test: add comprehensive Jest tests for isProperFraction function

Author: Tarawally

Sprint-3/1-implement-and-rewrite-tests/rewrite-tests-with-jest/2-is-proper-fraction.test.js

@@ -6,8 +6,20 @@ test("should return true for a proper fraction", () => {
   expect(isProperFraction(2, 3)).toEqual(true);
 });
 
-// Case 2: Identify Improper Fractions:
+test("should return false for an improper fraction (numerator >= denominator)", () => {
+  expect(isProperFraction(5, 2)).toEqual(false);
+  expect(isProperFraction(10, 3)).toEqual(false);
+  expect(isProperFraction(7, 7)).toEqual(false);
+});
 
-// Case 3: Identify Negative Fractions:
+test("should return true for a negative proper fraction (|numerator| < denominator)", () => {
+  expect(isProperFraction(-4, 7)).toEqual(true);
+  expect(isProperFraction(-2, 5)).toEqual(true);
+  expect(isProperFraction(-1, 10)).toEqual(true);
+});
 
-// Case 4: Identify Equal Numerator and Denominator:
+test("should return false when numerator equals denominator", () => {
+  expect(isProperFraction(3, 3)).toEqual(false);
+  expect(isProperFraction(1, 1)).toEqual(false);
+  expect(isProperFraction(100, 100)).toEqual(false);
+});