From 336758c9e9aa6f1a5457aa0b223af064d882dc1c Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Sun, 9 Aug 2026 09:57:32 +0000
Subject: [PATCH] test: add edge case tests for isCalendarUnit

Co-authored-by: Horizontal42 <75383519+Horizontal42@users.noreply.github.com>
---
 src/engine/datetime.test.ts | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/src/engine/datetime.test.ts b/src/engine/datetime.test.ts
index c327c52..aa636c9 100644
--- a/src/engine/datetime.test.ts
+++ b/src/engine/datetime.test.ts
@@ -204,5 +204,32 @@ describe("datetime", () => {
       expect(isCalendarUnit("minute", 1)).toBe(false);
       expect(isCalendarUnit("unit:meter", 1)).toBe(false);
     });
+
+    it("should handle edge cases for amount", () => {
+      expect(isCalendarUnit("day", 0)).toBe(true);
+      expect(isCalendarUnit("day", Number.MAX_SAFE_INTEGER)).toBe(true);
+      expect(isCalendarUnit("day", Number.MIN_SAFE_INTEGER)).toBe(true);
+
+      expect(isCalendarUnit("day", NaN)).toBe(false);
+      expect(isCalendarUnit("day", Infinity)).toBe(false);
+      expect(isCalendarUnit("day", -Infinity)).toBe(false);
+    });
+
+    it("should handle edge cases for unitId string format", () => {
+      expect(isCalendarUnit("", 1)).toBe(false);
+      expect(isCalendarUnit(":", 1)).toBe(false);
+
+      // string.split(":") behavior:
+      expect(isCalendarUnit("time:month", 1)).toBe(true);
+      expect(isCalendarUnit(":day", 1)).toBe(true);
+      expect(isCalendarUnit("day:", 1)).toBe(false);
+      expect(isCalendarUnit("a:day:c", 1)).toBe(true);
+    });
+
+    it("should return false for case-sensitive mismatch", () => {
+      expect(isCalendarUnit("Day", 1)).toBe(false);
+      expect(isCalendarUnit("YEAR", 1)).toBe(false);
+      expect(isCalendarUnit("MONTH", 1)).toBe(false);
+    });
   });
 });