You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

149 lines
3.4 KiB

'use strict';
var chokidar = require('chokidar');
var debounce = require('just-debounce');
var asyncDone = require('async-done');
var defaults = require('object.defaults/immutable');
var isNegatedGlob = require('is-negated-glob');
var anymatch = require('anymatch');
var normalize = require('normalize-path');
var defaultOpts = {
delay: 200,
events: ['add', 'change', 'unlink'],
ignored: [],
ignoreInitial: true,
queue: true,
};
function listenerCount(ee, evtName) {
if (typeof ee.listenerCount === 'function') {
return ee.listenerCount(evtName);
}
return ee.listeners(evtName).length;
}
function hasErrorListener(ee) {
return listenerCount(ee, 'error') !== 0;
}
function exists(val) {
return val != null;
}
function watch(glob, options, cb) {
if (typeof options === 'function') {
cb = options;
options = {};
}
var opt = defaults(options, defaultOpts);
if (!Array.isArray(opt.events)) {
opt.events = [opt.events];
}
if (Array.isArray(glob)) {
// We slice so we don't mutate the passed globs array
glob = glob.slice();
} else {
glob = [glob];
}
var queued = false;
var running = false;
// These use sparse arrays to keep track of the index in the
// original globs array
var positives = new Array(glob.length);
var negatives = new Array(glob.length);
// Reverse the glob here so we don't end up with a positive
// and negative glob in position 0 after a reverse
glob.reverse().forEach(sortGlobs);
function sortGlobs(globString, index) {
var result = isNegatedGlob(globString);
if (result.negated) {
negatives[index] = result.pattern;
} else {
positives[index] = result.pattern;
}
}
var toWatch = positives.filter(exists);
function joinCwd(glob) {
if (glob && opt.cwd) {
return normalize(opt.cwd + '/' + glob);
}
return glob;
}
// We only do add our custom `ignored` if there are some negative globs
// TODO: I'm not sure how to test this
if (negatives.some(exists)) {
var normalizedPositives = positives.map(joinCwd);
var normalizedNegatives = negatives.map(joinCwd);
var shouldBeIgnored = function(path) {
var positiveMatch = anymatch(normalizedPositives, path, true);
var negativeMatch = anymatch(normalizedNegatives, path, true);
// If negativeMatch is -1, that means it was never negated
if (negativeMatch === -1) {
return false;
}
// If the negative is "less than" the positive, that means
// it came later in the glob array before we reversed them
return negativeMatch < positiveMatch;
};
opt.ignored = [].concat(opt.ignored, shouldBeIgnored);
}
var watcher = chokidar.watch(toWatch, opt);
function runComplete(err) {
running = false;
if (err && hasErrorListener(watcher)) {
watcher.emit('error', err);
}
// If we have a run queued, start onChange again
if (queued) {
queued = false;
onChange();
}
}
function onChange() {
if (running) {
if (opt.queue) {
queued = true;
}
return;
}
running = true;
asyncDone(cb, runComplete);
}
var fn;
if (typeof cb === 'function') {
fn = debounce(onChange, opt.delay);
}
function watchEvent(eventName) {
watcher.on(eventName, fn);
}
if (fn) {
opt.events.forEach(watchEvent);
}
return watcher;
}
module.exports = watch;