Fix time tracking parsing of months

Patches ChronicDuration to use our custom conversions
when parsing months

changelogs/unreleased/59729-estimate-quick-action-does-not-produce-correct-time-for-1mo.yml

+---
+title: Fix parsing of months in time tracking commands
+merge_request: 32165
+author:
+type: fixed

config/initializers/chronic_duration.rb

+# frozen_string_literal: true
+
 ChronicDuration.raise_exceptions = true
+
+ChronicDuration.prepend Gitlab::Patch::ChronicDuration

lib/gitlab/patch/chronic_duration.rb

+# frozen_string_literal: true
+
+# Fixes a bug where parsing months doesn't take into account
+# the ChronicDuration.days_per_week setting
+#
+# We can remove this when we do a refactor and push upstream in
+# https://gitlab.com/gitlab-org/gitlab-ce/issues/66637
+
+module Gitlab
+  module Patch
+    module ChronicDuration
+      extend ActiveSupport::Concern
+
+      class_methods do
+        def duration_units_seconds_multiplier(unit)
+          return 0 unless duration_units_list.include?(unit)
+
+          case unit
+          when 'months'
+            3600 * ::ChronicDuration.hours_per_day * ::ChronicDuration.days_per_month
+          else
+            super
+          end
+        end
+
+        # ChronicDuration#output uses 1mo = 4w as the conversion so we do the same here.
+        # We do need to add a special case for the default days_per_week value because
+        # we want to retain existing behavior for the default case
+        def days_per_month
+          ::ChronicDuration.days_per_week == 7 ? 30 : ::ChronicDuration.days_per_week * 4
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/patch/chronic_duration_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Patch::ChronicDuration do
+  subject { ChronicDuration.parse('1mo') }
+
+  it 'uses default conversions' do
+    expect(subject).to eq(2_592_000)
+  end
+
+  context 'with custom conversions' do
+    before do
+      ChronicDuration.hours_per_day = 8
+      ChronicDuration.days_per_week = 5
+    end
+
+    after do
+      ChronicDuration.hours_per_day = 24
+      ChronicDuration.days_per_week = 7
+    end
+
+    it 'uses custom conversions' do
+      expect(subject).to eq(576_000)
+    end
+  end
+end

spec/lib/gitlab/time_tracking_formatter_spec.rb

@@ -17,6 +17,14 @@ describe Gitlab::TimeTrackingFormatter do
 
       it { expect(subject).to eq(-12_000) }
     end
+
+    context 'durations with months' do
+      let(:duration_string) { '1mo' }
+
+      it 'uses our custom conversions' do
+        expect(subject).to eq(576_000)
+      end
+    end
   end
 
   describe '#output' do