index.test.js

const { getColumnNumber } = require("./index");

test("A", () => {
  expect(getColumnNumber("A")).toBe(0);
});

test("B", () => {
  expect(getColumnNumber("B")).toBe(1);
});

test("Z", () => {
  expect(getColumnNumber("Z")).toBe(25);
});

test("AA", () => {
  expect(getColumnNumber("AA")).toBe(26);
});

test("AZ", () => {
  expect(getColumnNumber("AZ")).toBe(51);
});

test("ZA", () => {
  expect(getColumnNumber("ZA")).toBe(676);
});

test("ZZ", () => {
  expect(getColumnNumber("ZZ")).toBe(701);
});

test("APN", () => {
  expect(getColumnNumber("APN")).toBe(1105);
});

test("AAAA", () => {
  expect(getColumnNumber("AAAA")).toBe(18278);
});

test("AZCA", () => {
  expect(getColumnNumber("AZCA")).toBe(35230);
});