Add documentation for allowing maintainers to push

app/views/shared/issuable/form/_contribution.html.haml

@@ -15,5 +15,6 @@
       = form.label :allow_maintainer_to_push do
         = form.check_box :allow_maintainer_to_push, disabled: !issuable.can_allow_maintainer_to_push?(current_user)
         = _('Allow edits from maintainers')
+        = link_to 'About this feature', help_page_path('user/project/merge_requests/maintainer_access')
         .help-block
           = allow_maintainer_push_unavailable_reason(issuable)

doc/api/merge_requests.md

@@ -541,7 +541,7 @@ POST /projects/:id/merge_requests
 | `labels`                   | string  | no       | Labels for MR as a comma-separated list                                         |
 | `milestone_id`             | integer | no       | The ID of a milestone                                                           |
 | `remove_source_branch`     | boolean | no       | Flag indicating if a merge request should remove the source branch when merging |
-| `allow_maintainer_to_push` | boolean | no       | Wether or not a maintainer of the target project can push to the source branch  |
+| `allow_maintainer_to_push` | boolean | no       | Whether or not a maintainer of the target project can push to the source branch  |
 
 ```json
 {
@@ -628,7 +628,7 @@ PUT /projects/:id/merge_requests/:merge_request_iid
 | `state_event`              | string  | no       | New state (close/reopen)                                                        |
 | `remove_source_branch`     | boolean | no       | Flag indicating if a merge request should remove the source branch when merging |
 | `discussion_locked`        | boolean | no       | Flag indicating if the merge request's discussion is locked. If the discussion is locked only project members can add, edit or resolve comments. |
-| `allow_maintainer_to_push` | boolean | no       | Wether or not a maintainer of the target project can push to the source branch |
+| `allow_maintainer_to_push` | boolean | no       | Whether or not a maintainer of the target project can push to the source branch |
 
 Must include at least one non-required attribute from above.
 

doc/user/project/merge_requests/index.md

@@ -28,6 +28,7 @@ With GitLab merge requests, you can:
 - Enable [fast-forward merge requests](#fast-forward-merge-requests)
 - Enable [semi-linear history merge requests](#semi-linear-history-merge-requests) as another security layer to guarantee the pipeline is passing in the target branch
 - [Create new merge requests by email](#create-new-merge-requests-by-email)
+- Allow maintainers of the target project to push directly to the fork by [allowing edits from maintainers](maintainer_access.md)
 
 With **[GitLab Enterprise Edition][ee]**, you can also:
 

doc/user/project/merge_requests/maintainer_access.md

+# Allow maintainer pushes for merge requests accross forks
+
+This feature is available for merge requests across forked projects that are
+publicly accessible. It makes it easier for maintainers of projects to collaborate
+on merge requests across forks.
+
+When enabling this feature for a merge request, you give can give members with push access to the target project rights to edit files on the source branch of the merge request.
+
+The feature can only be enabled by users who already have push access to the source project. And only lasts while the merge request is open.
+
+Enable this functionality while creating a merge request:
+
+![Enable maintainer edits](./img/allow_maintainer_push.png)

lib/api/merge_requests.rb

@@ -144,7 +144,7 @@ module API
           optional :milestone_id, type: Integer, desc: 'The ID of a milestone to assign the merge request'
           optional :labels, type: String, desc: 'Comma-separated list of label names'
           optional :remove_source_branch, type: Boolean, desc: 'Remove source branch when merging'
-          optional :allow_maintainer_to_push, type: Boolean, desc: 'Wether a maintainer of the target project can push to the source project'
+          optional :allow_maintainer_to_push, type: Boolean, desc: 'Whether a maintainer of the target project can push to the source project'
 
           use :optional_params_ee
         end