Add state events to merge request update mutation

This adds the ability to open and close MRs from GraphQL

app/graphql/mutations/merge_requests/update.rb

@@ -19,9 +19,14 @@ class Update < Base
                required: false,
                description: copy_field_description(Types::MergeRequestType, :description)
-      def resolve(args)
-        merge_request = authorized_find!(**args.slice(:project_path, :iid))
-        attributes = args.slice(:title, :description, :target_branch).compact
+      argument :state, ::Types::MergeRequestStateEventEnum,
+               required: false,
+               as: :state_event,
+               description: 'The action to perform to change the state.'
+
+      def resolve(project_path:, iid:, **args)
+        merge_request = authorized_find!(project_path: project_path, iid: iid)
+        attributes = args.compact
         ::MergeRequests::UpdateService
           .new(merge_request.project, current_user, attributes)

app/graphql/types/merge_request_state_event_enum.rb

+# frozen_string_literal: true
+
+module Types
+  class MergeRequestStateEventEnum < BaseEnum
+    graphql_name 'MergeRequestNewState'
+    description 'New state to apply to a merge request.'
+
+    value 'OPEN',
+      value: 'reopen',
+      description: 'Open the merge request if it is closed.'
+
+    value 'CLOSED',
+      value: 'close',
+      description: 'Close the merge request if it is open.'
+  end
+end

app/models/merge_request.rb

@@ -921,6 +921,10 @@ def reopenable?
     closed? && !source_project_missing? && source_branch_exists?
   end
+  def can_be_closed?
+    opened?
+  end
+
   def ensure_merge_request_diff
     merge_request_diff.persisted? || create_merge_request_diff
   end

changelogs/unreleased/ajk-add-state-events-to-mr-update-mutation.yml

+---
+title: Add state events to merge request update mutation
+merge_request: 54133
+author:
+type: added

doc/api/graphql/reference/gitlab_schema.graphql

@@ -15841,6 +15841,21 @@ Identifier of MergeRequest.
 """
 scalar MergeRequestID
+"""
+New state to apply to a merge request.
+"""
+enum MergeRequestNewState {
+  """
+  Close the merge request if it is open.
+  """
+  CLOSED
+
+  """
+  Open the merge request if it is closed.
+  """
+  OPEN
+}
+
 """
 Check permissions for the current user on a merge request
 """
@@ -16340,6 +16355,11 @@ input MergeRequestUpdateInput {
   """
   projectPath: ID!
+  """
+  The action to perform to change the state.
+  """
+  state: MergeRequestNewState
+
   """
   Target branch of the merge request.
   """

doc/api/graphql/reference/gitlab_schema.json

@@ -43339,6 +43339,29 @@
           "enumValues": null,
           "possibleTypes": null
         },
+        {
+          "kind": "ENUM",
+          "name": "MergeRequestNewState",
+          "description": "New state to apply to a merge request.",
+          "fields": null,
+          "inputFields": null,
+          "interfaces": null,
+          "enumValues": [
+            {
+              "name": "OPEN",
+              "description": "Open the merge request if it is closed.",
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
+            {
+              "name": "CLOSED",
+              "description": "Close the merge request if it is open.",
+              "isDeprecated": false,
+              "deprecationReason": null
+            }
+          ],
+          "possibleTypes": null
+        },
         {
           "kind": "OBJECT",
           "name": "MergeRequestPermissions",
@@ -44668,6 +44691,16 @@
               },
               "defaultValue": null
             },
+            {
+              "name": "state",
+              "description": "The action to perform to change the state.",
+              "type": {
+                "kind": "ENUM",
+                "name": "MergeRequestNewState",
+                "ofType": null
+              },
+              "defaultValue": null
+            },
             {
               "name": "clientMutationId",
               "description": "A unique identifier for the client performing the mutation.",

doc/api/graphql/reference/index.md

@@ -5111,6 +5111,15 @@ Possible identifier types for a measurement.
 | `PROJECTS` | Project count |
 | `USERS` | User count |
+### MergeRequestNewState
+
+New state to apply to a merge request..
+
+| Value | Description |
+| ----- | ----------- |
+| `CLOSED` | Close the merge request if it is open. |
+| `OPEN` | Open the merge request if it is closed. |
+
 ### MergeRequestSort
 Values for sorting merge requests.

spec/graphql/mutations/merge_requests/update_spec.rb

@@ -12,10 +12,11 @@
   describe '#resolve' do
     let(:attributes) { { title: 'new title', description: 'new description', target_branch: 'new-branch' } }
+    let(:arguments) { attributes }
     let(:mutated_merge_request) { subject[:merge_request] }
     subject do
-      mutation.resolve(project_path: merge_request.project.full_path, iid: merge_request.iid, **attributes)
+      mutation.resolve(project_path: merge_request.project.full_path, iid: merge_request.iid, **arguments)
     end
     it_behaves_like 'permission level for merge request mutation is correctly verified'
@@ -61,6 +62,24 @@
           expect(mutated_merge_request).to have_attributes(attributes)
         end
       end
+
+      context 'when closing the MR' do
+        let(:arguments) { { state_event: ::Types::MergeRequestStateEventEnum.values['CLOSED'].value } }
+
+        it 'closes the MR' do
+          expect(mutated_merge_request).to be_closed
+        end
+      end
+
+      context 'when re-opening the MR' do
+        let(:arguments) { { state_event: ::Types::MergeRequestStateEventEnum.values['OPEN'].value } }
+
+        it 'closes the MR' do
+          merge_request.close!
+
+          expect(mutated_merge_request).to be_open
+        end
+      end
     end
   end
 end

spec/graphql/types/merge_request_state_event_enum_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe GitlabSchema.types['MergeRequestNewState'] do
+  it 'has the appropriate values' do
+    expect(described_class.values).to contain_exactly(
+      ['OPEN', have_attributes(value: 'reopen')],
+      ['CLOSED', have_attributes(value: 'close')]
+    )
+  end
+end