blob: 6a5e3fc94c3ab80e123c3056b6c5dbe056d21658 [file] [log] [blame]
/**
* This is the common logic for both the Node.js and web browser
* implementations of `debug()`.
*
* Expose `debug()` as the module.
*/
exports = module.exports = createDebug.debug = createDebug['default'] = createDebug;
exports.coerce = coerce;
exports.disable = disable;
exports.enable = enable;
exports.enabled = enabled;
exports.humanize = require('ms');
/**
* The currently active debug mode names, and names to skip.
*/
exports.names = [];
exports.skips = [];
/**
* Map of special "%n" handling functions, for the debug "format" argument.
*
* Valid key names are a single, lower or upper-case letter, i.e. "n" and "N".
*/
exports.formatters = {};
/**
* Previous log timestamp.
*/
var prevTime;
/**
* Select a color.
* @param {String} namespace
* @return {Number}
* @api private
*/
function selectColor(namespace) {
var hash = 0, i;
for (i in namespace) {
hash = ((hash << 5) - hash) + namespace.charCodeAt(i);
hash |= 0; // Convert to 32bit integer
}
return exports.colors[Math.abs(hash) % exports.colors.length];
}
/**
* Create a debugger with the given `namespace`.
*
* @param {String} namespace
* @return {Function}
* @api public
*/
function createDebug(namespace) {
function debug() {
// disabled?
if (!debug.enabled) return;
var self = debug;
// set `diff` timestamp
var curr = +new Date();
var ms = curr - (prevTime || curr);
self.diff = ms;
self.prev = prevTime;
self.curr = curr;
prevTime = curr;
// turn the `arguments` into a proper Array
var args = new Array(arguments.length);
for (var i = 0; i < args.length; i++) {
args[i] = arguments[i];
}
args[0] = exports.coerce(args[0]);
if ('string' !== typeof args[0]) {
// anything else let's inspect with %O
args.unshift('%O');
}
// apply any `formatters` transformations
var index = 0;
args[0] = args[0].replace(/%([a-zA-Z%])/g, function(match, format) {
// if we encounter an escaped % then don't increase the array index
if (match === '%%') return match;
index++;
var formatter = exports.formatters[format];
if ('function' === typeof formatter) {
var val = args[index];
match = formatter.call(self, val);
// now we need to remove `args[index]` since it's inlined in the `format`
args.splice(index, 1);
index--;
}
return match;
});
// apply env-specific formatting (colors, etc.)
exports.formatArgs.call(self, args);
var logFn = debug.log || exports.log || console.log.bind(console);
logFn.apply(self, args);
}
debug.namespace = namespace;
debug.enabled = exports.enabled(namespace);
debug.useColors = exports.useColors();
debug.color = selectColor(namespace);
// env-specific initialization logic for debug instances
if ('function' === typeof exports.init) {
exports.init(debug);
}
return debug;
}
/**
* Enables a debug mode by namespaces. This can include modes
* separated by a colon and wildcards.
*
* @param {String} namespaces
* @api public
*/
function enable(namespaces) {
exports.save(namespaces);
exports.names = [];
exports.skips = [];
var split = (typeof namespaces === 'string' ? namespaces : '').split(/[\s,]+/);
var len = split.length;
for (var i = 0; i < len; i++) {
if (!split[i]) continue; // ignore empty strings
namespaces = split[i].replace(/\*/g, '.*?');
if (namespaces[0] === '-') {
exports.skips.push(new RegExp('^' + namespaces.substr(1) + '$'));
} else {
exports.names.push(new RegExp('^' + namespaces + '$'));
}
}
}
/**
* Disable debug output.
*
* @api public
*/
function disable() {
exports.enable('');
}
/**
* Returns true if the given mode name is enabled, false otherwise.
*
* @param {String} name
* @return {Boolean}
* @api public
*/
function enabled(name) {
var i, len;
for (i = 0, len = exports.skips.length; i < len; i++) {
if (exports.skips[i].test(name)) {
return false;
}
}
for (i = 0, len = exports.names.length; i < len; i++) {
if (exports.names[i].test(name)) {
return true;
}
}
return false;
}
/**
* Coerce `val`.
*
* @param {Mixed} val
* @return {Mixed}
* @api private
*/
function coerce(val) {
if (val instanceof Error) return val.stack || val.message;
return val;
}