Add system note when time spent for Issue/MergeRequest has changed.

app/services/issuable_base_service.rb

@@ -41,6 +41,11 @@ class IssuableBaseService < BaseService
       issuable, issuable.project, current_user, issuable.time_estimate)
   end
 
+  def create_time_spent_note(issuable, time_spent)
+    SystemNoteService.change_time_spent(
+      issuable, issuable.project, current_user, time_spent)
+  end
+
   def filter_params(issuable_ability_name = :issue)
     filter_assignee
     filter_milestone
@@ -235,13 +240,15 @@ class IssuableBaseService < BaseService
   end
 
   def change_spent_time(issuable)
-    time_spent = params.delete(:time_spent)
-
     if time_spent
       issuable.timelogs.new(time_spent: time_spent)
     end
   end
 
+  def time_spent
+    @time_spent ||= params.delete(:time_spent)
+  end
+
   def has_changes?(issuable, old_labels: [])
     valid_attrs = [:title, :description, :assignee_id, :milestone_id, :target_branch]
 
@@ -263,6 +270,14 @@ class IssuableBaseService < BaseService
       create_task_status_note(issuable)
     end
 
+    if issuable.previous_changes.include?('time_estimate')
+      create_time_estimate_note(issuable)
+    end
+
+    if time_spent
+      create_time_spent_note(issuable, time_spent)
+    end
+
     create_labels_note(issuable, old_labels) if issuable.labels != old_labels
   end
 end

app/services/issues/update_service.rb

@@ -28,10 +28,6 @@ module Issues
         create_confidentiality_note(issue)
       end
 
-      if issue.previous_changes.include?('time_estimate')
-        create_time_estimate_note(issue)
-      end
-
       added_labels = issue.labels - old_labels
       if added_labels.present?
         notification_service.relabeled_issue(issue, added_labels, current_user)

app/services/slash_commands/interpret_service.rb

@@ -254,11 +254,7 @@ module SlashCommands
       current_user.can?(:"admin_#{issuable.to_ability_name}", project)
     end
     command :estimate do |raw_duration|
-      begin
       @updates[:time_estimate] = ChronicDuration.parse(raw_duration, default_unit: 'hours')
-      rescue ChronicDuration::DurationParseError
-        # do nothing
-      end
     end
 
     desc 'Enter current spent time'
@@ -268,15 +264,11 @@ module SlashCommands
         current_user.can?(:"update_#{issuable.to_ability_name}", issuable)
     end
     command :spend do |raw_duration|
-      begin
       reduce_time = raw_duration.gsub!(/\A-/, '')
       time_spent  = ChronicDuration.parse(raw_duration, default_unit: 'hours')
       time_spent  = time_spent * -1 if reduce_time
 
       @updates[:time_spent] = time_spent
-      rescue ChronicDuration::DurationParseError
-        # do nothing
-      end
     end
 
     def find_label_ids(labels_param)

app/services/system_note_service.rb

@@ -116,7 +116,7 @@ module SystemNoteService
   # noteable      - Noteable object
   # project       - Project owning noteable
   # author        - User performing the change
-  # milestone - Milestone being assigned, or nil
+  # time_estimate - Estimated time
   #
   # Example Note text:
   #
@@ -131,6 +131,26 @@ module SystemNoteService
     create_note(noteable: noteable, project: project, author: author, note: body)
   end
 
+  # Called when the spent time of a Noteable is changed
+  #
+  # noteable   - Noteable object
+  # project    - Project owning noteable
+  # author     - User performing the change
+  # time_spent - Spent time
+  #
+  # Example Note text:
+  #
+  #   "Added 2h 30m of time spent on this issue"
+  #
+  # Returns the created Note object
+
+  def change_time_spent(noteable, project, author, time_spent)
+    parsed_time = ChronicDuration.output(time_spent, format: :short)
+    body = "Added #{parsed_time} of time spent on this #{noteable.to_ability_name}"
+
+    create_note(noteable: noteable, project: project, author: author, note: body)
+  end
+
   # Called when the status of a Noteable is changed
   #
   # noteable - Noteable object