Remove user_color_scheme_class

Instead of rendering this value server-side, we use Javascript and Gon
to apply the user's color scheme (or the default) to any syntax
highlighted code blocks.

This will make it easier to cache these blocks in the future because
they're no longer state-dependent.

11 files changed, 21 insertions, 41 deletions

diff --git a/app/assets/javascripts/syntax_highlight.coffee b/app/assets/javascripts/syntax_highlight.coffee
new file mode 100644
index 00000000000..510f15d1b49
--- /dev/null
+++ b/app/assets/javascripts/syntax_highlight.coffee
@@ -0,0 +1,9 @@
+# Applies a syntax highlighting color scheme CSS class to any element with the
+# `js-syntax-highlight` class
+#
+# ### Example Markup
+#
+#   <div class="js-syntax-highlight"></div>
+#
+$(document).on 'ready page:load', ->
+  $('.js-syntax-highlight').addClass(gon.user_color_scheme)
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 12d439b0b31..b51a9600c18 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -190,11 +190,12 @@ class ApplicationController < ActionController::Base
   end
 
   def add_gon_variables
+    gon.api_version            = API::API.version
+    gon.default_avatar_url     = URI::join(Gitlab.config.gitlab.url, ActionController::Base.helpers.image_path('no_avatar.png')).to_s
     gon.default_issues_tracker = Project.new.default_issue_tracker.to_param
-    gon.api_version = API::API.version
-    gon.relative_url_root = Gitlab.config.gitlab.relative_url_root
-    gon.default_avatar_url = URI::join(Gitlab.config.gitlab.url, ActionController::Base.helpers.image_path('no_avatar.png')).to_s
-    gon.max_file_size = current_application_settings.max_attachment_size;
+    gon.max_file_size          = current_application_settings.max_attachment_size
+    gon.relative_url_root      = Gitlab.config.gitlab.relative_url_root
+    gon.user_color_scheme      = Gitlab::ColorSchemes.for_user(current_user).css_class
 
     if current_user
       gon.current_user_id = current_user.id
diff --git a/app/helpers/gitlab_markdown_helper.rb b/app/helpers/gitlab_markdown_helper.rb
index eb3f72a307d..114730eb948 100644
--- a/app/helpers/gitlab_markdown_helper.rb
+++ b/app/helpers/gitlab_markdown_helper.rb
@@ -58,7 +58,7 @@ module GitlabMarkdownHelper
       @options = options
 
       # see https://github.com/vmg/redcarpet#darling-i-packed-you-a-couple-renderers-for-lunch
-      rend = Redcarpet::Render::GitlabHTML.new(self, user_color_scheme_class, options)
+      rend = Redcarpet::Render::GitlabHTML.new(self, options)
 
       # see https://github.com/vmg/redcarpet#and-its-like-really-simple-to-use
       @markdown = Redcarpet::Markdown.new(rend, MARKDOWN_OPTIONS)
diff --git a/app/helpers/preferences_helper.rb b/app/helpers/preferences_helper.rb
index b294ddc9d72..51a6b3fa997 100644
--- a/app/helpers/preferences_helper.rb
+++ b/app/helpers/preferences_helper.rb
@@ -33,10 +33,6 @@ module PreferencesHelper
     Gitlab::Themes.by_id(current_user.try(:theme_id)).css_class
   end
 
