Refactor Gitlab::Highlight and fix tests

app/helpers/blob_helper.rb

 module BlobHelper
-  def highlight(blob_name, blob_content, nowrap: false, continue: false)
-    Gitlab::Highlight.highlight(blob_name, blob_content, nowrap: nowrap, continue: continue)
+  def highlighter(blob_name, blob_content, nowrap: false)
+    Gitlab::Highlight.new(blob_name, blob_content, nowrap: nowrap)
+  end
+
+  def highlight(blob_name, blob_content, nowrap: false)
+    Gitlab::Highlight.highlight(blob_name, blob_content, nowrap: nowrap)
   end
 
   def no_highlight_files

app/views/projects/blame/show.html.haml

@@ -15,6 +15,7 @@
     .file-content.blame.highlight
       %table
         - current_line = 1
+        - blame_highlighter = highlighter(@blob.name, @blob.data, nowrap: true)
         - @blame.each do |blame_group|
           %tr
             %td.blame-commit
@@ -41,5 +42,5 @@
               %pre{class: 'code highlight white'}
                 %code
                   - blame_group[:lines].each do |line|
-                    :erb
-                      <%= highlight(@blob.name, line, nowrap: true, continue: true).html_safe %>
+                    :preserve
+                      #{blame_highlighter.highlight(line)}

app/views/shared/_file_highlight.html.haml

@@ -9,5 +9,4 @@
           %i.fa.fa-link
           = i
   .blob-content{data: {blob_id: blob.id}}
-    :preserve
-      #{highlight(blob.name, blob.data)}
+    = highlight(blob.name, blob.data)

lib/gitlab/highlight.rb

 module Gitlab
   class Highlight
-    def self.highlight(blob_name, blob_content, nowrap: true, continue: false)
-      formatter = rouge_formatter(nowrap: nowrap)
-
-      lexer = Rouge::Lexer.guess(filename: blob_name, source: blob_content).new rescue Rouge::Lexers::PlainText
-      formatter.format(lexer.lex(blob_content, continue: continue)).html_safe
+    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)
@@ -14,9 +11,26 @@ module Gitlab
       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(lex(text, continue: continue)).html_safe
+    end
+
     private
 
-    def self.rouge_formatter(options = {})
+    def lex(text, continue: true)
+      if @lexer == Rouge::Lexers::PlainText
+        @lexer.lex(text)
+      else
+        @lexer.lex(text, continue: continue)
+      end
+    end
+
+    def rouge_formatter(options = {})
       options = options.reverse_merge(
         nowrap: true,
         cssclass: 'code highlight',

spec/helpers/blob_helper_spec.rb

 require 'spec_helper'
 
 describe BlobHelper do
-  describe 'highlight' do
-    let(:blob_name) { 'test.lisp' }
-    let(:no_context_content) { ":type \"assem\"))" }
-    let(:blob_content) { "(make-pathname :defaults name\n#{no_context_content}" }
-    let(:split_content) { blob_content.split("\n") }
-    let(:multiline_content) do
-      %q(
-      def test(input):
-        """This is line 1 of a multi-line comment.
-        This is line 2.
-        """
-      )
-    end
+  let(:blob_name) { 'test.lisp' }
+  let(:no_context_content) { ":type \"assem\"))" }
+  let(:blob_content) { "(make-pathname :defaults name\n#{no_context_content}" }
+  let(:split_content) { blob_content.split("\n") }
+  let(:multiline_content) do
+    %q(
+    def test(input):
+      """This is line 1 of a multi-line comment.
+      This is line 2.
+      """
+    )
+  end
 
+  describe '#highlight' do
     it 'should return plaintext for unknown lexer context' do
-      result = highlight(blob_name, no_context_content, nowrap: true, continue: false)
+      result = helper.highlight(blob_name, no_context_content, nowrap: true)
       expect(result).to eq('<span id="LC1" class="line">:type &quot;assem&quot;))</span>')
     end
 
