Merge branch 'master' into 38869-datetime

* master: (112 commits)
  small change to make less conflict with EE version
  Add cop for use of remove_column
  Resolve merge conflicts with dev.gitlab.org/master after security release
  add index for doc/administration/operations/
  Remove RubySampler#sample_objects for performance as well
  Bugfix: User can't change the access level of an access requester
  Add spec for removing issues.assignee_id
  updated imports
  Keep track of storage check timings
  Remove a header level in the new 'Automatic CE->EE merge' doc
  Improve down step of removing issues.assignee_id column
  Fix specs after removing assignee_id field
  Remove issues.assignee_id column
  Resolve conflicts in app/models/user.rb
  Fix image view mode
  Do not raise when downstream pipeline is created
  Remove the need for destroy and add a comment in the spec
  Use build instead of create in importer spec
  Simplify normalizing of paths
  Remove allocation tracking code from InfluxDB sampler for performance
  ...

7 files changed, 55 insertions, 41 deletions

diff --git a/app/views/projects/merge_requests/_commits.html.haml b/app/views/projects/merge_requests/_commits.html.haml
index 11793919ff7..b414518b597 100644
--- a/app/views/projects/merge_requests/_commits.html.haml
+++ b/app/views/projects/merge_requests/_commits.html.haml
@@ -5,4 +5,4 @@
     = custom_icon ('illustration_no_commits')
 - else
   %ol#commits-list.list-unstyled
-    = render "projects/commits/commits", project: @merge_request.source_project, ref: @merge_request.source_branch
+    = render "projects/commits/commits", merge_request: @merge_request
diff --git a/app/views/projects/merge_requests/diffs/_commit_widget.html.haml b/app/views/projects/merge_requests/diffs/_commit_widget.html.haml
new file mode 100644
index 00000000000..2e5594f8cbe
--- /dev/null
+++ b/app/views/projects/merge_requests/diffs/_commit_widget.html.haml
@@ -0,0 +1,5 @@
+- if @commit
+  .info-well.hidden-xs.prepend-top-default
+    .well-segment
+      %ul.blob-commit-info
+        = render 'projects/commits/commit', commit: @commit, merge_request: @merge_request, view_details: true
diff --git a/app/views/projects/merge_requests/diffs/_different_base.html.haml b/app/views/projects/merge_requests/diffs/_different_base.html.haml
new file mode 100644
index 00000000000..0e57066f9c9
--- /dev/null
+++ b/app/views/projects/merge_requests/diffs/_different_base.html.haml
@@ -0,0 +1,11 @@
+- if @merge_request_diff && different_base?(@start_version, @merge_request_diff)
+  .mr-version-controls
+    .content-block
+      = icon('info-circle')
+      Selected versions have different base commits.
+      Changes will include
+      = link_to project_compare_path(@project, from: @start_version.base_commit_sha, to: @merge_request_diff.base_commit_sha) do
+        new commits
+      from
+      = succeed '.' do
+        %code.ref-name= @merge_request.target_branch
diff --git a/app/views/projects/merge_requests/diffs/_diffs.html.haml b/app/views/projects/merge_requests/diffs/_diffs.html.haml
index 3d7a8f9d870..60c91024b23 100644
--- a/app/views/projects/merge_requests/diffs/_diffs.html.haml
+++ b/app/views/projects/merge_requests/diffs/_diffs.html.haml
@@ -1,13 +1,18 @@
-- if @merge_request_diff.collected? || @merge_request_diff.overflow?
-  = render 'projects/merge_requests/diffs/versions'
-  = render "projects/diffs/diffs", diffs: @diffs, environment: @environment, merge_request: true
-- elsif @merge_request_diff.empty?
+= render 'projects/merge_requests/diffs/version_controls'
+= render 'projects/merge_requests/diffs/different_base'
+= render 'projects/merge_requests/diffs/not_all_comments_displayed'
+= render 'projects/merge_requests/diffs/commit_widget'
+
+- if @merge_request_diff&.empty?
   .nothing-here-block
     = image_tag 'illustrations/merge_request_changes_empty.svg'
-    %p
-      Nothing to merge from
-      %strong= @merge_request.source_branch
-      into
-      %strong= @merge_request.target_branch
-
+    = succeed '.' do
+      No changes between
+      %span.ref-name= @merge_request.source_branch
+      and
+      %span.ref-name= @merge_request.target_branch
       %p= link_to 'Create commit', project_new_blob_path(@project, @merge_request.source_branch), class: 'btn btn-save'
+- else
+  - diff_viewable = @merge_request_diff ? @merge_request_diff.collected? || @merge_request_diff.overflow? : true
+  - if diff_viewable
+    = render "projects/diffs/diffs", diffs: @diffs, environment: @environment, merge_request: true
diff --git a/app/views/projects/merge_requests/diffs/_not_all_comments_displayed.html.haml b/app/views/projects/merge_requests/diffs/_not_all_comments_displayed.html.haml
new file mode 100644
index 00000000000..529fbb8547a
--- /dev/null
+++ b/app/views/projects/merge_requests/diffs/_not_all_comments_displayed.html.haml
@@ -0,0 +1,17 @@
+- if @commit || @start_version || (@merge_request_diff && !@merge_request_diff.latest?)
+  .mr-version-controls
+    .content-block.comments-disabled-notif.clearfix
+      = icon('info-circle')
+      = succeed '.' do
+        - if @commit
+          Only comments from the following commit are shown below
+        - else
+          Not all comments are displayed because you're
+          - if @start_version
+            comparing two versions of the diff
+          - else
+            viewing an old version of the diff
+      .pull-right
+        = link_to diffs_project_merge_request_path(@merge_request.project, @merge_request), class: 'btn btn-sm' do
+          Show latest version
+          = "of the diff" if @commit
diff --git a/app/views/projects/merge_requests/diffs/_versions.html.haml b/app/views/projects/merge_requests/diffs/_version_controls.html.haml
index 9f7152b9824..1c26f0405d2 100644
--- a/app/views/projects/merge_requests/diffs/_versions.html.haml
+++ b/app/views/projects/merge_requests/diffs/_version_controls.html.haml
@@ -1,4 +1,4 @@
-- if @merge_request_diffs.size > 1
+- if @merge_request_diff && @merge_request_diffs.size > 1
   .mr-version-controls
     .mr-version-menus-container.content-block
       Changes between
@@ -71,27 +71,3 @@
                         (base)
                     %div
                       %strong.commit-sha= short_sha(@merge_request_diff.base_commit_sha)
-
-    - if different_base?(@start_version, @merge_request_diff)
-      .content-block
-        = icon('info-circle')
-        Selected versions have different base commits.
-        Changes will include
-        = link_to project_compare_path(@project, from: @start_version.base_commit_sha, to: @merge_request_diff.base_commit_sha) do
-          new commits
-        from
-        = succeed '.' do
-          %code= @merge_request.target_branch
-
-    - if @start_version || !@merge_request_diff.latest?
-      .comments-disabled-notif.content-block
-        = icon('info-circle')
-        Not all comments are displayed because you're
-        - if @start_version
-          comparing two versions
-        - else
-          viewing an old version
-        of the diff.
-
-        .pull-right
-          = link_to 'Show latest version', diffs_project_merge_request_path(@project, @merge_request), class: 'btn btn-sm'
diff --git a/app/views/projects/merge_requests/show.html.haml b/app/views/projects/merge_requests/show.html.haml
index d88e3d794d3..abff702fd9d 100644
--- a/app/views/projects/merge_requests/show.html.haml
+++ b/app/views/projects/merge_requests/show.html.haml
@@ -8,7 +8,7 @@
   = webpack_bundle_tag('common_vue')
   = webpack_bundle_tag('diff_notes')
 
