Format message depending of its severity level

Property definitions

logger $ Formatter :: format
	# Format `message` depending of its severity `level`
	fun format(level: Int, message: Writable): Writable do return message
lib/logger/logger.nit:318,2--319,70

logger $ DefaultFormatter :: format
	redef fun format(level, message) do
		var string = message.write_to_string

		if level == fatal_level then
			string = "Fatal: {string}"
		else if level == error_level then
			string = "Error: {string}"
		else if level == warn_level then
			string = "Warning: {string}"
		else if level == info_level then
			string = "Info: {string}"
		else if level == debug_level then
			string = "Debug: {string}"
		end

		if no_color then return string

		if level == fatal_level then
			return string.red
		else if level == error_level then
			return string.red
		else if level == warn_level then
			return string.yellow
		else if level == info_level then
			return string.purple
		else if level == debug_level then
			return string.blue
		end

		return string
	end
lib/logger/logger.nit:336,2--366,4

popcorn $ PopFormatter :: format
	redef fun format(level, message) do
		var string = message.write_to_string

		if level == fatal_level then
			string = "[FATAL] {string}"
		else if level == error_level then
			string = "[ERROR] {string}"
		else if level == warn_level then
			string = "[WARN] {string}"
		else if level == info_level then
			string = "[INFO] {string}"
		else if level == debug_level then
			string = "[DEBUG] {string}"
		end

		if no_color then return string

		if level == fatal_level then
			return string.red
		else if level == error_level then
			return string.red
		else if level == warn_level then
			return string.yellow
		else if level == info_level then
			return string.blue
		else if level == debug_level then
			return string.gray
		end

		return string
	end
lib/popcorn/pop_logging.nit:64,2--94,4