Move exec, crash, and file IO to "helpers" autoload node

game.gd

@@ -2,7 +2,6 @@ extends Node
 
 var tmp_prefix = _tmp_prefix()
 var global_shell
-var debug_file_io = false
 var fake_editor
 
 var _file = "user://savegame.json"
@@ -39,40 +38,15 @@ func load_state() -> bool:
 	savegame.close()
 	return true
 	
-	
 func copy_file_to_game_env(filename):
-	
 	# Copy fake-editor to tmp directory (because the original might be in a .pck file).
 	var file_outside = tmp_prefix + filename
 	var file_inside = "/tmp/"+filename
-	var content = game.read_file("res://scripts/"+filename, "")
-	if content.empty():
-		push_error(filename + " could not be read.")
-	write_file(file_outside, content)
+	var content = helpers.read_file("res://scripts/"+filename)
+	helpers.write_file(file_outside, content)
 	global_shell.run("chmod u+x " + file_inside)
 	return file_inside
 
-func read_file(path, fallback_string):
-	if debug_file_io:
-		print("reading " + path)
-	var file = File.new()
-	var open_status = file.open(path, File.READ)
-	if open_status == OK:
-		var content = file.get_as_text()
-		file.close()
-		return content
-	else:
-		return fallback_string
-
-func write_file(path, content):
-	if debug_file_io:
-		print("writing " + path)
-	var file = File.new()
-	file.open(path, File.WRITE)
-	file.store_string(content)
-	file.close()
-	return true
-
 func _tmp_prefix():
 	var os = OS.get_name()
 	if os == "X11":
@@ -80,26 +54,6 @@ func _tmp_prefix():
 	elif os == "Windows":
 		# For some reason, this command outputs a space in the end? We remove it.
 		# Also, Godot's default is to use forward slashes for everything.
-		return exec("echo", ["%TEMP%"]).replacen("\\", "/").replace(" \n", "/")
+		return helpers.exec("echo", ["%TEMP%"]).replacen("\\", "/").replace(" \n", "/")
 	else:
-		push_error("Unsupported OS")
-		get_tree().quit()
-
-# Run a simple command with arguments, blocking, using OS.execute.
-func exec(command, args=[]):
-	var debug = false
-	
-	if debug:
-		print("exec: %s [%s]" % [command, PoolStringArray(args).join(", ")])
-		
-	var output = []
-	var exit_code = OS.execute(command, args, true, output, true)
-	output = output[0]
-	
-	if exit_code != 0:
-		push_error("OS.execute failed: %s [%s] Output: %s" % [command, PoolStringArray(args).join(", "), output])
-	
-	if debug:
-		print(output)
-
-	return output
+		helpers.crash("Unsupported OS: %s" % os)

helpers.gd

@@ -0,0 +1,54 @@
+extends Node
+
+var debug_file_io = false
+
+# Crash the game and display the error message.
+func crash(message):
+	push_error(message)
+	print("Fatal error: " + message)
+	get_tree().quit()
+
+# Run a simple command with arguments, blocking, using OS.execute.
+func exec(command, args=[], crash_on_fail=true):
+	var debug = false
+	
+	if debug:
+		print("exec: %s [%s]" % [command, PoolStringArray(args).join(", ")])
+		
+	var output = []
+	var exit_code = OS.execute(command, args, true, output, true)
+	output = output[0]
+	
+	if exit_code != 0 and crash_on_fail:
+		helpers.crash("OS.execute failed: %s [%s] Output: %s" % [command, PoolStringArray(args).join(", "), output])
+	
+	if debug:
+		print(output)
+
+	return output
+
+# Return the contents of a file. If no fallback_string is provided, crash when
+# the file doesn't exist.
+func read_file(path, fallback_string=null):
+	if debug_file_io:
+		print("reading " + path)
+	var file = File.new()
+	var open_status = file.open(path, File.READ)
+	if open_status == OK:
+		var content = file.get_as_text()
+		file.close()
+		return content
+	else:
+		if fallback_string != null:
+			return fallback_string
+		else:
+			helpers.crash("File %s could not be read, and has no fallback" % path)
+
+func write_file(path, content):
+	if debug_file_io:
+		print("writing " + path)
+	var file = File.new()
+	file.open(path, File.WRITE)
+	file.store_string(content)
+	file.close()
+	return true

main.gd

@@ -67,13 +67,13 @@ func list_levels():
 	
 	var final_level_sequence = []
 	
-	var level_sequence = Array(game.read_file("res://levels/%s/sequence" % chapter, "").split("\n"))
+	var level_sequence = Array(helpers.read_file("res://levels/%s/sequence" % chapter, "").split("\n"))
 	
 	for level in level_sequence:
 		if level == "":
 			continue
 		if not levels.has(level):
-			push_error("Level '%s' is specified in the sequence, but could not be found" % level)
+			helpers.crash("Level '%s' is specified in the sequence, but could not be found" % level)
 		levels.erase(level)
 		final_level_sequence.push_back(level)
 	
@@ -105,7 +105,7 @@ func load_level(id):
 	var active_script = level_prefix+level+"/start"
 	
 	var description_file = level_prefix+level+"/description"
-	var description = game.read_file(description_file, "no description")
+	var description = helpers.read_file(description_file, "(no description)")
 	
