is propper function jest

Author: ihortar

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

@@ -3,8 +3,45 @@
 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.
+describe("isProperFraction", () => {
+  // Denominator zero case
+  test("should return false when denominator is zero", () => {
+    expect(isProperFraction(1, 0)).toBe(false);
+  });
 
-// Special case: numerator is zero
-test(`should return false when denominator is zero`, () => {
-  expect(isProperFraction(1, 0)).toEqual(false);
-});
+  // Denominator negative case
+  test("should return false when denominator is negative", () => {
+    expect(isProperFraction(1, -5)).toBe(false);
+    expect(isProperFraction(-3, -4)).toBe(false);
+  });
+
+  // Proper positive fraction (numerator < denominator)
+  test("should return true for positive proper fractions", () => {
+    expect(isProperFraction(1, 2)).toBe(true);
+    expect(isProperFraction(3, 4)).toBe(true);
+  });
+
+  // Improper positive fraction (numerator >= denominator)
+  test("should return false for improper positive fractions", () => {
+    expect(isProperFraction(4, 3)).toBe(false);
+    expect(isProperFraction(5, 5)).toBe(false);
+  });
+
+  // Negative numerators (proper fraction)
+  test("should return true for negative proper fractions", () => {
+    expect(isProperFraction(-1, 3)).toBe(true);
+  });
+
+  // Negative numerators that make fraction improper
+  test("should return false for negative improper fractions", () => {
+    expect(isProperFraction(-5, 5)).toBe(false);
+  });
+
+  // Mixed sign case (denominator positive, numerator positive/negative)
+  test("should handle mixed signs correctly", () => {
+    expect(isProperFraction(2, 3)).toBe(true);
+    expect(isProperFraction(-2, 3)).toBe(true);
+    expect(isProperFraction(4, 3)).toBe(false);
+    expect(isProperFraction(-4, 3)).toBe(false);
+  });
+});