Add comprehensive Jest tests for isProperFraction function covering various cases

Author: Monsur0001

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

@@ -2,9 +2,63 @@
 // We will use the same function, but write tests for it using Jest in this file.
 const isProperFraction = require("../implement/2-is-proper-fraction");
 
+
 // TODO: Write tests in Jest syntax to cover all combinations of positives, negatives, zeros, and other categories.
+const isProperFraction = require("../implement/2-is-proper-fraction");
+
+// Case 1: Proper fractions
+test(`should return true for proper fractions`, () => {
+  expect(isProperFraction(1, 2)).toEqual(true);
+  expect(isProperFraction(-1, 2)).toEqual(true);
+  expect(isProperFraction(-1, -2)).toEqual(true);
+});
+
+// Case 2: Improper fractions
+test(`should return false for improper fractions`, () => {
+  expect(isProperFraction(2, 1)).toEqual(false);
+  expect(isProperFraction(3, 2)).toEqual(false);
+  expect(isProperFraction(-3, 2)).toEqual(false);
+  expect(isProperFraction(3, -2)).toEqual(false);
+});
+
+// Case 3: Zero numerator
+test(`should return true when numerator is zero`, () => {
+  expect(isProperFraction(0, 1)).toEqual(true);
+  expect(isProperFraction(0, -1)).toEqual(true);
+});
+
+// Case 4: Zero denominator
+test(`should return false when denominator is zero`, () => {
+  expect(isProperFraction(1, 0)).toEqual(false);
+  expect(isProperFraction(-1, 0)).toEqual(false);
+  expect(isProperFraction(0, 0)).toEqual(false);
+});
+
+// Case 5: Negative fractions
+test(`should return false for negative fractions with positive denominator`, () => {
+  expect(isProperFraction(-1, 2)).toEqual(true);
+});
+
+test(`should return false for negative fractions with negative denominator`, () => {
+  expect(isProperFraction(-1, -2)).toEqual(true);
+});
+
+// Case 6: Invalid fractions (denominator is zero)
+test(`should return false when denominator is zero`, () => {
+  expect(isProperFraction(1, 0)).toEqual(false);
+  expect(isProperFraction(-1, 0)).toEqual(false);
+  expect(isProperFraction(0, 0)).toEqual(false);
+});
+
+// Case 7: Special case: numerator is zero
+test(`should return true when numerator is zero`, () => {
+  expect(isProperFraction(0, 1)).toEqual(true);
+  expect(isProperFraction(0, -1)).toEqual(true);
+}); 
+
 
 // Special case: numerator is zero
 test(`should return false when denominator is zero`, () => {
   expect(isProperFraction(1, 0)).toEqual(false);
 });
+