Test Driven Development

fraction_test.ts

@@ -34,3 +34,39 @@ Deno.test("1/3 + 2/6 = 2/3 is roughly 0.67", () => {
   // Assert
   assertAlmostEquals(left.toFloat(0.01), 0.67);
 });
+
+Deno.test("3/3 - 1/3 = 2/3 is roughly 0.67", () => {
+  // Arrange
+  const left = new Fraction(3, 3);
+  const right = new Fraction(1, 3);
+
+  // Act
+  left.subtract(right);
+
+  // Assert
+  assertAlmostEquals(left.toFloat(0.01), 0.67);
+});
+
+Deno.test("2/3 * 2/3 = 4/9 is roughly 0.444", () => {
+  // Arrange
+  const left = new Fraction(2, 3);
+  const right = new Fraction(2, 3);
+
+  // Act
+  left.multiply(right);
+
+  // Assert
+  assertAlmostEquals(left.toFloat(0.001), 0.444);
+});
+
+Deno.test("10/3 / 2/3 = 5/3 is roughly 2.0", () => {
+  // Arrange
+  const left = new Fraction(10, 3);
+  const right = new Fraction(5, 3);
+
+  // Act
+  left.divide(right);
+
+  // Assert
+  assertAlmostEquals(left.toFloat(0.1), 2.0);
+});

gcd.ts

@@ -0,0 +1,8 @@
+export function gcdBruteForce(a: number, b: number): number {
+  for (let i = Math.min(a, b); i >= 1; i--) {
+    if (a % i === 0 && b % i === 0) {
+      return i;
+    }
+  }
+  return 1;
+}

gcd_test.ts

@@ -0,0 +1,6 @@
+// gcd.test.ts
+import { assertEquals } from "jsr:@std/assert";
+import { gcdBruteForce } from "./gcd.ts";
+
+Deno.test("ggT(1, 1) = 1", () => assertEquals(gcdBruteForce(1, 1), 1));
+Deno.test("ggT(12, 8) = 4", () => assertEquals(gcdBruteForce(12, 8), 4));

geometry.ts

@@ -42,7 +42,8 @@ export class Rectangle implements Shape {
   ) {}
 
   circumference(): number {
-    return 2 * (this.width() + 2 * this.height());
+    // return 2 * (this.width() + 2 * this.height()); // this is a bug and does NOT work correctly
+    return 2 * (this.width() + this.height()); // this would be the corrected version
   }
 
   area(): number {

geometry_test.ts

@@ -1,5 +1,6 @@
 import { assertAlmostEquals } from "@std/assert";
 import { Circle, Point2D } from "./geometry.ts";
+import { Rectangle } from "./geometry.ts";
 
 Deno.test("circumference of a circle with radius 5 is roughtly 31.416", () => {
   // Given
@@ -11,3 +12,59 @@ Deno.test("circumference of a circle with radius 5 is roughtly 31.416", () => {
   // Then
   assertAlmostEquals(actual, 31.416, 0.01);
 });
+
+Deno.test("area of a circle with radius 5 is roughtly 78.54", () => {
+  // Given
+  const circle = new Circle(new Point2D(3, 4), 5);
+
+  // When
+  const actual = circle.area();
+
+  // Then
+  assertAlmostEquals(actual, 78.54, 0.01);
+});
+
+Deno.test("diameter of a circle with radius 5 is roughtly 10", () => {
+  // Given
+  const circle = new Circle(new Point2D(3, 4), 5);
+
+  // When
+  const actual = circle.diameter();
+
+
+  // Then
+  assertAlmostEquals(actual, 10, 0.01);
+});
+
+Deno.test("circumference of a rectangle with width 5 and height 3 is roughtly 16", () => {
+  // Given
+  const rect = new Rectangle(new Point2D(0, 0), new Point2D(5, 3));
+
+  // When
+  const actual = rect.circumference();
+
+  // Then
+  assertAlmostEquals(actual, 16, 0.01);
+});
+
+Deno.test("area of a rectangle with width 5 and height 3 is roughtly 15", () => {
+  // Given
+  const rect = new Rectangle(new Point2D(0, 0), new Point2D(5, 3));
+
+  // When
+  const actual = rect.area();
+
+  // Then
+  assertAlmostEquals(actual, 15, 0.01);
+});
+
+Deno.test("diagonal of a rectangle with width 5 and height 3 is roughtly 5.83", () => {
+  // Given
+  const rect = new Rectangle(new Point2D(0, 0), new Point2D(5, 3));
+
+  // When
+  const actual = rect.diagonal();
+
+  // Then
+  assertAlmostEquals(actual, 5.83, 0.01);
+});