R62 Fix A1-A6：请假预览全非工作日处理

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

@@ -121,6 +121,7 @@ describe("Leave Service", () => {
         weekendDayCount: 0,
         adjustedWorkdayCount: 1,
         calendarApplied: true,
+        isNonWorkingRange: false,
       });
     });
 
@@ -143,6 +144,34 @@ describe("Leave Service", () => {
         weekendDayCount: 0,
         adjustedWorkdayCount: 0.5,
         calendarApplied: true,
+        isNonWorkingRange: false,
+      });
+    });
+
+    it("returns zero-day preview for fully non-working ranges when explicitly allowed", () => {
+      expect(
+        calculateRequestedDaysPreviewByWorkingCalendar({
+          startDate: "2026-05-01",
+          endDate: "2026-05-05",
+          startSession: "am",
+          endSession: "pm",
+          allowNonWorkingRange: true,
+          calendarDays: [
+            { date: "2026-05-01", day_type: "holiday" },
+            { date: "2026-05-02", day_type: "holiday" },
+            { date: "2026-05-03", day_type: "holiday" },
+            { date: "2026-05-04", day_type: "holiday" },
+            { date: "2026-05-05", day_type: "holiday" },
+          ],
+        }),
+      ).toEqual({
+        requestedDays: 0,
+        naturalRequestedDays: 5,
+        holidayDayCount: 5,
+        weekendDayCount: 0,
+        adjustedWorkdayCount: 0,
+        calendarApplied: true,
+        isNonWorkingRange: true,
       });
     });
   });