lib/faml/text_compiler.rb
# frozen_string_literal: true
require 'haml_parser/utils'
require 'strscan'
require_relative 'error'
module Faml
class TextCompiler
class InvalidInterpolation < Error
end
def initialize(escape_html: true)
@escape_html = escape_html
end
def compile(text, lineno, escape_html: @escape_html)
if self.class.contains_interpolation?(text)
compile_interpolation(text, lineno, escape_html: escape_html)
else
[:static, text]
end
end
INTERPOLATION_BEGIN = /(\\*)(#[\{$@])/o
def self.contains_interpolation?(text)
INTERPOLATION_BEGIN === text
end
private
def compile_interpolation(text, lineno, escape_html: @escape_html)
s = StringScanner.new(text)
temple = [:multi]
pos = s.pos
while s.scan_until(INTERPOLATION_BEGIN)
escapes = s[1].size
pre = s.string.byteslice(pos...(s.pos - s.matched.size))
temple << [:static, pre] << [:static, '\\' * (escapes / 2)]
if escapes.even?
# perform interpolation
if s[2] == '#{'
temple << [:escape, escape_html, [:dynamic, find_close_brace(s, lineno)]]
else
var = s[2][-1]
s.scan(/\w+/)
var << s.matched
temple << [:escape, escape_html, [:dynamic, var]]
end
else
# escaped
temple << [:static, s[2]]
end
pos = s.pos
end
temple << [:static, s.rest]
temple
end
INTERPOLATION_BRACE = /[\{\}]/o
def find_close_brace(scanner, lineno)
pos = scanner.pos
depth = HamlParser::Utils.balance(scanner, '{', '}')
if depth != 0
raise InvalidInterpolation.new(scanner.string, lineno)
else
scanner.string.byteslice(pos...(scanner.pos - 1))
end
end
end
end