Temperature Converter

import * as readline from "node:readline";
import { stdin, stdout } from "node:process";

// cToF converts Celsius to Fahrenheit.
export function cToF(celsius: number): number {
  return (celsius * 9) / 5 + 32;
}

// fToC converts Fahrenheit to Celsius.
export function fToC(fahrenheit: number): number {
  return ((fahrenheit - 32) * 5) / 9;
}

// ask prints a prompt and waits for one line of input. We read lines through
// the readline interface's own async iterator (rl's "for await" protocol)
// instead of its question()/promises API — pulled one at a time with
// it.next(), that iterator is the one part of readline that reliably keeps
// up when several prompts are answered in a row, typed by hand or piped in
// from a file.
function makeAsk(rl: readline.Interface) {
  const it = rl[Symbol.asyncIterator]();
  return async (prompt: string): Promise<string> => {
    stdout.write(prompt);
    const { value, done } = await it.next();
    return done ? "" : value;
  };
}

async function main(): Promise<void> {
  const rl = readline.createInterface({ input: stdin, terminal: false });
  const ask = makeAsk(rl);

  console.log("Temperature Converter");
  console.log("1. Celsius to Fahrenheit");
  console.log("2. Fahrenheit to Celsius");
  const choice = (await ask("Choose 1 or 2: ")).trim();

  if (choice === "1") {
    const celsius = Number((await ask("Enter temperature in Celsius: ")).trim());
    if (Number.isNaN(celsius)) {
      console.log("Please type a number.");
    } else {
      console.log(`${celsius}°C is ${cToF(celsius)}°F`);
    }
  } else if (choice === "2") {
    const fahrenheit = Number((await ask("Enter temperature in Fahrenheit: ")).trim());
    if (Number.isNaN(fahrenheit)) {
      console.log("Please type a number.");
    } else {
      console.log(`${fahrenheit}°F is ${fToC(fahrenheit)}°C`);
    }
  } else {
    console.log("Please choose 1 or 2.");
  }

  rl.close();
}

if (require.main === module) {
  main();
}

import { test } from "node:test";
import assert from "node:assert/strict";
import { cToF, fToC } from "./temperature-converter";

test("freezing point: 0C is 32F", () => {
  assert.equal(cToF(0), 32);
});

test("boiling point: 100C is 212F", () => {
  assert.equal(cToF(100), 212);
});

test("reverse freezing: 32F is 0C", () => {
  assert.equal(fToC(32), 0);
});

test("round trip returns the original number", () => {
  assert.ok(Math.abs(fToC(cToF(25)) - 25) < 0.00001);
});

Temperature Converter
1. Celsius to Fahrenheit
2. Fahrenheit to Celsius
Choose 1 or 2: 1
Enter temperature in Celsius: 100
100°C is 212°F

// Jenkinsfile — runs the type-checker and tests automatically every time the code changes.
pipeline {
    agent any                                  // run on any available machine

    stages {
        stage('Get the code') {
            steps { checkout scm }             // download the latest code
        }
        stage('Set up Node') {
            steps {
                sh 'node --version'                              // confirm Node is installed
                sh 'npm install -D typescript @types/node'       // zero runtime deps — just the compiler and its Node types
            }
        }
        stage('Type-check and test') {
            steps {
                sh 'npx tsc --noEmit'                 // catch type errors before anything runs
                sh 'npx tsc'                           // compile to plain JavaScript
                sh 'node --test converter.test.js'            // Node's built-in test runner, no extra install needed
            }
        }
    }

    post {
        success { echo 'All tests passed.' }
        failure { echo 'A test failed — look above.' }
    }
}