Support title and desc on merge w/ push optionlabel-descr-push-opts

MergeRequests::PushOptionsHandlerService has been updated to allow
creating and updating merge requests with the `title` and
`description` set using git push options.

To create a new merge request and set its title and description:

      git push -u origin -o merge_request.create \
        -o merge_request.title="My title" \
        -o merge_request.description="My description"

To update an existing merge request and set its title and
description:

      git push -u origin -o merge_request.title="My title" \
        -o merge_request.description="My description"

Issue https://gitlab.com/gitlab-org/gitlab-ce/issues/64320

5 files changed, 194 insertions, 10 deletions

diff --git a/app/services/merge_requests/push_options_handler_service.rb b/app/services/merge_requests/push_options_handler_service.rb
index 6d70b5106c7..b210004e6e1 100644
--- a/app/services/merge_requests/push_options_handler_service.rb
+++ b/app/services/merge_requests/push_options_handler_service.rb
@@ -118,7 +118,14 @@ module MergeRequests
     end
 
     def base_params
-      params = {}
+      params = {
+        title: push_options[:title],
+        description: push_options[:description],
+        target_branch: push_options[:target],
+        force_remove_source_branch: push_options[:remove_source_branch]
+      }
+
+      params.compact!
 
       if push_options.key?(:merge_when_pipeline_succeeds)
         params.merge!(
@@ -127,14 +134,6 @@ module MergeRequests
         )
       end
 
-      if push_options.key?(:remove_source_branch)
-        params[:force_remove_source_branch] = push_options[:remove_source_branch]
-      end
-
-      if push_options.key?(:target)
-        params[:target_branch] = push_options[:target]
-      end
-
       params
     end
 
diff --git a/changelogs/unreleased/label-descr-push-opts.yml b/changelogs/unreleased/label-descr-push-opts.yml
new file mode 100644
index 00000000000..9b01cfdaed2
--- /dev/null
+++ b/changelogs/unreleased/label-descr-push-opts.yml
@@ -0,0 +1,5 @@
+---
+title: Support setting of merge request title and description using git push options
+merge_request: 31068
+author:
+type: added
diff --git a/doc/user/project/merge_requests/index.md b/doc/user/project/merge_requests/index.md
index d5ca853eff5..f78ec9d96e6 100644
--- a/doc/user/project/merge_requests/index.md
+++ b/doc/user/project/merge_requests/index.md
@@ -343,6 +343,30 @@ git push -o merge_request.remove_source_branch
 You can also use this push option in addition to the
 `merge_request.create` push option.
 
+### Set merge request title using git push options
+
+To set the title of an existing merge request, use
+the `merge_request.title` push option:
+
+```sh
+git push -o merge_request.title="The title I want"
+```
+
+You can also use this push option in addition to the
+`merge_request.create` push option.
+
+### Set merge request description using git push options
+
+To set the description of an existing merge request, use
+the `merge_request.description` push option:
+
+```sh
+git push -o merge_request.description="The description I want"
+```
+
+You can also use this push option in addition to the
+`merge_request.create` push option.
+
 ## Find the merge request that introduced a change
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab-ce/issues/2383) in GitLab 10.5.
diff --git a/lib/gitlab/push_options.rb b/lib/gitlab/push_options.rb
index b96590af08e..682edfc4259 100644
--- a/lib/gitlab/push_options.rb
+++ b/lib/gitlab/push_options.rb
@@ -6,9 +6,11 @@ module Gitlab
       merge_request: {
         keys: [
           :create,
+          :description,
           :merge_when_pipeline_succeeds,
           :remove_source_branch,
-          :target
+          :target,
+          :title
         ]
       },
       ci: {
diff --git a/spec/services/merge_requests/push_options_handler_service_spec.rb b/spec/services/merge_requests/push_options_handler_service_spec.rb
index ac40cf02c48..a27fea0c90f 100644
--- a/spec/services/merge_requests/push_options_handler_service_spec.rb
+++ b/spec/services/merge_requests/push_options_handler_service_spec.rb
@@ -11,6 +11,8 @@ describe MergeRequests::PushOptionsHandlerService do
   let(:service) { described_class.new(project, user, changes, push_options) }
   let(:source_branch) { 'fix' }
   let(:target_branch) { 'feature' }
+  let(:title) { 'my title' }
+  let(:description) { 'my description' }
   let(:new_branch_changes) { "#{Gitlab::Git::BLANK_SHA} 570e7b2abdd848b95f2f578043fc23bd6f6fd24d refs/heads/#{source_branch}" }
   let(:existing_branch_changes) { "d14d6c0abdd253381df51a723d58691b2ee1ab08 570e7b2abdd848b95f2f578043fc23bd6f6fd24d refs/heads/#{source_branch}" }
   let(:deleted_branch_changes) { "d14d6c0abdd253381df51a723d58691b2ee1ab08 #{Gitlab::Git::BLANK_SHA} refs/heads/#{source_branch}" }
@@ -73,6 +75,26 @@ describe MergeRequests::PushOptionsHandlerService do
     end
   end
 
