Add ignore white space option in merge request diff

fix this issue(https://gitlab.com/gitlab-org/gitlab-ce/issues/1393).

Add ignore whitespace optoin to Commits Compare view

5 files changed, 21 insertions, 6 deletions

diff --git a/app/controllers/projects/compare_controller.rb b/app/controllers/projects/compare_controller.rb
index 71aaad1fad6..55134e11d15 100644
--- a/app/controllers/projects/compare_controller.rb
+++ b/app/controllers/projects/compare_controller.rb
@@ -12,9 +12,10 @@ class Projects::CompareController < Projects::ApplicationController
   def show
     base_ref = Addressable::URI.unescape(params[:from])
     @ref = head_ref = Addressable::URI.unescape(params[:to])
+    diff_options = { ignore_whitespace_change: true } if params[:w] == '1'
 
     compare_result = CompareService.new.
-      execute(@project, head_ref, @project, base_ref)
+      execute(@project, head_ref, @project, base_ref, diff_options)
 
     if compare_result
       @commits = Commit.decorate(compare_result.commits, @project)
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index 85f37e49e62..e81d65c2330 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -40,7 +40,7 @@ class MergeRequest < ActiveRecord::Base
   after_create :create_merge_request_diff
   after_update :update_merge_request_diff
 
-  delegate :commits, :diffs, to: :merge_request_diff, prefix: nil
+  delegate :commits, :diffs, :diffs_no_whitespace, to: :merge_request_diff, prefix: nil
 
   # When this attribute is true some MR validation is ignored
   # It allows us to close or modify broken merge requests
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index 6575d0bc81f..c499a4b5b4c 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -19,7 +19,7 @@ class MergeRequestDiff < ActiveRecord::Base
   # Prevent store of diff if commits amount more then 500
   COMMITS_SAFE_SIZE = 500
 
-  attr_reader :commits, :diffs
+  attr_reader :commits, :diffs, :diffs_no_whitespace
 
   belongs_to :merge_request
 
@@ -47,6 +47,20 @@ class MergeRequestDiff < ActiveRecord::Base
     @diffs ||= (load_diffs(st_diffs) || [])
   end
 
+  def diffs_no_whitespace
+    # Get latest sha of branch from source project
+    source_sha = merge_request.source_project.commit(source_branch).sha
+
+    compare_result = Gitlab::CompareResult.new(
+      Gitlab::Git::Compare.new(
+        merge_request.target_project.repository.raw_repository,
+        merge_request.target_branch,
+        source_sha,
+      ), { ignore_whitespace_change: true }
+    )
+    @diffs_no_whitespace ||= load_diffs(dump_commits(compare_result.diffs))
+  end
+
   def commits
     @commits ||= load_commits(st_commits || [])
   end
diff --git a/app/services/compare_service.rb b/app/services/compare_service.rb
index bfe6a3dc4be..ec581658fc1 100644
--- a/app/services/compare_service.rb
+++ b/app/services/compare_service.rb
@@ -3,7 +3,7 @@ require 'securerandom'
 # Compare 2 branches for one repo or between repositories
 # and return Gitlab::CompareResult object that responds to commits and diffs
 class CompareService
-  def execute(source_project, source_branch, target_project, target_branch)
+  def execute(source_project, source_branch, target_project, target_branch, diff_options = {})
     source_commit = source_project.commit(source_branch)
     return unless source_commit
 
@@ -25,7 +25,7 @@ class CompareService
         target_project.repository.raw_repository,
         target_branch,
         source_sha,
-      )
+      ), diff_options
     )
   end
 end
diff --git a/app/views/projects/merge_requests/show/_diffs.html.haml b/app/views/projects/merge_requests/show/_diffs.html.haml
index 626970f39be..d9cfc3d7ae9 100644
--- a/app/views/projects/merge_requests/show/_diffs.html.haml
+++ b/app/views/projects/merge_requests/show/_diffs.html.haml
@@ -1,5 +1,5 @@
 - if @merge_request_diff.collected?
-  = render "projects/diffs/diffs", diffs: @merge_request.diffs, project: @merge_request.project
+  = render "projects/diffs/diffs", diffs: params[:w] == '1' ? @merge_request.diffs_no_whitespace : @merge_request.diffs, project: @merge_request.project
 - elsif @merge_request_diff.empty?
   .nothing-here-block Nothing to merge from #{@merge_request.source_branch} into #{@merge_request.target_branch}
 - else