@@ -24,28 +24,17 @@ describe BlobHelper do
       expected = %Q[<span id="LC1" class="line"><span class="p">(</span><span class="nb">make-pathname</span> <span class="ss">:defaults</span> <span class="nv">name</span></span>
 <span id="LC2" class="line"><span class="ss">:type</span> <span class="s">&quot;assem&quot;</span><span class="p">))</span></span>]
 
-      expect(highlight(blob_name, blob_content, nowrap: true, continue: false)).to eq(expected)
-    end
-
-    it 'should highlight continued blocks' do
-      # Both lines have LC1 as ID since formatter doesn't support continue at the moment
-      expected = [
-        '<span id="LC1" class="line"><span class="p">(</span><span class="nb">make-pathname</span> <span class="ss">:defaults</span> <span class="nv">name</span></span>',
-        '<span id="LC1" class="line"><span class="ss">:type</span> <span class="s">&quot;assem&quot;</span><span class="p">))</span></span>'
-      ]
-
-      result = split_content.map{ |content| highlight(blob_name, content, nowrap: true, continue: true) }
-      expect(result).to eq(expected)
+      expect(helper.highlight(blob_name, blob_content, nowrap: true)).to eq(expected)
     end
 
     it 'should highlight multi-line comments' do
-      result = highlight(blob_name, multiline_content, nowrap: true, continue: false)
+      result = helper.highlight(blob_name, multiline_content, nowrap: true)
       html = Nokogiri::HTML(result)
       lines = html.search('.s')
       expect(lines.count).to eq(3)
       expect(lines[0].text).to eq('"""This is line 1 of a multi-line comment.')
-      expect(lines[1].text).to eq('        This is line 2.')
-      expect(lines[2].text).to eq('        """')
+      expect(lines[1].text).to eq('      This is line 2.')
+      expect(lines[2].text).to eq('      """')
     end
 
     context 'diff highlighting' do
@@ -59,9 +48,23 @@ describe BlobHelper do
       end
 
       it 'should highlight each line properly' do
-        result = highlight(blob_name, blob_content, nowrap: true, continue: false)
+        result = helper.highlight(blob_name, blob_content, nowrap: true)
         expect(result).to eq(expected)
       end
     end
   end
+
+  describe "#highlighter" do
+    it 'should highlight continued blocks' do
+      # Both lines have LC1 as ID since formatter doesn't support continue at the moment
+      expected = [
+        '<span id="LC1" class="line"><span class="p">(</span><span class="nb">make-pathname</span> <span class="ss">:defaults</span> <span class="nv">name</span></span>',
+        '<span id="LC1" class="line"><span class="ss">:type</span> <span class="s">&quot;assem&quot;</span><span class="p">))</span></span>'
+      ]
+
+      highlighter = helper.highlighter(blob_name, blob_content, nowrap: true)
+      result = split_content.map{ |content| highlighter.highlight(content) }
+      expect(result).to eq(expected)
+    end
+  end
 end

spec/lib/gitlab/diff/highlight_spec.rb

@@ -8,59 +8,34 @@ describe Gitlab::Diff::Highlight, lib: true do
   let(:diff) { commit.diffs.first }
   let(:diff_file) { Gitlab::Diff::File.new(diff, [commit.parent, commit]) }
 
-  describe '.process_diff_lines' do
-    context 'when processing Gitlab::Diff::Line objects' do
-      let(:diff_lines) { Gitlab::Diff::Highlight.process_diff_lines(diff_file) }
+  describe '#highlight' do
+    let(:diff_lines) { Gitlab::Diff::Highlight.new(diff_file).highlight }
 
