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import parser
import pprint
import sys
from parser import expr, suite, sequence2ast
from test_support import verbose
#
# First, we test that we can generate trees from valid source fragments,
# and that these valid trees are indeed allowed by the tree-loading side
# of the parser module.
#
def roundtrip(f, s):
print s
st1 = f(s)
t = st1.totuple()
st2 = parser.sequence2ast(t)
print "Expressions:"
roundtrip(expr, "foo(1)")
roundtrip(expr, "[1, 2, 3]")
roundtrip(expr, "[x**3 for x in range(20)]")
roundtrip(expr, "[x**3 for x in range(20) if x % 3]")
roundtrip(expr, "foo(*args)")
roundtrip(expr, "foo(*args, **kw)")
roundtrip(expr, "foo(**kw)")
roundtrip(expr, "foo(key=value)")
roundtrip(expr, "foo(key=value, *args)")
roundtrip(expr, "foo(key=value, *args, **kw)")
roundtrip(expr, "foo(key=value, **kw)")
roundtrip(expr, "foo(a, b, c, *args)")
roundtrip(expr, "foo(a, b, c, *args, **kw)")
roundtrip(expr, "foo(a, b, c, **kw)")
roundtrip(expr, "foo + bar")
print
print "Statements:"
roundtrip(suite, "print")
roundtrip(suite, "print 1")
roundtrip(suite, "print 1,")
roundtrip(suite, "print >>fp")
roundtrip(suite, "print >>fp, 1")
roundtrip(suite, "print >>fp, 1,")
#
# Second, we take *invalid* trees and make sure we get ParserError
# rejections for them.
#
print
print "Invalid parse trees:"
def check_bad_tree(tree, label):
print
print label
try:
sequence2ast(tree)
except parser.ParserError:
print "caught expected exception for invalid tree"
pass
else:
print "test failed: did not properly detect invalid tree:"
pprint.pprint(tree)
# not even remotely valid:
check_bad_tree((1, 2, 3), "<junk>")
# print >>fp,
tree = \
(257,
(264,
(265,
(266,
(268,
(1, 'print'),
(35, '>>'),
(290,
(291,
(292,
(293,
(295,
(296,
(297,
(298, (299, (300, (301, (302, (303, (1, 'fp')))))))))))))),
(12, ','))),
(4, ''))),
(0, ''))
check_bad_tree(tree, "print >>fp,")
# a,,c
tree = \
(258,
(311,
(290,
(291,
(292,
(293,
(295,
(296, (297, (298, (299, (300, (301, (302, (303, (1, 'a')))))))))))))),
(12, ','),
(12, ','),
(290,
(291,
(292,
(293,
(295,
(296, (297, (298, (299, (300, (301, (302, (303, (1, 'c'))))))))))))))),
(4, ''),
(0, ''))
check_bad_tree(tree, "a,,c")
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