Simplify check for running job on Redis

app/models/merge_request.rb

@@ -396,7 +396,7 @@ class MergeRequest < ActiveRecord::Base
   end
   def merge_ongoing?
-    !!merge_jid && !merged? && Gitlab::SidekiqStatus.num_running([merge_jid]) > 0
+    !!merge_jid && !merged? && Gitlab::SidekiqStatus.running?(merge_jid)
   end
   def closed_without_fork?

lib/gitlab/sidekiq_status.rb

@@ -51,6 +51,13 @@ module Gitlab
       self.num_running(job_ids).zero?
     end
+    # Returns true if the given job is running
+    #
+    # job_id - The Sidekiq job ID to check.
+    def self.running?(job_id)
+      num_running([job_id]) > 0
+    end
+
     # Returns the number of jobs that are running.
     #
     # job_ids - The Sidekiq job IDs to check.

spec/lib/gitlab/sidekiq_status_spec.rb

@@ -39,6 +39,18 @@ describe Gitlab::SidekiqStatus do
     end
   end
+  describe '.running?', :clean_gitlab_redis_shared_state do
+    it 'returns true if job is running' do
+      described_class.set('123')
+
+      expect(described_class.running?('123')).to be(true)
+    end
+
+    it 'returns false if job is not found' do
+      expect(described_class.running?('123')).to be(false)
+    end
+  end
+
   describe '.num_running', :clean_gitlab_redis_shared_state do
     it 'returns 0 if all jobs have been completed' do
       expect(described_class.num_running(%w(123))).to eq(0)

spec/models/merge_request_spec.rb

@@ -1462,7 +1462,7 @@ describe MergeRequest do
   describe '#merge_ongoing?' do
     it 'returns true when merge_id, MR is not merged and it has no running job' do
       merge_request = build_stubbed(:merge_request, state: :open, merge_jid: 'foo')
-      allow(Gitlab::SidekiqStatus).to receive(:num_running).with(['foo']) { 1 }
+      allow(Gitlab::SidekiqStatus).to receive(:running?).with('foo') { true }
       expect(merge_request.merge_ongoing?).to be(true)
     end
@@ -1481,7 +1481,7 @@ describe MergeRequest do
     it 'returns false if there is no merge job running' do
       merge_request = build_stubbed(:merge_request, state: :open, merge_jid: 'foo')
-      allow(Gitlab::SidekiqStatus).to receive(:num_running).with(['foo']) { 0 }
+      allow(Gitlab::SidekiqStatus).to receive(:running?).with('foo') { false }
       expect(merge_request.merge_ongoing?).to be(false)
     end