-      it 'should return Gitlab::Diff::Line elements' do
-        expect(diff_lines.first).to be_an_instance_of(Gitlab::Diff::Line)
-      end
-
-      it 'should highlight the code' do
-        code = %Q{ <span id="LC7" class="line">  <span class="k">def</span> <span class="nf">popen</span><span class="p">(</span><span class="n">cmd</span><span class="p">,</span> <span class="n">path</span><span class="o">=</span><span class="kp">nil</span><span class="p">)</span></span>\n}
-
-        expect(diff_lines[2].text).to eq(code)
-      end
-
-      it 'should not generate the inline diff markup' do
-        expect(diff_lines[5].text).not_to match(Regexp.new(Regexp.escape('<span class="idiff">')))
-      end
-
-      it 'should not modify "match" lines' do
-        expect(diff_lines[0].text).to eq('@@ -6,12 +6,18 @@ module Popen')
-        expect(diff_lines[22].text).to eq('@@ -19,6 +25,7 @@ module Popen')
-      end
-
-      it 'should highlight unchanged lines' do
-        code = %Q{ <span id="LC7" class="line">  <span class="k">def</span> <span class="nf">popen</span><span class="p">(</span><span class="n">cmd</span><span class="p">,</span> <span class="n">path</span><span class="o">=</span><span class="kp">nil</span><span class="p">)</span></span>\n}
+    it 'should return Gitlab::Diff::Line elements' do
+      expect(diff_lines.first).to be_an_instance_of(Gitlab::Diff::Line)
+    end
 
-        expect(diff_lines[2].text).to eq(code)
-      end
+    it 'should not modify "match" lines' do
+      expect(diff_lines[0].text).to eq('@@ -6,12 +6,18 @@ module Popen')
+      expect(diff_lines[22].text).to eq('@@ -19,6 +25,7 @@ module Popen')
+    end
 
-      it 'should highlight added lines' do
-        code = %Q{+<span id="LC9" class="line">      <span class="k">raise</span> <span class="no">RuntimeError</span><span class="p">,</span> <span class="s2">&quot;System commands must be given as an array of strings&quot;</span></span>\n}
+    it 'should highlight unchanged lines' do
+      code = %Q{ <span id="LC7" class="line">  <span class="k">def</span> <span class="nf">popen</span><span class="p">(</span><span class="n">cmd</span><span class="p">,</span> <span class="n">path</span><span class="o">=</span><span class="kp">nil</span><span class="p">)</span></span>\n}
 
-        expect(diff_lines[5].text).to eq(code)
-      end
+      expect(diff_lines[2].text).to eq(code)
+    end
 
-      it 'should highlight removed lines' do
-        code = %Q{-<span id="LC9" class="line">      <span class="k">raise</span> <span class="s2">&quot;System commands must be given as an array of strings&quot;</span></span>\n}
+    it 'should highlight removed lines' do
+      code = %Q{-<span id="LC9" class="line">      <span class="k">raise</span> <span class="s2">&quot;System commands must be given as an array of strings&quot;</span></span>\n}
 
-        expect(diff_lines[4].text).to eq(code)
-      end
+      expect(diff_lines[4].text).to eq(code)
     end
-  end
 
-  describe '.highlight_lines' do
-    let(:lines) do
-      Gitlab::Diff::Highlight.highlight_lines(project.repository, commit.id, 'files/ruby/popen.rb')
-    end
+    it 'should highlight added lines' do
+      code = %Q{+<span id="LC9" class="line">      <span class="k">raise</span> <span class="no"><span class='idiff'>RuntimeError</span></span><span class="p"><span class='idiff'>,</span></span> <span class="s2">&quot;System commands must be given as an array of strings&quot;</span></span>\n}
 
-    it 'should properly highlight all the lines' do
-      expect(lines[4]).to eq(%Q{<span id="LC5" class="line">  <span class="kp">extend</span> <span class="nb">self</span></span>\n})
-      expect(lines[21]).to eq(%Q{<span id="LC22" class="line">    <span class="k">unless</span> <span class="no">File</span><span class="p">.</span><span class="nf">directory?</span><span class="p">(</span><span class="n">path</span><span class="p">)</span></span>\n})
-      expect(lines[26]).to eq(%Q{<span id="LC27" class="line">    <span class="vi">@cmd_status</span> <span class="o">=</span> <span class="mi">0</span></span>\n})
+      expect(diff_lines[5].text).to eq(code)
     end
   end
-
 end