1 files changed, 39 insertions, 0 deletions
diff --git a/lib/gitlab/highlight.rb b/lib/gitlab/highlight.rb
new file mode 100644
index 00000000000..cac76442321
--- /dev/null
+++ b/lib/gitlab/highlight.rb
@@ -0,0 +1,39 @@
+module Gitlab
+  class Highlight
+    def self.highlight(blob_name, blob_content, nowrap: true)
+      new(blob_name, blob_content, nowrap: nowrap).highlight(blob_content, continue: false)
+    end
+
+    def self.highlight_lines(repository, ref, file_name)
+      blob = repository.blob_at(ref, file_name)
+      return [] unless blob
+
+      blob.load_all_data!(repository)
+      highlight(file_name, blob.data).lines.map!(&:html_safe)
+    end
+
+    def initialize(blob_name, blob_content, nowrap: true)
+      @formatter = rouge_formatter(nowrap: nowrap)
+      @lexer = Rouge::Lexer.guess(filename: blob_name, source: blob_content).new rescue Rouge::Lexers::PlainText
+    end
+
+    def highlight(text, continue: true)
+      @formatter.format(@lexer.lex(text, continue: continue)).html_safe
+    rescue
+      @formatter.format(Rouge::Lexers::PlainText.lex(text)).html_safe
+    end
+
+    private
+
+    def rouge_formatter(options = {})
+      options = options.reverse_merge(
+        nowrap: true,
+        cssclass: 'code highlight',
+        lineanchors: true,
+        lineanchorsid: 'LC'
+      )
+
+      Rouge::Formatters::HTMLGitlab.new(options)
+    end
+  end
+end