Merge branch '18755-fix-destroy-project-causes-post_decline_request-to-be-executed' into 'master'

Resolve "Destroying a project causes post_decline_request to be executed"

## What does this MR do?

Ensure we don't send "access request declined" to access requesters when a project is deleted.

## Are there points in the code the reviewer needs to double check?

I've created a service to decouple the notification sending from the AR model.

## Why was this MR needed?

Because there was an issue.

## What are the relevant issue numbers?

Fixes #18755, #18750.

## Does this MR meet the acceptance criteria?

- [x] No CHANGELOG needed.
- [x] Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4744

3 files changed, 28 insertions, 21 deletions

diff --git a/app/views/layouts/nav/_group_settings.html.haml b/app/views/layouts/nav/_group_settings.html.haml
index dac46648b9f..3a24b09ab7e 100644
--- a/app/views/layouts/nav/_group_settings.html.haml
+++ b/app/views/layouts/nav/_group_settings.html.haml
@@ -1,16 +1,22 @@
 - if current_user
-  - if access = @group.users.find_by(id: current_user.id)
-    .controls
-      .dropdown.group-settings-dropdown
-        %a.dropdown-new.btn.btn-default#group-settings-button{href: '#', 'data-toggle' => 'dropdown'}
-          = icon('cog')
-          = icon('caret-down')
-        %ul.dropdown-menu.dropdown-menu-align-right
-          - if can?(current_user, :admin_group, @group)
-            = nav_link(path: 'groups#projects') do
-              = link_to projects_group_path(@group), title: 'Projects' do
-                Projects
-            %li.divider
-            %li
-              = link_to edit_group_path(@group) do
-                Edit Group
+  - can_edit = can?(current_user, :admin_group, @group)
+  - member = @group.members.non_request.find_by(user_id: current_user.id)
+  - can_leave = member && can?(current_user, :destroy_group_member, member)
+
+  .controls
+    .dropdown.group-settings-dropdown
+      %a.dropdown-new.btn.btn-default#group-settings-button{href: '#', 'data-toggle' => 'dropdown'}
+        = icon('cog')
+        = icon('caret-down')
+      %ul.dropdown-menu.dropdown-menu-align-right
+        = nav_link(path: 'groups#projects') do
+          = link_to 'Projects', projects_group_path(@group), title: 'Projects'
+        %li.divider
+        - if can_edit
+          %li
+            = link_to 'Edit Group', edit_group_path(@group)
+        - if can_leave
+          %li
+            = link_to polymorphic_path([:leave, @group, :members]),
+              data: { confirm: leave_confirmation_message(@group) }, method: :delete, title: 'Leave group' do
+              Leave Group
diff --git a/app/views/layouts/nav/_project.html.haml b/app/views/layouts/nav/_project.html.haml
index 7762746f848..27e840df503 100644
--- a/app/views/layouts/nav/_project.html.haml
+++ b/app/views/layouts/nav/_project.html.haml
@@ -5,19 +5,20 @@
         = icon('cog')
         = icon('caret-down')
       %ul.dropdown-menu.dropdown-menu-align-right
-        - is_project_member = @project.users.exists?(current_user.id)
-        - access = @project.team.max_member_access(current_user.id)
         - can_edit = can?(current_user, :admin_project, @project)
+        -# We don't use @project.team.find_member because it searches for group members too...
+        - member = @project.members.non_request.find_by(user_id: current_user.id)
+        - can_leave = member && can?(current_user, :destroy_project_member, member)
 
-        = render 'layouts/nav/project_settings', access: access, can_edit: can_edit
+        = render 'layouts/nav/project_settings', can_edit: can_edit
 
-        - if can_edit || is_project_member
+        - if can_edit || can_leave
           %li.divider
           - if can_edit
             %li
               = link_to edit_project_path(@project) do
                 Edit Project
-          - if is_project_member
+          - if can_leave
             %li
               = link_to polymorphic_path([:leave, @project, :members]),
                 data: { confirm: leave_confirmation_message(@project) }, method: :delete, title: 'Leave project' do
diff --git a/app/views/layouts/nav/_project_settings.html.haml b/app/views/layouts/nav/_project_settings.html.haml
index 13d32bd1354..51a54b4f262 100644
--- a/app/views/layouts/nav/_project_settings.html.haml
+++ b/app/views/layouts/nav/_project_settings.html.haml
@@ -3,7 +3,7 @@
     = link_to namespace_project_project_members_path(@project.namespace, @project), title: 'Members', class: 'team-tab tab' do
       %span
         Members
-- if access && can_edit
+- if can_edit
   - if @project.allowed_to_share_with_group?
     = nav_link(controller: :group_links) do
       = link_to namespace_project_group_links_path(@project.namespace, @project), title: "Groups" do