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comparison python/testpyy.py @ 194:b01429a5d695

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Fixed test
author Windel Bouwman
date Wed, 29 May 2013 22:36:37 +0200
parents 6cd6260789a1
children 37ac6c016e0f
comparison
equal deleted inserted replaced
193:f091e7d70996 194:b01429a5d695
1 import unittest, pprint 1 import unittest, pprint
2 from pyyacc import Grammar, Item, EOF, ParserGenerationException 2 from pyyacc import Grammar, Item, ParserGenerationException, ParserException, EPS, EOF
3 from ppci import Token 3 from ppci import Token
4 4
5 def genTokens(lst): 5 def genTokens(lst):
6 for t in lst: 6 for t in lst:
7 yield Token(t, t, 0) 7 yield Token(t, t)
8 8
9 class testLR(unittest.TestCase): 9 class testLR(unittest.TestCase):
10 def setUp(self): 10 """ Test basic LR(1) parser generator constructs """
11 pass
12
13 def testSimpleGrammar(self): 11 def testSimpleGrammar(self):
14 # 1. define a simple grammar: 12 # 1. define a simple grammar:
15 g = Grammar(['EOF', 'identifier', '(', ')', '+', '*']) 13 g = Grammar(['identifier', '(', ')', '+', '*'])
16 g.add_production('input', ['expression']) 14 g.add_production('input', ['expression'])
17 g.add_production('expression', ['term']) 15 g.add_production('expression', ['term'])
18 g.add_production('expression', ['expression', '+', 'term']) 16 g.add_production('expression', ['expression', '+', 'term'])
19 g.add_production('term', ['factor']) 17 g.add_production('term', ['factor'])
20 g.add_production('term', ['term', '*', 'factor']) 18 g.add_production('term', ['term', '*', 'factor'])
28 # 4. feed input: 26 # 4. feed input:
29 p.parse(tokens) 27 p.parse(tokens)
30 def testReduceReduceConflict(self): 28 def testReduceReduceConflict(self):
31 """ Check if a reduce-reduce conflict is detected """ 29 """ Check if a reduce-reduce conflict is detected """
32 # Define a grammar with an obvious reduce-reduce conflict: 30 # Define a grammar with an obvious reduce-reduce conflict:
33 g = Grammar([EOF, 'id']) 31 g = Grammar(['id'])
34 g.add_production('goal', ['a']) 32 g.add_production('goal', ['a'])
35 g.add_production('a', ['b']) 33 g.add_production('a', ['b'])
36 g.add_production('a', ['c']) 34 g.add_production('a', ['c'])
37 g.add_production('b', ['id']) 35 g.add_production('b', ['id'])
38 g.add_production('c', ['id']) 36 g.add_production('c', ['id'])
39 g.start_symbol = 'goal' 37 g.start_symbol = 'goal'
40 with self.assertRaises(ParserGenerationException): 38 with self.assertRaises(ParserGenerationException):
41 p = g.genParser() 39 p = g.genParser()
42 def testShiftReduceConflict(self): 40 def testShiftReduceConflict(self):
43 g = Grammar([EOF, 'if', 'then', 'else']) 41 """ Must be handled automatically by doing shift """
44 g.add_production('if_stmt', ['if', 'then']) 42 g = Grammar([EOF, 'if', 'then', 'else', 'ass'])
45 g.add_production('if_stmt', ['if', 'then', 'else']) 43 # Ambiguous grammar:
46 g.add_production('stmt', ['if_stmt', 'else']) 44 g.add_production('if_stmt', ['if', 'then', 'stmt'])
45 g.add_production('if_stmt', ['if', 'then', 'stmt', 'else', 'stmt'])
46 g.add_production('stmt', ['if_stmt'])
47 g.add_production('stmt', ['ass'])
47 g.start_symbol = 'stmt' 48 g.start_symbol = 'stmt'
48 with self.assertRaises(ParserGenerationException): 49 p = g.genParser()
49 g.genParser() 50 # Ambiguous program:
51 tokens = genTokens(['if', 'then','if', 'then', 'ass', 'else', 'ass' ])
52 p.parse(tokens)
53
50 def testUndefinedTerminal(self): 54 def testUndefinedTerminal(self):
51 """ Test correct behavior when a terminal is undefined """ 55 """ Test correct behavior when a terminal is undefined """
52 g = Grammar([EOF, 'b']) 56 g = Grammar(['b'])
53 g.add_production('goal', ['a']) 57 g.add_production('goal', ['a'])
54 g.add_production('a', ['b']) 58 g.add_production('a', ['b'])
55 g.add_production('a', ['c']) 59 g.add_production('a', ['c'])
56 g.start_symbol = 'goal' 60 g.start_symbol = 'goal'
57 with self.assertRaises(ParserGenerationException): 61 with self.assertRaises(ParserGenerationException):
63 with self.assertRaises(ParserGenerationException): 67 with self.assertRaises(ParserGenerationException):
64 g.add_production('b', ['c']) # Not allowed 68 g.add_production('b', ['c']) # Not allowed
65 g.add_production('a', ['c']) 69 g.add_production('a', ['c'])
66 g.start_symbol = 'goal' 70 g.start_symbol = 'goal'
67 g.genParser() 71 g.genParser()
72 def testEmpty(self):
73 """ Test empty token stream """
74 g = Grammar([','])
75 g.add_production('input', [','])
76 g.start_symbol = 'input'
77 p = g.genParser()
78 tokens = genTokens([])
79 with self.assertRaises(ParserException):
80 p.parse(tokens)
81
82 def testEps(self):
83 """ Test epsilon terminal """
84 g = Grammar(['a', 'b'])
85 g.add_production('input', ['optional_a', 'b'])
86 g.add_production('optional_a', ['a'])
87 g.add_production('optional_a', [])
88 g.start_symbol = 'input'
89 p = g.genParser()
90 tokens = genTokens(['b'])
91 p.parse(tokens)
92
93 def testEps2(self):
94 g = Grammar(['id', ':'])
95 g.add_production('input', ['opt_lab', 'ins', 'op1'])
96 g.add_production('input', ['ins', 'op1'])
97 g.add_production('opt_lab', ['id', ':'])
98 g.add_production('ins', ['id'])
99 g.add_production('op1', ['id'])
100 g.start_symbol = 'input'
101 p = g.genParser()
102 tokens = genTokens(['id', ':', 'id', 'id']) # i.e. "lab_0: inc rax"
103 p.parse(tokens)
104 tokens = genTokens(['id', 'id']) # i.e. "inc rax"
105 p.parse(tokens)
106
68 107
69 class testExpressionGrammar(unittest.TestCase): 108 class testExpressionGrammar(unittest.TestCase):
70 def setUp(self): 109 def setUp(self):
71 g = Grammar(['EOF', 'identifier', '(', ')', '+', '*', 'num']) 110 g = Grammar(['EOF', 'identifier', '(', ')', '+', '*', 'num'])
72 g.add_production('input', ['expression']) 111 g.add_production('input', ['expression'])