-.merge-request{ 'data-mr-action': "#{j params[:tab].presence || 'show'}", 'data-url' => merge_request_path(@merge_request, format: :json), 'data-project-path' => project_path(@merge_request.project) }
+.merge-request{ data: { mr_action: j(params[:tab].presence || 'show'), url: merge_request_path(@merge_request, format: :json), project_path: project_path(@merge_request.project) } }
   = render "projects/merge_requests/mr_title"
 
   .merge-request-details.issuable-details{ data: { id: @merge_request.project.id } }
@@ -38,21 +38,21 @@
           .nav-links.scrolling-tabs
             %ul.merge-request-tabs
               %li.notes-tab
-                = link_to project_merge_request_path(@project, @merge_request), data: { target: 'div#notes', action: 'show', toggle: 'tab' } do
+                = tab_link_for @merge_request, :show, force_link: @commit.present? do
                   Discussion
                   %span.badge= @merge_request.related_notes.user.count
               - if @merge_request.source_project
                 %li.commits-tab
-                  = link_to commits_project_merge_request_path(@project, @merge_request), data: { target: 'div#commits', action: 'commits', toggle: 'tab' } do
+                  = tab_link_for @merge_request, :commits do
                     Commits
                     %span.badge= @commits_count
               - if @pipelines.any?
                 %li.pipelines-tab
-                  = link_to pipelines_project_merge_request_path(@project, @merge_request), data: { target: '#pipelines', action: 'pipelines', toggle: 'tab' } do
+                  = tab_link_for @merge_request, :pipelines do
                     Pipelines
                     %span.badge.js-pipelines-mr-count= @pipelines.size
               %li.diffs-tab
-                = link_to diffs_project_merge_request_path(@project, @merge_request), data: { target: 'div#diffs', action: 'diffs', toggle: 'tab' } do
+                = tab_link_for @merge_request, :diffs do
                   Changes
                   %span.badge= @merge_request.diff_size
         #resolve-count-app.line-resolve-all-container.prepend-top-10{ "v-cloak" => true }