab-org/gitlab-ce/uploads/59eca6efd4c290aa633b9fb54c98a70e/image.png)

This bug occurred because of some error in the logic of handling new lines in the content. Refactored HTML parser to avoid duplication of newline parsing.

### What are the relevant issue numbers?

Closes #2235

See merge request !1126

1 files changed, 21 insertions, 20 deletions

diff --git a/lib/rouge/formatters/html_gitlab.rb b/lib/rouge/formatters/html_gitlab.rb
index 3f92212243d..6762ca47c32 100644
--- a/lib/rouge/formatters/html_gitlab.rb
+++ b/lib/rouge/formatters/html_gitlab.rb
@@ -93,16 +93,27 @@ module Rouge
       end
 
       def process_tokens(tokens)
-        num_lines = 0
-        last_val = ''
-        rendered = ''
+        rendered = []
+        current_line = ''
 
         tokens.each do |tok, val|
-          last_val = val
-          num_lines += val.scan(/\n/).size
-          rendered << span(tok, val)
+          # In the case of multi-line values (e.g. comments), we need to apply
+          # styling to each line since span elements are inline.
+          val.lines.each do |line|
+            stripped = line.chomp
+            current_line << span(tok, stripped)
+
+            if line.end_with?("\n")
+              rendered << current_line
+              current_line = ''
+            end
+          end
         end
 
+        # Add leftover text
+        rendered << current_line if current_line.present?
+
+        num_lines = rendered.size
         numbers = (@linenostart..num_lines + @linenostart - 1).to_a
 
         { numbers: numbers, code: rendered }
@@ -117,9 +128,8 @@ module Rouge
         numbers.join("\n")
       end
 
-      def wrap_lines(rendered)
+      def wrap_lines(lines)
         if @lineanchors
-          lines = rendered.split("\n")
           lines = lines.each_with_index.map do |line, index|
             number = index + @linenostart
 
@@ -136,24 +146,17 @@ module Rouge
           lines.join("\n")
         else
           if @linenos == 'inline'
-            lines = rendered.split("\n")
             lines = lines.each_with_index.map do |line, index|
               number = index + @linenostart
               "<span class=\"linenos\">#{number}</span>#{line}"
             end
             lines.join("\n")
           else
-            rendered
+            lines.join("\n")
           end
         end
       end
 
-      def wrap_values(val, element)
-        lines = val.split("\n")
-        lines = lines.map{ |x| "<span #{element}>#{x}</span>" }
-        lines.join("\n")
-      end
-
       def span(tok, val)
         # http://stackoverflow.com/a/1600584/2587286
         val = CGI.escapeHTML(val)
@@ -161,13 +164,11 @@ module Rouge
         if tok.shortname.empty?
           val
         else
-          # In the case of multi-line values (e.g. comments), we need to apply
-          # styling to each line since span elements are inline.
           if @inline_theme
             rules = @inline_theme.style_for(tok).rendered_rules
-            wrap_values(val, "style=\"#{rules.to_a.join(';')}\"")
+            "<span style=\"#{rules.to_a.join(';')}\"#{val}</span>"
           else
-            wrap_values(val, "class=\"#{tok.shortname}\"")
+            "<span class=\"#{tok.shortname}\">#{val}</span>"
           end
         end
       end