from libs.evaluators import PrefixEvaluator
from argparse import ArgumentParser
import os.path
parser = ArgumentParser(
description='Process text files with prefix expressions per newline')
parser.add_argument('-file', dest='filename', required=False, metavar="FILE")
filename = parser.parse_args().filename
pre_eval = PrefixEvaluator()
with open(filename, 'r') as f:
for line in f:
print pre_eval.evaluate(line)
def test_expression_parser():
peval = PrefixEvaluator()
pre_parsed = '* + 2 3 4'
properly_parsed = ['*', '+', 2, 3, 4]
assert peval._parsed_expression(pre_parsed) == properly_parsed
def test_is_integer():
peval = PrefixEvaluator()
string_int_list = [str(i) for i in range(0,11)] # ['0', '1',...,'10']
for string in string_int_list:
assert peval._is_integer(string)
def test_evaluation():
peval = PrefixEvaluator()
test_string = '* + 2 3 4'
assert peval.evaluate(test_string) == 20
def test_string_subtraction():
peval = PrefixEvaluator()
assert peval._eval_string_op['-'](9,8) == 9 - 8
def test_string_addition():
peval = PrefixEvaluator()
assert peval._eval_string_op['+'](6,7) == 6 + 7
def test_string_division():
peval = PrefixEvaluator()
assert peval._eval_string_op['/'](4,5) == 4 / 5
def test_string_multiplication():
peval = PrefixEvaluator()
assert peval._eval_string_op['*'](2,3) == 2 * 3