from io import StringIO
from assembler.context import FileContext


def test_getc_ungetc():
	data = StringIO("abc\ndefg")
	context = FileContext(data)

	assert context.getc() == "a"
	assert context.getc() == "b"
	assert context._line == 0
	assert context._column == 2
	assert context.getc() == "c"
	assert context.getc() == "\n"
	assert context.getc() == "d"
	assert context._line == 1
	assert context._column == 1

	context.ungetc("d")
	context.ungetc("\n")

	assert context._column == 3
	assert context._line == 0
	assert context.getc() == "\n"