Pest

An implementation of a testing framework for Typescript applications.

Testing

To test this implementation, you can clone the repository and run...

npm test

Running the above in the root directory will execute the tests in the test directory.

Contributing

You can contribute by either trying out the package, implementing a fix, or adding a new feature.

Read the contribution guide for more information

Usage

Test a function with an object response

function parsePathVariables(
  path: string,
  route: string
): Record<string, string> {
  let pathVariables = path.split('/');
  let routeVariables = route.split('/');
  let pathVariablesObject: Record<string, string> = {};
  if (routeVariables.length === pathVariables.length) {
    for (let i = 0; i < routeVariables.length; i++) {
      if (routeVariables[i].startsWith(':')) {
        pathVariablesObject[routeVariables[i].slice(1)] = pathVariables[i];
      }
    }
  }
  return pathVariablesObject;
}

pest('Should parse path variables', async () => {
  const path = '/test/1234567890';
  const route = '/test/:id';
  const params = parsePathVariables(path, route);
  expect(params).toBeObject({
    id: '1234567890',
  });
});

Test a function with before and after hooks

import * as fs from 'fs';

function loadEnv(path?: string) {
  const env = fs.readFileSync(path || '.env', 'utf8');
  const lines = env.split('\n');
  lines.forEach((line) => {
    if (!line.startsWith('#') && line.trim() !== '') {
      const [key, value] = line.split('=');
      process.env[key.trim()] = value.trim();
    }
  });
}

beforePest(() => {
  // create a .env file and write some data
  fs.writeFileSync(
    '.env.test',
    'PORT=3000\nDUMMY_KEY=1234567890\nDUMMY_KEY_2=0987654321'
  );
});

pest('Should load env into process', async () => {
  // load the .env file
  loadEnv('.env.test');

  // check if the process.env object has the correct data
  expect(process.env.PORT).toBe('3000');
  expect(process.env.DUMMY_KEY).toBe('1234567890');
  expect(process.env.DUMMY_KEY_2).toBe('0987654321');
});

afterPest(() => {
  // delete the .env file
  fs.unlinkSync('.env.test');
});

Test the occurrence of an element in an array

function removeFirstOccurence(list: string[], item: string) {
  let index = list.indexOf(item);
  if (index > -1) {
    list.splice(index, 1);
  }
  return list;
}

pest('Should remove first occurence from a list', async () => {
  const list = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'd'];
  const item = 'd';
  const newList = removeFirstOccurence(list, item);
  expect(item).toOccur(1).in(newList);
});

Test a function that returns a promise

import * as http from 'http';

function makeRequest(options: { url: string }) {
  return new Promise((resolve, reject) => {
    http.get(options.url, (res) => {
      let data = '';
      res.on('data', (chunk) => {
        data += chunk;
      });
      res.on('end', () => {
        resolve(data);
      });
    });
  });
}

pest('Should make an api call', async () => {
  const data = await makeRequest({
    url: 'http://abbrefy.xyz/api/v1/me/links/',
  });
  expect(JSON.parse(data as string)).toBeObject(
    JSON.parse(`{"error":"Please provide your API key.","status":false}`)
  );
});