watch(files, dirs, missing, startTime, options, callback, callbackUndelayed) {
if(!Array.isArray(files))
throw new Error("Invalid arguments: 'files'");
if(!Array.isArray(dirs))
throw new Error("Invalid arguments: 'dirs'");
if(!Array.isArray(missing))
throw new Error("Invalid arguments: 'missing'");
if(typeof callback !== "function")
throw new Error("Invalid arguments: 'callback'");
if(typeof startTime !== "number" && startTime)
throw new Error("Invalid arguments: 'startTime'");
if(typeof options !== "object")
throw new Error("Invalid arguments: 'options'");
if(typeof callbackUndelayed !== "function" && callbackUndelayed)
throw new Error("Invalid arguments: 'callbackUndelayed'");
const oldWatcher = this.watcher;
this.watcher = new Watchpack(options);
if(callbackUndelayed)
this.watcher.once("change", callbackUndelayed);
this.watcher.once("aggregated", (changes, removals) => {
changes = changes.concat(removals);
if(this.inputFileSystem && this.inputFileSystem.purge) {
this.inputFileSystem.purge(changes);
}
const times = this.watcher.getTimes();
callback(null,
changes.filter(file => files.indexOf(file) >= 0).sort(),
changes.filter(file => dirs.indexOf(file) >= 0).sort(),
changes.filter(file => missing.indexOf(file) >= 0).sort(), times, times);
});
this.watcher.watch(files.concat(missing), dirs.concat(missing), startTime);
if(oldWatcher) {
oldWatcher.close();
}
return {
close: () => {
if(this.watcher) {
this.watcher.close();
this.watcher = null;
}
},
pause: () => {
if(this.watcher) {
this.watcher.pause();
}
}
};
}
export default function onSourceChange(
{sourceDir, artifactsDir, onChange, shouldWatchFile}: Object): Watchpack {
// TODO: For network disks, we would need to add {poll: true}.
const watcher = new Watchpack();
const onFileChange = (filePath) => {
proxyFileChanges({artifactsDir, onChange, filePath, shouldWatchFile});
};
const executeImmediately = true;
watcher.on('change', debounce(onFileChange, 1000, executeImmediately));
log.debug(`Watching for file changes in ${sourceDir}`);
watcher.watch([], [sourceDir], Date.now());
// TODO: support interrupting the watcher on Windows.
// https://github.com/mozilla/web-ext/issues/225
process.on('SIGINT', () => watcher.close());
return watcher;
}