-  def user_color_scheme_class
-    Gitlab::ColorSchemes.by_id(current_user.try(:color_scheme_id)).css_class
-  end
-
   def prefer_readme?
     !current_user ||
       current_user.project_view == 'readme'
diff --git a/app/views/search/results/_blob.html.haml b/app/views/search/results/_blob.html.haml
index 58f58eff54d..0fe8a3b490a 100644
--- a/app/views/search/results/_blob.html.haml
+++ b/app/views/search/results/_blob.html.haml
@@ -7,4 +7,4 @@
         %strong
           = blob.filename
     .file-content.code.term
-      = render 'shared/file_highlight', blob: blob, first_line_number: blob.startline, user_color_scheme_class: 'white'
+      = render 'shared/file_highlight', blob: blob, first_line_number: blob.startline
diff --git a/app/views/search/results/_snippet_blob.html.haml b/app/views/search/results/_snippet_blob.html.haml
index 95099853918..19a7bfefef5 100644
--- a/app/views/search/results/_snippet_blob.html.haml
+++ b/app/views/search/results/_snippet_blob.html.haml
@@ -23,7 +23,7 @@
                 .nothing-here-block Empty file
       - else
         .file-content.code
-          %div.highlighted-data{class: user_color_scheme_class}
+          %div.highlighted-data.js-syntax-highlight
             .line-numbers
               - snippet_blob[:snippet_chunks].each do |snippet|
                 - unless snippet[:data].empty?
diff --git a/app/views/search/results/_wiki_blob.html.haml b/app/views/search/results/_wiki_blob.html.haml
index c03438eb952..f5859481d46 100644
--- a/app/views/search/results/_wiki_blob.html.haml
+++ b/app/views/search/results/_wiki_blob.html.haml
@@ -7,4 +7,4 @@
         %strong
           = wiki_blob.filename
     .file-content.code.term
-      = render 'shared/file_highlight', blob: wiki_blob, first_line_number: wiki_blob.startline, user_color_scheme_class: 'white'
+      = render 'shared/file_highlight', blob: wiki_blob, first_line_number: wiki_blob.startline
diff --git a/app/views/shared/_file_highlight.html.haml b/app/views/shared/_file_highlight.html.haml
index d6a2e177da1..7b1c624d769 100644
--- a/app/views/shared/_file_highlight.html.haml
+++ b/app/views/shared/_file_highlight.html.haml
@@ -1,4 +1,4 @@
-.file-content.code{class: user_color_scheme_class}
+.file-content.code.js-syntax-highlight
   .line-numbers
     - if blob.data.present?
       - blob.data.lines.each_index do |index|
diff --git a/lib/redcarpet/render/gitlab_html.rb b/lib/redcarpet/render/gitlab_html.rb
index f57b56cbdf0..9cb8e91d6e3 100644
--- a/lib/redcarpet/render/gitlab_html.rb
+++ b/lib/redcarpet/render/gitlab_html.rb
@@ -4,9 +4,8 @@ class Redcarpet::Render::GitlabHTML < Redcarpet::Render::HTML
   attr_reader :template
   alias_method :h, :template
 
-  def initialize(template, color_scheme, options = {})
+  def initialize(template, options = {})
     @template = template
-    @color_scheme = color_scheme
     @options = options.dup
 
     @options.reverse_merge!(
@@ -35,7 +34,7 @@ class Redcarpet::Render::GitlabHTML < Redcarpet::Render::HTML
     end
 
     formatter = Rouge::Formatters::HTMLGitlab.new(
-      cssclass: "code highlight #{@color_scheme} #{lexer.tag}"
+      cssclass: "code highlight js-syntax-highlight #{lexer.tag}"
     )
     formatter.format(lexer.lex(code))
   end
diff --git a/spec/features/markdown_spec.rb b/spec/features/markdown_spec.rb
index 3da4dfc2b23..d32bd4adb52 100644
--- a/spec/features/markdown_spec.rb
+++ b/spec/features/markdown_spec.rb
@@ -224,8 +224,4 @@ describe 'GitLab Markdown', feature: true do
   def current_user
     @feat.user
   end
-
-  def user_color_scheme_class
-    :white
-  end
 end
diff --git a/spec/helpers/preferences_helper_spec.rb b/spec/helpers/preferences_helper_spec.rb
index d814b562113..b4dee272bfd 100644
--- a/spec/helpers/preferences_helper_spec.rb
+++ b/spec/helpers/preferences_helper_spec.rb
@@ -48,25 +48,4 @@ describe PreferencesHelper do
       ]
     end
   end
-
-  describe 'user_color_scheme_class' do
-    context 'with current_user is nil' do
-      it 'should return a string' do
-        allow(self).to receive(:current_user).and_return(nil)
-        expect(user_color_scheme_class).to be_kind_of(String)
-      end
-    end
-
-    context 'with a current_user' do
-      (1..5).each do |color_scheme_id|
-        context "with color_scheme_id == #{color_scheme_id}" do
-          it 'should return a string' do
-            current_user = double(color_scheme_id: color_scheme_id)
-            allow(self).to receive(:current_user).and_return(current_user)
-            expect(user_color_scheme_class).to be_kind_of(String)
-          end
-        end
-      end
-    end
-  end
 end