command.alias.test.js

const commander = require('../');

// Running alias commands is tested in command.executableSubcommand.lookup.test.js
// Test various other behaviours for .alias

test('when command has alias then appears in help', () => {
  const program = new commander.Command();
  program.command('info [thing]').alias('i');
  const helpInformation = program.helpInformation();
  expect(helpInformation).toMatch('info|i');
});

test('when command has aliases added separately then only first appears in help', () => {
  const program = new commander.Command();
  program.command('list [thing]').alias('ls').alias('dir');
  const helpInformation = program.helpInformation();
  expect(helpInformation).toMatch('list|ls ');
});

test('when command has aliases then only first appears in help', () => {
  const program = new commander.Command();
  program.command('list [thing]').aliases(['ls', 'dir']);
  const helpInformation = program.helpInformation();
  expect(helpInformation).toMatch('list|ls ');
});

test('when command name = alias then error', () => {
  const program = new commander.Command();
  expect(() => {
    program.command('fail').alias('fail');
  }).toThrow("Command alias can't be the same as its name");
});

test('when use alias then action handler called', () => {
  const program = new commander.Command();
  const actionMock = jest.fn();
  program.command('list').alias('ls').action(actionMock);
  program.parse(['ls'], { from: 'user' });
  expect(actionMock).toHaveBeenCalled();
});

test('when use second alias added separately then action handler called', () => {
  const program = new commander.Command();
  const actionMock = jest.fn();
  program.command('list').alias('ls').alias('dir').action(actionMock);
  program.parse(['dir'], { from: 'user' });
  expect(actionMock).toHaveBeenCalled();
});

test('when use second of aliases then action handler called', () => {
  const program = new commander.Command();
  const actionMock = jest.fn();
  program.command('list').aliases(['ls', 'dir']).action(actionMock);
  program.parse(['dir'], { from: 'user' });
  expect(actionMock).toHaveBeenCalled();
});

test('when set alias then can get alias', () => {
  const program = new commander.Command();
  const alias = 'abcde';
  program.alias(alias);
  expect(program.alias()).toEqual(alias);
});

test('when set aliases then can get aliases', () => {
  const program = new commander.Command();
  const aliases = ['a', 'b'];
  program.aliases(aliases);
  expect(program.aliases()).toEqual(aliases);
});

test('when set alias on executable then can get alias', () => {
  const program = new commander.Command();
  const alias = 'abcde';
  program.command('external', 'external command').alias(alias);
  expect(program.commands[0].alias()).toEqual(alias);
});

describe('aliases parameter is treated as readonly, per TypeScript declaration', () => {
  test('when aliases called then parameter does not change', () => {
    // Unlikely this could break, but check the API we are declaring in TypeScript.
    const original = ['b', 'bld'];
    const param = original.slice();
    new commander.Command('build').aliases(param);
    expect(param).toEqual(original);
  });

  test('when aliases called and aliases later changed then parameter does not change', () => {
    const original = ['b', 'bld'];
    const param = original.slice();
    const cmd = new commander.Command('build').aliases(param);
    cmd.alias('BBB');
    expect(param).toEqual(original);
  });

  test('when aliases called and parameter later changed then aliases does not change', () => {
    const original = ['b', 'bld'];
    const param = original.slice();
    const cmd = new commander.Command('build').aliases(param);
    param.length = 0;
    expect(cmd.aliases()).toEqual(original);
  });
});