Add ability to remove the time spent through the `remove_time_spent` command.

app/models/concerns/time_trackable.rb

@@ -17,7 +17,9 @@ module TimeTrackable
   def spend_time=(seconds)
     return unless seconds
 
-    timelogs.new(time_spent: seconds)
+    new_time_spent = seconds.zero? ? -(total_time_spent) : seconds
+    timelogs.new(time_spent: new_time_spent)
+
     @time_spent = seconds
   end
 

app/services/slash_commands/interpret_service.rb

@@ -284,6 +284,15 @@ module SlashCommands
       @updates[:time_estimate] = 0
     end
 
+    desc 'Remove the time spent'
+    condition do
+      issuable.persisted? &&
+        current_user.can?(:"admin_#{issuable.to_ability_name}", project)
+    end
+    command :remove_time_spent do
+      @updates[:spend_time] = 0
+    end
+
     def find_label_ids(labels_param)
       label_ids_by_reference = extract_references(labels_param, :label).map(&:id)
       labels_ids_by_name = LabelsFinder.new(current_user, project_id: project.id, name: labels_param.split).execute.select(:id)

app/services/system_note_service.rb

@@ -150,9 +150,14 @@ module SystemNoteService
 
   def change_time_spent(noteable, project, author)
     time_spent  = noteable.time_spent
-    parsed_time = ChronicDuration.output(time_spent.abs, format: :short)
-    action      = time_spent > 0 ? 'Added' : 'Substracted'
-    body        = "#{action} #{parsed_time} of time spent on this #{noteable.human_class_name}"
+
+    if time_spent.zero?
+      body = "Removed time spent on this #{noteable.human_class_name}"
+    else
+      parsed_time = ChronicDuration.output(time_spent.abs, format: :short)
+      action = time_spent > 0 ? 'Added' : 'Substracted'
+      body = "#{action} #{parsed_time} of time spent on this #{noteable.human_class_name}"
+    end
 
     create_note(noteable: noteable, project: project, author: author, note: body)
   end

doc/user/project/slash_commands.md

@@ -32,3 +32,4 @@ do.
 | <code>/estimate &lt;1w 3d 2h 14m&gt;</code> | Set time estimate |
 | `/remove_estimation`       | Remove estimated time |
 | <code>/spend &lt;1h 30m &#124; -1h 5m&gt;</code> | Add or substract spent time |
+| `/remove_time_spent`       | Remove time spent |

spec/services/slash_commands/interpret_service_spec.rb

@@ -234,6 +234,14 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
+    shared_examples 'remove_time_spent command' do
+      it 'populates spend_time: "0" if content contains /remove_time_spent' do
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(spend_time: 0)
+      end
+    end
+
     shared_examples 'empty command' do
       it 'populates {} if content contains an unsupported command' do
         _, updates = service.execute(content, issuable)
@@ -510,6 +518,11 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { issue }
     end
 
+    it_behaves_like 'remove_time_spent command' do
+      let(:content) { '/remove_time_spent' }
+      let(:issuable) { issue }
+    end
+
     context 'when current_user cannot :admin_issue' do
       let(:visitor) { create(:user) }
       let(:issue) { create(:issue, project: project, author: visitor) }