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# New parser tests.
import py
import tokenize
import token
import StringIO
from pypy.interpreter.pyparser import parser, metaparser, pygram
from pypy.interpreter.pyparser.test.test_metaparser import MyGrammar
def test_char_set():
first = {5: None, 9: None, 100: None, 255:None}
p = parser.DFA(None, None, first)
for i in range(256):
assert p.could_match_token(i) == (i in first)
class SimpleParser(parser.Parser):
def parse(self, input):
self.prepare()
rl = StringIO.StringIO(input + "\n").readline
gen = tokenize.generate_tokens(rl)
for tp, value, begin, end, line in gen:
if self.add_token(parser.Token(tp, value, begin[0], begin[1], line)):
py.test.raises(StopIteration, gen.next)
return self.root
def tree_from_string(expected, gram):
def count_indent(s):
indent = 0
for char in s:
if char != " ":
break
indent += 1
return indent
last_newline_index = 0
for i, char in enumerate(expected):
if char == "\n":
last_newline_index = i
elif char != " ":
break
if last_newline_index:
expected = expected[last_newline_index + 1:]
base_indent = count_indent(expected)
assert not divmod(base_indent, 4)[1], "not using 4 space indentation"
lines = [line[base_indent:] for line in expected.splitlines()]
last_indent = 0
node_stack = []
for line in lines:
if not line.strip():
continue
data = line.split()
if data[0].isupper():
tp = getattr(token, data[0])
if len(data) == 2:
value = data[1].strip("\"")
elif tp == token.NEWLINE:
value = "\n"
else:
value = ""
n = parser.Terminal(tp, value, 0, 0)
else:
tp = gram.symbol_ids[data[0]]
n = parser.Nonterminal(tp)
new_indent = count_indent(line)
if new_indent >= last_indent:
if new_indent == last_indent and node_stack:
node_stack.pop()
if node_stack:
node_stack[-1].append_child(n)
node_stack.append(n)
else:
diff = last_indent - new_indent
pop_nodes = diff // 4 + 1
del node_stack[-pop_nodes:]
node_stack[-1].append_child(n)
node_stack.append(n)
last_indent = new_indent
return node_stack[0]
class TestParser:
def parser_for(self, gram, add_endmarker=True):
if add_endmarker:
gram += " NEWLINE ENDMARKER\n"
pgen = metaparser.ParserGenerator(gram)
g = pgen.build_grammar(MyGrammar)
return SimpleParser(g), g
def test_multiple_rules(self):
gram = """foo: 'next_rule' bar 'end' NEWLINE ENDMARKER
bar: NAME NUMBER\n"""
p, gram = self.parser_for(gram, False)
expected = """
foo
NAME "next_rule"
bar
NAME "a_name"
NUMBER "42"
NAME "end"
NEWLINE
ENDMARKER"""
input = "next_rule a_name 42 end"
assert tree_from_string(expected, gram) == p.parse(input)
def test_recursive_rule(self):
gram = """foo: NAME bar STRING NEWLINE ENDMARKER
bar: NAME [bar] NUMBER\n"""
p, gram = self.parser_for(gram, False)
expected = """
foo
NAME "hi"
bar
NAME "hello"
bar
NAME "a_name"
NUMBER "32"
NUMBER "42"
STRING "'string'"
NEWLINE
ENDMARKER"""
input = "hi hello a_name 32 42 'string'"
assert tree_from_string(expected, gram) == p.parse(input)
def test_symbol(self):
gram = """parent: first_child second_child NEWLINE ENDMARKER
first_child: NAME age
second_child: STRING
age: NUMBER\n"""
p, gram = self.parser_for(gram, False)
expected = """
parent
first_child
NAME "harry"
age
NUMBER "13"
second_child
STRING "'fred'"
NEWLINE
ENDMARKER"""
input = "harry 13 'fred'"
assert tree_from_string(expected, gram) == p.parse(input)
def test_token(self):
p, gram = self.parser_for("foo: NAME")
expected = """
foo
NAME "hi"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi")
py.test.raises(parser.ParseError, p.parse, "567")
p, gram = self.parser_for("foo: NUMBER NAME STRING")
expected = """
foo
NUMBER "42"
NAME "hi"