 	# Surround all lines indented with four spaces with [code] tags.
 	var monospace_regex = RegEx.new()
@@ -114,7 +114,7 @@ func load_level(id):
 	level_description.bbcode_text = description
 	
 	var congrats_file = level_prefix+level+"/congrats"
-	var congrats = game.read_file(congrats_file, "Good job, you solved the level!\n\nFeel free to try a few more things or click 'Next Level'.")
+	var congrats = helpers.read_file(congrats_file, "Good job, you solved the level!\n\nFeel free to try a few more things or click 'Next Level'.")
 	level_congrats.bbcode_text = congrats
 	
 	level_name.text = level
@@ -123,18 +123,16 @@ func load_level(id):
 	# Make sure that active_repository is in a temporary directory.
 	var expected_prefix = "/tmp"
 	if active_repository_path.substr(0,4) != expected_prefix:
-		push_error("Refusing to delete a directory that does not start with %s" % expected_prefix)
-		get_tree().quit()
+		helpers.crash("Refusing to delete directory %s that does not start with %s" % [active_repository_path, expected_prefix])
 	if goal_repository_path.substr(0,4) != expected_prefix:
-		push_error("Refusing to delete a directory that does not start with %s" % expected_prefix)
-		get_tree().quit()
+		helpers.crash("Refusing to delete directory %s that does not start with %s" % [goal_repository_path, expected_prefix])
 	
 	# Danger zone!
 	game.global_shell.run("rm -rf '%s'" % active_repository_path)
 	game.global_shell.run("rm -rf '%s'" % goal_repository_path)
 		
-	var goal_script_content = game.read_file(goal_script, "")
-	var active_script_content = game.read_file(active_script, "")
+	var goal_script_content = helpers.read_file(goal_script, "")
+	var active_script_content = helpers.read_file(active_script, "")
 	construct_repo(active_script_content +"\n"+ goal_script_content, goal_repository_path)
 	construct_repo(active_script_content, active_repository_path)
 	
@@ -143,8 +141,8 @@ func load_level(id):
 	
 	var win_script = level_prefix+level+"/win"
 	var win_script_target = game.tmp_prefix+"/win"
-	var win_script_content = game.read_file(win_script, "exit 1\n")
-	game.write_file(win_script_target, win_script_content)
+	var win_script_content = helpers.read_file(win_script, "exit 1\n")
+	helpers.write_file(win_script_target, win_script_content)
 	
 	terminal.clear()
 	
@@ -171,7 +169,7 @@ func construct_repo(script_content, path):
 	
 	var script_path_outside = game.tmp_prefix+"/git-hydra-script"
 	var script_path = "/tmp/git-hydra-script"
-	game.write_file(script_path_outside, script_content)
+	helpers.write_file(script_path_outside, script_content)
 	
 	game.global_shell.run("mkdir " + path)
 	game.global_shell.cd(path)

project.godot

@@ -26,6 +26,7 @@ run/main_scene="res://main.tscn"
 [autoload]
 
 game="*res://game.gd"
+helpers="*res://helpers.gd"
 
 [display]
 

shell.gd

@@ -49,7 +49,7 @@ func run(command):
 	# 
 	hacky_command = '"\''+hacky_command.replace("'", "'\"'\"'")+'\'"'
 	
-	var output = game.exec(_shell_binary(), ["-c",  hacky_command])
+	var output = helpers.exec(_shell_binary(), ["-c",  hacky_command], false)
 	
 	if debug:
 		print(output)
@@ -64,8 +64,7 @@ func _shell_binary():
 	elif os == "Windows":
 		return "dependencies\\windows\\git\\bin\\bash.exe"
 	else:
-		push_error("Unsupported OS")
-		get_tree().quit()
+		helpers.crash("Unsupported OS: %s" % os)
 
 var _t	
 func run_async(command):

tcp_server.gd

@@ -18,7 +18,7 @@ func _process(_delta):
 	if _s.is_connection_available():
 		if _connected:
 			_c.disconnect_from_host()
-			push_error("Dropping active connection")
+			helpers.crash("Dropping active connection")
 		_c = _s.take_connection()
 		_connected = true
 		print("connected!")
@@ -38,4 +38,4 @@ func send(text):
 		text += "\n"
 		_c.put_data(text.to_utf8())
 	else:
-		push_error("Trying to send data on closed connection")
+		helpers.crash("Trying to send data on closed connection")

terminal.gd

@@ -29,7 +29,7 @@ func _ready():
 	
 	var error = $TextEditor.connect("hide", self, "editor_closed")
 	if error != OK:
-		push_error("Could not connect TextEditor's hide signal")
+		helpers.crash("Could not connect TextEditor's hide signal")
 	input.grab_focus()
 	
 	var all_git_commands = repository.shell.run("git help -a | grep \"^ \\+[a-z-]\\+ \" -o")

text_editor.gd

@@ -22,10 +22,7 @@ func open(filename):
 	path = filename
 	
 	var fixme_path = game.tmp_prefix+"/active/"
-	var content = game.read_file(fixme_path+filename, "[ERROR_FAKE_EDITOR]")
-	if content == "[ERROR_FAKE_EDITOR]":
-		push_error("Specified file could not be read.")
-		get_tree().quit()
+	var content = helpers.read_file(fixme_path+filename)
 	text = content
 	
 	show()
@@ -33,7 +30,7 @@ func open(filename):
 
 func save():
 	var fixme_path = game.tmp_prefix+"/active/"
-	game.write_file(fixme_path+path, text)
+	helpers.write_file(fixme_path+path, text)
 	close()
 
 func close():