lepu-test-platform-web/node_modules/gaze/lib/gaze.js

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/*
* gaze
* https://github.com/shama/gaze
*
* Copyright (c) 2018 Kyle Robinson Young
* Licensed under the MIT license.
*/
'use strict';
// libs
var util = require('util');
var EE = require('events').EventEmitter;
var fs = require('fs');
var path = require('path');
var globule = require('globule');
var helper = require('./helper');
// shim setImmediate for node v0.8
var setImmediate = require('timers').setImmediate;
if (typeof setImmediate !== 'function') {
setImmediate = process.nextTick;
}
// globals
var delay = 10;
// `Gaze` EventEmitter object to return in the callback
function Gaze (patterns, opts, done) {
var self = this;
EE.call(self);
// If second arg is the callback
if (typeof opts === 'function') {
done = opts;
opts = {};
}
// Default options
opts = opts || {};
opts.mark = true;
opts.interval = opts.interval || 100;
opts.debounceDelay = opts.debounceDelay || 500;
opts.cwd = opts.cwd || process.cwd();
this.options = opts;
// Default done callback
done = done || function () {};
// Remember our watched dir:files
this._watched = Object.create(null);
// Store watchers
this._watchers = Object.create(null);
// Store watchFile listeners
this._pollers = Object.create(null);
// Store patterns
this._patterns = [];
// Cached events for debouncing
this._cached = Object.create(null);
// Set maxListeners
if (this.options.maxListeners != null) {
this.setMaxListeners(this.options.maxListeners);
Gaze.super_.prototype.setMaxListeners(this.options.maxListeners);
delete this.options.maxListeners;
}
// Initialize the watch on files
if (patterns) {
this.add(patterns, done);
}
// keep the process alive
this._keepalive = setInterval(function () {}, 200);
return this;
}
util.inherits(Gaze, EE);
// Main entry point. Start watching and call done when setup
module.exports = function gaze (patterns, opts, done) {
return new Gaze(patterns, opts, done);
};
module.exports.Gaze = Gaze;
// Override the emit function to emit `all` events
// and debounce on duplicate events per file
Gaze.prototype.emit = function () {
var self = this;
var args = arguments;
var e = args[0];
var filepath = args[1];
var timeoutId;
// If not added/deleted/changed/renamed then just emit the event
if (e.slice(-2) !== 'ed') {
Gaze.super_.prototype.emit.apply(self, args);
return this;
}
// Detect rename event, if added and previous deleted is in the cache
if (e === 'added') {
Object.keys(this._cached).forEach(function (oldFile) {
if (self._cached[oldFile].indexOf('deleted') !== -1) {
args[0] = e = 'renamed';
[].push.call(args, oldFile);
delete self._cached[oldFile];
return false;
}
});
}
// If cached doesnt exist, create a delay before running the next
// then emit the event
var cache = this._cached[filepath] || [];
if (cache.indexOf(e) === -1) {
helper.objectPush(self._cached, filepath, e);
clearTimeout(timeoutId);
timeoutId = setTimeout(function () {
delete self._cached[filepath];
}, this.options.debounceDelay);
// Emit the event and `all` event
Gaze.super_.prototype.emit.apply(self, args);
Gaze.super_.prototype.emit.apply(self, ['all', e].concat([].slice.call(args, 1)));
}
// Detect if new folder added to trigger for matching files within folder
if (e === 'added') {
if (helper.isDir(filepath)) {
// It's possible that between `isDir` and `readdirSync()` calls the `filepath`
// gets removed, which will result in `ENOENT` exception
var files;
try {
files = fs.readdirSync(filepath);
} catch (e) {
// Rethrow the error if it's anything other than `ENOENT`
if (e.code !== 'ENOENT') {
throw e;
}
files = [];
}
files.map(function (file) {
return path.join(filepath, file);
}).filter(function (file) {
return globule.isMatch(self._patterns, file, self.options);
}).forEach(function (file) {
self.emit('added', file);
});
}
}
return this;
};
// Close watchers
Gaze.prototype.close = function (_reset) {
var self = this;
