Backport changes from EE squash

Backport changes from the EE-only squash implementation, which would
otherwise conflict when merge CE into EE.

<https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1024>

5 files changed, 21 insertions, 12 deletions

diff --git a/app/views/projects/merge_requests/widget/open/_accept.html.haml b/app/views/projects/merge_requests/widget/open/_accept.html.haml
index 7809e9c8c72..39cb0ca9cdc 100644
--- a/app/views/projects/merge_requests/widget/open/_accept.html.haml
+++ b/app/views/projects/merge_requests/widget/open/_accept.html.haml
@@ -35,10 +35,10 @@
           The source branch will be removed.
       - elsif @merge_request.can_remove_source_branch?(current_user)
         .accept-control.checkbox
-          = label_tag :should_remove_source_branch, class: "remove_source_checkbox" do
+          = label_tag :should_remove_source_branch, class: "merge-param-checkbox" do
             = check_box_tag :should_remove_source_branch
             Remove source branch
-      .accept-control.right
+      .accept-control
         = link_to "#", class: "modify-merge-commit-link js-toggle-button" do
           = icon('edit')
           Modify commit message
diff --git a/app/views/projects/merge_requests/widget/open/_merge_when_build_succeeds.html.haml b/app/views/projects/merge_requests/widget/open/_merge_when_build_succeeds.html.haml
index f70cd09c5f4..304b0afcf93 100644
--- a/app/views/projects/merge_requests/widget/open/_merge_when_build_succeeds.html.haml
+++ b/app/views/projects/merge_requests/widget/open/_merge_when_build_succeeds.html.haml
@@ -19,7 +19,7 @@
   - if remove_source_branch_button || user_can_cancel_automatic_merge
     .clearfix.prepend-top-10
       - if remove_source_branch_button
-        = link_to merge_namespace_project_merge_request_path(@merge_request.target_project.namespace, @merge_request.target_project, @merge_request, merge_when_build_succeeds: true, should_remove_source_branch: true, sha: @merge_request.diff_head_sha), remote: true, method: :post, class: "btn btn-grouped btn-primary btn-sm remove_source_branch" do
+        = link_to merge_namespace_project_merge_request_path(@merge_request.target_project.namespace, @merge_request.target_project, @merge_request, merge_params(@merge_request)), remote: true, method: :post, class: "btn btn-grouped btn-primary btn-sm remove_source_branch" do
           = icon('times')
           Remove Source Branch When Merged
 
diff --git a/app/views/shared/issuable/_form.html.haml b/app/views/shared/issuable/_form.html.haml
index 0a4de709fcd..cb92b2e97a7 100644
--- a/app/views/shared/issuable/_form.html.haml
+++ b/app/views/shared/issuable/_form.html.haml
@@ -43,6 +43,8 @@
 
 = render 'shared/issuable/form/branch_chooser', issuable: issuable, form: form
 
+= render 'shared/issuable/form/merge_params', issuable: issuable
+
 - if @merge_request_for_resolving_discussions
   .form-group
     .col-sm-10.col-sm-offset-2
diff --git a/app/views/shared/issuable/form/_branch_chooser.html.haml b/app/views/shared/issuable/form/_branch_chooser.html.haml
index b757893ea04..2793e7bcff4 100644
--- a/app/views/shared/issuable/form/_branch_chooser.html.haml
+++ b/app/views/shared/issuable/form/_branch_chooser.html.haml
@@ -19,12 +19,3 @@
     - if issuable.new_record?
        
       = link_to 'Change branches', mr_change_branches_path(issuable)
-
-- if issuable.can_remove_source_branch?(current_user)
-  .form-group
-    .col-sm-10.col-sm-offset-2
-      .checkbox
-        = label_tag 'merge_request[force_remove_source_branch]' do
-          = hidden_field_tag 'merge_request[force_remove_source_branch]', '0', id: nil
-          = check_box_tag 'merge_request[force_remove_source_branch]', '1', issuable.force_remove_source_branch?
-          Remove source branch when merge request is accepted.
diff --git a/app/views/shared/issuable/form/_merge_params.html.haml b/app/views/shared/issuable/form/_merge_params.html.haml
new file mode 100644
index 00000000000..03309722326
--- /dev/null
+++ b/app/views/shared/issuable/form/_merge_params.html.haml
@@ -0,0 +1,16 @@
+- issuable = local_assigns.fetch(:issuable)
+
+- return unless issuable.is_a?(MergeRequest)
+- return if issuable.closed_without_fork?
+
+-# This check is duplicated below, to avoid conflicts with EE.
+- return unless issuable.can_remove_source_branch?(current_user)
+
+.form-group
+  .col-sm-10.col-sm-offset-2
+    - if issuable.can_remove_source_branch?(current_user)
+      .checkbox
+        = label_tag 'merge_request[force_remove_source_branch]' do
+          = hidden_field_tag 'merge_request[force_remove_source_branch]', '0', id: nil
+          = check_box_tag 'merge_request[force_remove_source_branch]', '1', issuable.force_remove_source_branch?
+          Remove source branch when merge request is accepted.