[OP-19969] Round instead of truncate when formatting a duration from hours

lib/api/v3/utilities/date_time_formatter.rb

@@ -85,7 +85,11 @@ def format_datetime(datetime, allow_nil: false)
         def format_duration_from_hours(hours, allow_nil: false)
           return nil if hours.nil? && allow_nil
 
-          Duration.new(seconds: hours * 3600).iso8601
+          # Duration.new truncates its :seconds argument via Float#to_i
+          # (ruby-duration gem) rather than rounding -- round explicitly
+          # here first so e.g. 3600.9 seconds (1h 0.9s) serializes as
+          # PT1H1S, not silently dropped to PT1H.
+          Duration.new(seconds: (hours * 3600).round).iso8601
         end
 
         def parse_duration_to_hours(duration, property_name, allow_nil: false)
@@ -104,7 +108,11 @@ def parse_duration_to_hours(duration, property_name, allow_nil: false)
         def format_duration_from_days(days, allow_nil: false)
           return nil if days.nil? && allow_nil
 
-          Duration.new(seconds: days * 3600 * 24).iso8601
+          # Duration.new truncates its :seconds argument via Float#to_i
+          # (ruby-duration gem) rather than rounding -- round explicitly
+          # here first, same as format_duration_from_hours above, so a
+          # fractional-day value doesn't silently lose up to ~1s of precision.
+          Duration.new(seconds: (days * 3600 * 24).round).iso8601
         end
 
         def parse_duration_to_days(duration, property_name, allow_nil: false)

spec/lib/api/v3/utilities/date_time_formatter_spec.rb

@@ -180,8 +180,10 @@
       expect(subject.format_duration_from_hours(5.5)).to eq("PT5H30M")
     end
 
-    it "includes seconds" do
-      expect(subject.format_duration_from_hours(5.501)).to eq("PT5H30M3S")
+    it "includes seconds, rounded rather than truncated" do
+      # 5.501h == 19803.6s -- rounds up to 19804s (PT5H30M4S), not
+      # truncated down to 19803s (PT5H30M3S).
+      expect(subject.format_duration_from_hours(5.501)).to eq("PT5H30M4S")
     end
 
     it "formats ints" do
@@ -230,6 +232,12 @@
       expect(subject.format_duration_from_days(5.501)).to eq("P5DT12H1M26S")
     end
 
+    it "rounds rather than truncates seconds" do
+      # 5.5006 days == 475251.84s -- rounds up to 475252s (P5DT12H52S), not
+      # truncated down to 475251s (P5DT12H51S).
+      expect(subject.format_duration_from_days(5.5006)).to eq("P5DT12H52S")
+    end
+
     it "formats ints" do
       expect(subject.format_duration_from_days(5)).to eq("P5D")
     end