Object.keys(self._watchers).forEach(function (file) {
self._watchers[file].close();
});
self._watchers = Object.create(null);
Object.keys(this._watched).forEach(function (dir) {
self._unpollDir(dir);
});
if (_reset !== false) {
self._watched = Object.create(null);
setTimeout(function () {
self.emit('end');
self.removeAllListeners();
clearInterval(self._keepalive);
}, delay + 100);
}
return self;
};
// Add file patterns to be watched
Gaze.prototype.add = function (files, done) {
if (typeof files === 'string') { files = [files]; }
this._patterns = helper.unique.apply(null, [this._patterns, files]);
files = globule.find(this._patterns, this.options);
this._addToWatched(files);
this.close(false);
this._initWatched(done);
};
// Dont increment patterns and dont call done if nothing added
Gaze.prototype._internalAdd = function (file, done) {
var files = [];
if (helper.isDir(file)) {
files = [helper.markDir(file)].concat(globule.find(this._patterns, this.options));
} else {
if (globule.isMatch(this._patterns, file, this.options)) {
files = [file];
}
}
if (files.length > 0) {
this._addToWatched(files);
this.close(false);
this._initWatched(done);
}
};
// Remove file/dir from `watched`
Gaze.prototype.remove = function (file) {
var self = this;
if (this._watched[file]) {
// is dir, remove all files
this._unpollDir(file);
delete this._watched[file];
} else {
// is a file, find and remove
Object.keys(this._watched).forEach(function (dir) {
var index = self._watched[dir].indexOf(file);
if (index !== -1) {
self._unpollFile(file);
self._watched[dir].splice(index, 1);
return false;
}
});
}
if (this._watchers[file]) {
this._watchers[file].close();
}
return this;
};
// Return watched files
Gaze.prototype.watched = function () {
return this._watched;
};
// Returns `watched` files with relative paths to process.cwd()
Gaze.prototype.relative = function (dir, unixify) {
var self = this;
var relative = Object.create(null);
var relDir, relFile, unixRelDir;
var cwd = this.options.cwd || process.cwd();
if (dir === '') { dir = '.'; }
dir = helper.markDir(dir);
unixify = unixify || false;
Object.keys(this._watched).forEach(function (dir) {
relDir = path.relative(cwd, dir) + path.sep;
if (relDir === path.sep) { relDir = '.'; }
unixRelDir = unixify ? helper.unixifyPathSep(relDir) : relDir;
relative[unixRelDir] = self._watched[dir].map(function (file) {
relFile = path.relative(path.join(cwd, relDir) || '', file || '');
if (helper.isDir(file)) {
relFile = helper.markDir(relFile);
}
if (unixify) {
relFile = helper.unixifyPathSep(relFile);
}
return relFile;
});
});
if (dir && unixify) {
dir = helper.unixifyPathSep(dir);
}
return dir ? relative[dir] || [] : relative;
};
// Adds files and dirs to watched
Gaze.prototype._addToWatched = function (files) {
var dirs = [];
for (var i = 0; i < files.length; i++) {
var file = files[i];
var filepath = path.resolve(this.options.cwd, file);
var dirname = (helper.isDir(file)) ? filepath : path.dirname(filepath);
dirname = helper.markDir(dirname);
// If a new dir is added
if (helper.isDir(file) && !(dirname in this._watched)) {
helper.objectPush(this._watched, dirname, []);
}
if (file.slice(-1) === '/') { filepath += path.sep; }
helper.objectPush(this._watched, path.dirname(filepath) + path.sep, filepath);
dirs.push(dirname);
}
dirs = helper.unique(dirs);
for (var k = 0; k < dirs.length; k++) {
dirname = dirs[k];
// add folders into the mix
var readdir = fs.readdirSync(dirname);
for (var j = 0; j < readdir.length; j++) {
var dirfile = path.join(dirname, readdir[j]);
if (fs.lstatSync(dirfile).isDirectory()) {
helper.objectPush(this._watched, dirname, dirfile + path.sep);
}
}
}
return this;
};
Gaze.prototype._watchDir = function (dir, done) {
var self = this;
var timeoutId;
try {
this._watchers[dir] = fs.watch(dir, function (event) {
// race condition. Let's give the fs a little time to settle down. so we
// don't fire events on non existent files.
