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# -*- coding: utf-8 -*-
#######################################################################
# Name: test_peg_parser
# Purpose: Test for parser constructed using PEG textual grammars.
# Author: Igor R. Dejanović <igor DOT dejanovic AT gmail DOT com>
# Copyright: (c) 2014 Igor R. Dejanović <igor DOT dejanovic AT gmail DOT com>
# License: MIT License
#######################################################################
import pytest
from arpeggio import Sequence, NonTerminal
from arpeggio.peg import ParserPEG
grammar = '''
number <- r'\d*\.\d*|\d+';
factor <- ("+" / "-")?
(number / "(" expression ")");
term <- factor (( "*" / "/") factor)*;
expression <- term (("+" / "-") term)*;
calc <- expression+ EOF;
'''
def test_construct_parser():
parser = ParserPEG(grammar, 'calc')
assert parser.parser_model.rule_name == 'calc'
assert isinstance(parser.parser_model, Sequence)
assert parser.parser_model.nodes[0].name == 'OneOrMore'
def test_parse_input():
parser = ParserPEG(grammar, 'calc')
input = "4+5*7/3.45*-45*(2.56+32)/-56*(2-1.34)"
result = parser.parse(input)
assert isinstance(result, NonTerminal)
assert str(result) == "4 | + | 5 | * | 7 | / | 3.45 | * | - | 45 | * | ( | 2.56 | + | 32 | ) | / | - | 56 | * | ( | 2 | - | 1.34 | ) | "
assert repr(result) == "[ [ [ [ number '4' [0] ] ], '+' [1], [ [ number '5' [2] ], '*' [3], [ number '7' [4] ], '/' [5], [ number '3.45' [6] ], '*' [10], [ '-' [11], number '45' [12] ], '*' [14], [ '(' [15], [ [ [ number '2.56' [16] ] ], '+' [20], [ [ number '32' [21] ] ] ], ')' [23] ], '/' [24], [ '-' [25], number '56' [26] ], '*' [28], [ '(' [29], [ [ [ number '2' [30] ] ], '-' [31], [ [ number '1.34' [32] ] ] ], ')' [36] ] ] ], EOF [37] ]"
def test_reduce_tree():
parser = ParserPEG(grammar, 'calc', reduce_tree=True)
input = "4+5*7/3.45*-45*(2.56+32)/-56*(2-1.34)"
result = parser.parse(input)
assert isinstance(result, NonTerminal)
assert str(result) == "4 | + | 5 | * | 7 | / | 3.45 | * | - | 45 | * | ( | 2.56 | + | 32 | ) | / | - | 56 | * | ( | 2 | - | 1.34 | ) | "
assert repr(result) == "[ [ number '4' [0], '+' [1], [ number '5' [2], '*' [3], number '7' [4], '/' [5], number '3.45' [6], '*' [10], [ '-' [11], number '45' [12] ], '*' [14], [ '(' [15], [ number '2.56' [16], '+' [20], number '32' [21] ], ')' [23] ], '/' [24], [ '-' [25], number '56' [26] ], '*' [28], [ '(' [29], [ number '2' [30], '-' [31], number '1.34' [32] ], ')' [36] ] ] ], EOF [37] ]"