R62 A1-A6：2026年中国法定假期日历

server/tests/unit/services/leave.test.js

@@ -1,6 +1,7 @@
 const {
   calculateRequestedDays,
   calculateRequestedDaysByWorkingCalendar,
+  calculateRequestedDaysPreviewByWorkingCalendar,
   leaveRangesOverlap,
   summarizeLeaveLedgerEntries,
 } = require("../../../src/services/leave");
@@ -98,6 +99,54 @@ describe("Leave Service", () => {
     });
   });
 
+  describe("calculateRequestedDaysPreviewByWorkingCalendar", () => {
+    it("returns official holiday counts while excluding holidays from requested days", () => {
+      expect(
+        calculateRequestedDaysPreviewByWorkingCalendar({
+          startDate: "2026-01-01",
+          endDate: "2026-01-04",
+          startSession: "am",
+          endSession: "pm",
+          calendarDays: [
+            { date: "2026-01-01", day_type: "holiday" },
+            { date: "2026-01-02", day_type: "holiday" },
+            { date: "2026-01-03", day_type: "holiday" },
+            { date: "2026-01-04", day_type: "adjusted_workday" },
+          ],
+        }),
+      ).toEqual({
+        requestedDays: 1,
+        naturalRequestedDays: 4,
+        holidayDayCount: 3,
+        weekendDayCount: 0,
+        adjustedWorkdayCount: 1,
+        calendarApplied: true,
+      });
+    });
+
+    it("keeps half-day precision for adjusted workdays in preview payload", () => {
+      expect(
+        calculateRequestedDaysPreviewByWorkingCalendar({
+          startDate: "2026-01-03",
+          endDate: "2026-01-04",
+          startSession: "pm",
+          endSession: "am",
+          calendarDays: [
+            { date: "2026-01-03", day_type: "holiday" },
+            { date: "2026-01-04", day_type: "adjusted_workday" },
+          ],
+        }),
+      ).toEqual({
+        requestedDays: 0.5,
+        naturalRequestedDays: 1,
+        holidayDayCount: 0.5,
+        weekendDayCount: 0,
+        adjustedWorkdayCount: 0.5,
+        calendarApplied: true,
+      });
+    });
+  });
+
   describe("leaveRangesOverlap", () => {
     it("detects overlapping half-day ranges", () => {
       expect(