+  shared_examples_for 'a service that can set the title of a merge request' do
+    subject(:last_mr) { MergeRequest.last }
+
+    it 'sets the title' do
+      service.execute
+
+      expect(last_mr.title).to eq(title)
+    end
+  end
+
+  shared_examples_for 'a service that can set the description of a merge request' do
+    subject(:last_mr) { MergeRequest.last }
+
+    it 'sets the description' do
+      service.execute
+
+      expect(last_mr.description).to eq(description)
+    end
+  end
+
   shared_examples_for 'a service that can set the merge request to merge when pipeline succeeds' do
     subject(:last_mr) { MergeRequest.last }
 
@@ -350,6 +372,138 @@ describe MergeRequests::PushOptionsHandlerService do
     end
   end
 
+  describe '`title` push option' do
+    let(:push_options) { { title: title } }
+
+    context 'with a new branch' do
+      let(:changes) { new_branch_changes }
+
+      it_behaves_like 'a service that does not create a merge request'
+
+      it 'adds an error to the service' do
+        error = "A merge_request.create push option is required to create a merge request for branch #{source_branch}"
+
+        service.execute
+
+        expect(service.errors).to include(error)
+      end
+
+      context 'when coupled with the `create` push option' do
+        let(:push_options) { { create: true, title: title } }
+
+        it_behaves_like 'a service that can create a merge request'
+        it_behaves_like 'a service that can set the title of a merge request'
+      end
+    end
+
+    context 'with an existing branch but no open MR' do
+      let(:changes) { existing_branch_changes }
+
+      it_behaves_like 'a service that does not create a merge request'
+
+      it 'adds an error to the service' do
+        error = "A merge_request.create push option is required to create a merge request for branch #{source_branch}"
+
+        service.execute
+
+        expect(service.errors).to include(error)
+      end
+
+      context 'when coupled with the `create` push option' do
+        let(:push_options) { { create: true, title: title } }
+
+        it_behaves_like 'a service that can create a merge request'
+        it_behaves_like 'a service that can set the title of a merge request'
+      end
+    end
+
+    context 'with an existing branch that has a merge request open' do
+      let(:changes) { existing_branch_changes }
+      let!(:merge_request) { create(:merge_request, source_project: project, source_branch: source_branch)}
+
+      it_behaves_like 'a service that does not create a merge request'
+      it_behaves_like 'a service that can set the title of a merge request'
+    end
+
+    context 'with a deleted branch' do
+      let(:changes) { deleted_branch_changes }
+
+      it_behaves_like 'a service that does nothing'
+    end
+
+    context 'with the project default branch' do
+      let(:changes) { default_branch_changes }
+
+      it_behaves_like 'a service that does nothing'
+    end
+  end
+
+  describe '`description` push option' do
+    let(:push_options) { { description: description } }
+
+    context 'with a new branch' do
+      let(:changes) { new_branch_changes }
+
+      it_behaves_like 'a service that does not create a merge request'
+
+      it 'adds an error to the service' do
+        error = "A merge_request.create push option is required to create a merge request for branch #{source_branch}"
+
+        service.execute
+
+        expect(service.errors).to include(error)
+      end
+
+      context 'when coupled with the `create` push option' do
+        let(:push_options) { { create: true, description: description } }
+
+        it_behaves_like 'a service that can create a merge request'
+        it_behaves_like 'a service that can set the description of a merge request'
+      end
+    end
+
+    context 'with an existing branch but no open MR' do
+      let(:changes) { existing_branch_changes }
+
+      it_behaves_like 'a service that does not create a merge request'
+
+      it 'adds an error to the service' do
+        error = "A merge_request.create push option is required to create a merge request for branch #{source_branch}"
+
+        service.execute
+
+        expect(service.errors).to include(error)
+      end
+
+      context 'when coupled with the `create` push option' do
+        let(:push_options) { { create: true, description: description } }
+
+        it_behaves_like 'a service that can create a merge request'
+        it_behaves_like 'a service that can set the description of a merge request'
+      end
+    end
+
+    context 'with an existing branch that has a merge request open' do
+      let(:changes) { existing_branch_changes }
+      let!(:merge_request) { create(:merge_request, source_project: project, source_branch: source_branch)}
+
+      it_behaves_like 'a service that does not create a merge request'
+      it_behaves_like 'a service that can set the description of a merge request'
+    end
+
+    context 'with a deleted branch' do
+      let(:changes) { deleted_branch_changes }
+
+      it_behaves_like 'a service that does nothing'
+    end
+
+    context 'with the project default branch' do
+      let(:changes) { default_branch_changes }
+
+      it_behaves_like 'a service that does nothing'
+    end
+  end
+
   describe 'multiple pushed branches' do
     let(:push_options) { { create: true } }
     let(:changes) do