BinarySearch.test.ts

import { binarySearchIterative, binarySearchRecursive } from "../BinarySearch";

describe("BinarySearch", () => {
    const testArray: number[] = [1,2,3,4];
    type FunctionsArray = { (array: number[], index: number): number }[];
    const functions: FunctionsArray = [binarySearchIterative, binarySearchRecursive];

    for (const func of functions) {
        it("should be defined", () => {
            expect(func(testArray, 2)).toBeDefined();
        });
        it("should return a number", () => {
            expect(typeof func(testArray, 2)).toBe("number");
        });
        it("should return -1 if the target is not found in the array", () => {
            expect(func(testArray, 5)).toBe(-1);
        });
        it("should return -1 if there are no elements in the array", () => {
            expect(func([], 5)).toBe(-1);
        });
        it("should return the index of the target if it is found in the array", () => {
            expect(func(testArray, 2)).toBe(1);
        });
        it("should return a correct index of target when the array contains duplicate values", () => {
            expect(func([1,2,2,3,3,3,4], 2)).toBe(1);
        });
        it("should return the first index when the target is the first item in the array", () => {
            expect(func(testArray, 1)).toBe(0);
        });
        it("should return the last index when the target is the last item in the array", () => {
            expect(func(testArray, 4)).toBe(3);
        });
    }
});