blob: 3b0a9183d5a9aea736dd7717d074b5f1271ddaa9 [file] [log] [blame]
/**
* Module dependencies.
*/
var tty = require('tty');
/**
* Expose `debug()` as the module.
*/
module.exports = debug;
/**
* Enabled debuggers.
*/
var names = []
, skips = [];
(process.env.DEBUG || '')
.split(/[\s,]+/)
.forEach(function(name){
name = name.replace('*', '.*?');
if (name[0] === '-') {
skips.push(new RegExp('^' + name.substr(1) + '$'));
} else {
names.push(new RegExp('^' + name + '$'));
}
});
/**
* Colors.
*/
var colors = [6, 2, 3, 4, 5, 1];
/**
* Previous debug() call.
*/
var prev = {};
/**
* Previously assigned color.
*/
var prevColor = 0;
/**
* Is stdout a TTY? Colored output is disabled when `true`.
*/
var isatty = tty.isatty(2);
/**
* Select a color.
*
* @return {Number}
* @api private
*/
function color() {
return colors[prevColor++ % colors.length];
}
/**
* Humanize the given `ms`.
*
* @param {Number} m
* @return {String}
* @api private
*/
function humanize(ms) {
var sec = 1000
, min = 60 * 1000
, hour = 60 * min;
if (ms >= hour) return (ms / hour).toFixed(1) + 'h';
if (ms >= min) return (ms / min).toFixed(1) + 'm';
if (ms >= sec) return (ms / sec | 0) + 's';
return ms + 'ms';
}
/**
* Create a debugger with the given `name`.
*
* @param {String} name
* @return {Type}
* @api public
*/
function debug(name) {
function disabled(){}
disabled.enabled = false;
var match = skips.some(function(re){
return re.test(name);
});
if (match) return disabled;
match = names.some(function(re){
return re.test(name);
});
if (!match) return disabled;
var c = color();
function colored(fmt) {
fmt = coerce(fmt);
var curr = new Date;
var ms = curr - (prev[name] || curr);
prev[name] = curr;
fmt = ' \u001b[9' + c + 'm' + name + ' '
+ '\u001b[3' + c + 'm\u001b[90m'
+ fmt + '\u001b[3' + c + 'm'
+ ' +' + humanize(ms) + '\u001b[0m';
console.error.apply(this, arguments);
}
function plain(fmt) {
fmt = coerce(fmt);
fmt = new Date().toUTCString()
+ ' ' + name + ' ' + fmt;
console.error.apply(this, arguments);
}
colored.enabled = plain.enabled = true;
return isatty || process.env.DEBUG_COLORS
? colored
: plain;
}
/**
* Coerce `val`.
*/
function coerce(val) {
if (val instanceof Error) return val.stack || val.message;
return val;
}