STRING "'bar'"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("42 hi 'bar'")
def test_optional(self):
p, gram = self.parser_for("foo: [NAME] 'end'")
expected = """
foo
NAME "hi"
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi end")
expected = """
foo
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("end")
def test_grouping(self):
p, gram = self.parser_for(
"foo: ((NUMBER NAME | STRING) | 'second_option')")
expected = """
foo
NUMBER "42"
NAME "hi"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("42 hi")
expected = """
foo
STRING "'hi'"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("'hi'")
expected = """
foo
NAME "second_option"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("second_option")
py.test.raises(parser.ParseError, p.parse, "42 a_name 'hi'")
py.test.raises(parser.ParseError, p.parse, "42 second_option")
def test_alternative(self):
p, gram = self.parser_for("foo: (NAME | NUMBER)")
expected = """
foo
NAME "hi"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi")
expected = """
foo
NUMBER "42"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("42")
py.test.raises(parser.ParseError, p.parse, "hi 23")
py.test.raises(parser.ParseError, p.parse, "23 hi")
py.test.raises(parser.ParseError, p.parse, "'some string'")
def test_keyword(self):
p, gram = self.parser_for("foo: 'key'")
expected = """
foo
NAME "key"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("key")
py.test.raises(parser.ParseError, p.parse, "")
p, gram = self.parser_for("foo: NAME 'key'")
expected = """
foo
NAME "some_name"
NAME "key"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("some_name key")
py.test.raises(parser.ParseError, p.parse, "some_name")
def test_repeaters(self):
p, gram = self.parser_for("foo: NAME+ 'end'")
expected = """
foo
NAME "hi"
NAME "bye"
NAME "nothing"
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi bye nothing end")
py.test.raises(parser.ParseError, p.parse, "end")
py.test.raises(parser.ParseError, p.parse, "hi bye")
p, gram = self.parser_for("foo: NAME* 'end'")
expected = """
foo
NAME "hi"
NAME "bye"
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi bye end")
py.test.raises(parser.ParseError, p.parse, "hi bye")
expected = """
foo
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("end")
p, gram = self.parser_for("foo: (NAME | NUMBER)+ 'end'")
expected = """
foo
NAME "a_name"
NAME "name_two"
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("a_name name_two end")
expected = """
foo
NUMBER "42"
NAME "name"
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("42 name end")
py.test.raises(parser.ParseError, p.parse, "end")
p, gram = self.parser_for("foo: (NAME | NUMBER)* 'end'")
expected = """
foo
NAME "hi"
NUMBER 42
NAME "end"
NEWLINE
ENDMARKER"""
assert tree_from_string(expected, gram) == p.parse("hi 42 end")
def test_optimized_terminal(self):
gram = """foo: bar baz 'end' NEWLINE ENDMARKER
bar: NAME
baz: NUMBER
"""
p, gram = self.parser_for(gram, False)
expected = """
foo
bar
NAME "a_name"
baz
NUMBER "42"
NAME "end"
NEWLINE
ENDMARKER"""
input = "a_name 42 end"
tree = p.parse(input)
assert tree_from_string(expected, gram) == tree
assert isinstance(tree, parser.Nonterminal)
assert isinstance(tree.get_child(0), parser.Nonterminal1)
assert isinstance(tree.get_child(1), parser.Nonterminal1)
def test_error_string(self):
p, gram = self.parser_for(
"foo: 'if' NUMBER '+' NUMBER"
)
info = py.test.raises(parser.ParseError, p.parse, "if 42")
info.value.expected_str is None
info = py.test.raises(parser.ParseError, p.parse, "if 42 42")
info.value.expected_str == '+'
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