test: complete Jest tests for isProperFraction and ensure all cases pass

Author: Pretty Taruvinga

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

@@ -11,10 +11,21 @@
 // execute the code to ensure all tests pass.
 
 function isProperFraction(numerator, denominator) {
-  if (denominator === 0) return false;
+  if (denominator === 0) {
+    return false; // A fraction with a zero denominator is undefined, so we return false.
+  }
+
+  if (numerator === 0) {
+    return true; // A fraction with a zero numerator is a proper fraction (0/denominator).
+  }
+  if (numerator < 0 && denominator > 0) {
+    return false;
+    // Negative numerator, positive denominator
+  }
   return Math.abs(numerator) < Math.abs(denominator);
+
+  return numerator < denominator && numerator > 0 && denominator > 0;
 }
-//
 // The line below allows us to load the isProperFraction function into tests in other files.
 // This will be useful in the "rewrite tests with jest" step.
 module.exports = isProperFraction;

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

@@ -4,7 +4,31 @@ 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.
 
-// Special case: numerator is zero
+// Special case: denominator is zero
 test(`should return false when denominator is zero`, () => {
   expect(isProperFraction(1, 0)).toEqual(false);
 });
+
+// Case: numerator is zero
+test(`should return true when numerator is zero and denominator is positive`, () => {
+  expect(isProperFraction(0, 1)).toEqual(true);
+});
+test("should return true when numerator is smaller than denominator and both are positive", () => {
+  expect(isProperFraction(1, 2)).toEqual(true);
+});
+
+test("should return false when numerator is equal to denominator", () => {
+  expect(isProperFraction(2, 2)).toEqual(false);
+});
+
+test("should return false when numerator is greater than denominator", () => {
+  expect(isProperFraction(3, 2)).toEqual(false);
+});
+
+test("should return false when numerator is negative", () => {
+  expect(isProperFraction(-1, 2)).toEqual(false);
+});
+
+test("should return true when both numerator and denominator are negative and numerator is smaller than denominator", () => {
+  expect(isProperFraction(-1, -2)).toEqual(true);
+});