clearTimeout(timeoutId);
timeoutId = setTimeout(function () {
// race condition. Ensure that this directory is still being watched
// before continuing.
if ((dir in self._watchers) && fs.existsSync(dir)) {
done(null, dir);
}
}, delay + 100);
});
this._watchers[dir].on('error', function (err) {
self._handleError(err);
});
} catch (err) {
return this._handleError(err);
}
return this;
};
Gaze.prototype._unpollFile = function (file) {
if (this._pollers[file]) {
fs.unwatchFile(file, this._pollers[file]);
delete this._pollers[file];
}
return this;
};
Gaze.prototype._unpollDir = function (dir) {
this._unpollFile(dir);
for (var i = 0; i < this._watched[dir].length; i++) {
this._unpollFile(this._watched[dir][i]);
}
};
Gaze.prototype._pollFile = function (file, done) {
var opts = { persistent: true, interval: this.options.interval };
if (!this._pollers[file]) {
this._pollers[file] = function (curr, prev) {
done(null, file);
};
try {
fs.watchFile(file, opts, this._pollers[file]);
} catch (err) {
return this._handleError(err);
}
}
return this;
};
// Initialize the actual watch on `watched` files
Gaze.prototype._initWatched = function (done) {
var self = this;
var cwd = this.options.cwd || process.cwd();
var curWatched = Object.keys(self._watched);
// if no matching files
if (curWatched.length < 1) {
// Defer to emitting to give a chance to attach event handlers.
setImmediate(function () {
self.emit('ready', self);
if (done) { done.call(self, null, self); }
self.emit('nomatch');
});
return;
}
helper.forEachSeries(curWatched, function (dir, next) {
dir = dir || '';
var files = self._watched[dir];
// Triggered when a watched dir has an event
self._watchDir(dir, function (event, dirpath) {
var relDir = cwd === dir ? '.' : path.relative(cwd, dir);
relDir = relDir || '';
fs.readdir(dirpath, function (err, current) {
if (err) { return self.emit('error', err); }
if (!current) { return; }
try {
// append path.sep to directories so they match previous.
current = current.map(function (curPath) {
if (fs.existsSync(path.join(dir, curPath)) && fs.lstatSync(path.join(dir, curPath)).isDirectory()) {
return curPath + path.sep;
} else {
return curPath;
}
});
} catch (err) {
// race condition-- sometimes the file no longer exists
}
// Get watched files for this dir
var previous = self.relative(relDir);
// If file was deleted
previous.filter(function (file) {
return current.indexOf(file) < 0;
}).forEach(function (file) {
if (!helper.isDir(file)) {
var filepath = path.join(dir, file);
self.remove(filepath);
self.emit('deleted', filepath);
}
});
// If file was added
current.filter(function (file) {
return previous.indexOf(file) < 0;
}).forEach(function (file) {
// Is it a matching pattern?
var relFile = path.join(relDir, file);
// Add to watch then emit event
self._internalAdd(relFile, function () {
self.emit('added', path.join(dir, file));
});
});
});
});
// Watch for change/rename events on files
files.forEach(function (file) {
if (helper.isDir(file)) { return; }
self._pollFile(file, function (err, filepath) {
if (err) {
self.emit('error', err);
return;
}
// Only emit changed if the file still exists
// Prevents changed/deleted duplicate events
if (fs.existsSync(filepath)) {
self.emit('changed', filepath);
}
});
});
next();
}, function () {
// Return this instance of Gaze
// delay before ready solves a lot of issues
setTimeout(function () {
self.emit('ready', self);
if (done) { done.call(self, null, self); }
}, delay + 100);
});
};
// If an error, handle it here
Gaze.prototype._handleError = function (err) {
if (err.code === 'EMFILE') {
return this.emit('error', new Error('EMFILE: Too many opened files.'));
}
return this.emit('error', err);
};