nw-dev/src/dev.coffee

A drop-in library for nw.js development

window.CRASHED = false

if process?
	nwgui = window.require "nw.gui"
	nwwin = nwgui.Window.get window
	
	# Get rid of the default error handler
	process.removeAllListeners "uncaughtException"
	
	# Add our own handler
	process.on "uncaughtException", (e)->
		unless window.CRASHED
			window.CRASHED = true
			console?.warn? "CRASH"
			nwwin.showDevTools()
		nwwin.show() if nwgui.App.manifest.window?.show is false
	
	# Keyboard shortcuts
	window.addEventListener "keydown", (e)->
		switch e.key ? e.keyIdentifier
			when "F12"
				nwwin.showDevTools()
			when "F5"
				window.location.reload()
	
	ignored = [/node_modules|npm-debug\.log|\.git|\.hg|\.svn/]
	ignore = document.currentScript.dataset.ignore
	ignored.push ignore if ignore
	
	# Live reload
	try
		chokidar = window.require "nw-dev/node_modules/chokidar/"
	catch err1
		try
			chokidar = window.require "chokidar"
		catch err2
			console.warn "Live reload disabled:", [err1.stack, err2.stack]
	
	if chokidar
		watcher = chokidar.watch ".", {ignored}
		# @TODO: watch linked dependencies and bundled dependencies
		# and make a package called watch-package
		watcher.on "change", (path)->
			watcher.close()
			
			# this could theoretically cause issues in very obscure cases
			# where caching behavior is relied upon in a separate page/context
			for own k of global.require.cache
				delete global.require.cache[k]
			# very obscure cases
			# overall, it's very helpful
			
			# this could cause issues in somewhat less obscure cases
			# where another page/context has listeners on this window
			nwwin.removeAllListeners()
			# but it fixes event listeners being leaked between reloads
			# which cause errors that wouldn't occur without reloading
			
			nwwin.closeDevTools()
			
			if path is "package.json"
				# we want to do a full reload
				
				fs = require "fs"
				pkg = JSON.parse fs.readFileSync "package.json", "utf8"
				
				# override the getter by redefining the property
				Object.defineProperty nwgui.App,
					"manifest"
					value: pkg
					configurable: yes # (so this will work a second time)
				
				{x, y} = nwwin
				width = window.innerWidth
				height = window.innerHeight
				window.close()
				newwin_options = {}
				newwin_options[k] = v for k, v of pkg.window
				newwin_options[k] = v for k, v of {x, y, width, height}
				newwin = nwgui.Window.open window.location.href, newwin_options
			else
				location?.reload()

window.onerror = (e)->
	unless window.CRASHED
		window.CRASHED = true
		console?.warn? "CRASH"
		nwwin?.showDevTools()
	return false