meteor/packages/meteor/debug.js

var suppress = 0;

// replacement for console.log. This is a temporary API. We should
// provide a real logging API soon (possibly just a polyfill for
// console?)
//
// NOTE: this is used on the server to print the warning about
// having autopublish enabled when you probably meant to turn it
// off. it's not really the proper use of something called
// _debug. the intent is for this message to go to the terminal and
// be very visible. if you change _debug to go someplace else, etc,
// please fix the autopublish code to do something reasonable.
//
Meteor._debug = function (/* arguments */) {
  if (suppress) {
    suppress--;
    return;
  }
  if (typeof console !== 'undefined' &&
      typeof console.log !== 'undefined') {
    if (arguments.length == 0) { // IE Companion breaks otherwise
      // IE10 PP4 requires at least one argument
      console.log('');
    } else {
      // IE doesn't have console.log.apply, it's not a real Object.
      // http://stackoverflow.com/questions/5538972/console-log-apply-not-working-in-ie9
      // http://patik.com/blog/complete-cross-browser-console-log/
      if (typeof console.log.apply === "function") {
        // Most browsers

        // Chrome and Safari only hyperlink URLs to source files in first argument of
        // console.log, so try to call it with one argument if possible.
        // Approach taken here: If all arguments are strings, join them on space.
        // See https://github.com/meteor/meteor/pull/732#issuecomment-13975991
        var allArgumentsOfTypeString = true;
        for (var i = 0; i < arguments.length; i++)
          if (typeof arguments[i] !== "string")
            allArgumentsOfTypeString = false;

        if (allArgumentsOfTypeString)
          console.log.apply(console, [Array.prototype.join.call(arguments, " ")]);
        else
          console.log.apply(console, arguments);

      } else if (typeof Function.prototype.bind === "function") {
        // IE9
        var log = Function.prototype.bind.call(console.log, console);
        log.apply(console, arguments);
      }
    }
  }
};

// Suppress the next 'count' Meteor._debug messsages. Use this to
// stop tests from spamming the console.
//
Meteor._suppress_log = function (count) {
  suppress += count;
};

Meteor._suppressed_log_expected = function () {
  return suppress !== 0;
};