tcl-js/test/testConsole.js

tcl-js is a tcl intepreter written completely in Typescript. It is meant to replicate the tcl-sh interpreter as closely as possible.

// Copyright (c) 2014-2015 Titanium I.T. LLC. All rights reserved. For license, see "README" or "LICENSE" file.
'use strict';

exports.stdout = new TestStream(process.stdout);
exports.stderr = new TestStream(process.stderr);

function TestStream(stream) {
  this._stream = stream;
}

TestStream.prototype.inspect = function(options) {
  expectNoFunction(arguments, 'inspect', 'inspectSync');

  var isTTY;
  if (options && options.isTTY !== undefined) {
    isTTY = options.isTTY;
  }

  // This code inspired by http://userinexperience.com/?p=714
  var output = [];
  var stream = this._stream;

  var originalWrite = stream.write;
  stream.write = function(string) {
    output.push(string);
  };

  var originalIsTTY = stream.isTTY;
  if (isTTY !== undefined) {
    stream.isTTY = isTTY;
  }

  return {
    output: output,
    restore: function() {
      stream.write = originalWrite;
      stream.isTTY = originalIsTTY;
    },
  };
};

TestStream.prototype.inspectSync = async function(options, fn) {
  expectFunction(arguments, 'inspectSync', 'inspect');

  if (arguments.length === 1) {
    fn = options;
    options = {};
  }

  var inspect = this.inspect(options);
  try {
    await fn(inspect.output);
  } finally {
    inspect.restore();
  }
  return inspect.output;
};

TestStream.prototype.ignore = function(options) {
  expectNoFunction(arguments, 'ignore', 'ignoreSync');

  return this.inspect(options).restore;
};

TestStream.prototype.ignoreSync = async function(options, fn) {
  expectFunction(arguments, 'ignoreSync', 'ignore');

  if (arguments.length === 1) {
    fn = options;
    options = {};
  }

  await this.inspectSync(options, fn);
};

function expectNoFunction(args, calledFunction, functionToCallInstead) {
  if ((args.length && typeof args[0] === 'function') || args.length > 1) {
    throw new Error(
      calledFunction +
        "() doesn't take a function parameter. Did you mean to call " +
        functionToCallInstead +
        '()?',
    );
  }
}

function expectFunction(args, calledFunction, functionToCallInstead) {
  if (
    args.length === 0 ||
    args.length > 2 ||
    typeof args[args.length - 1] !== 'function'
  ) {
    throw new Error(
      calledFunction +
        '() requires a function parameter. Did you mean to call ' +
        functionToCallInstead +
        '()?',
    );
  }
}