1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
|
"""This module tests SyntaxErrors.
Here's an example of the sort of thing that is tested.
>>> def f(x):
... global x
Traceback (most recent call last):
SyntaxError: name 'x' is local and global
The tests are all raise SyntaxErrors. They were created by checking
each C call that raises SyntaxError. There are several modules that
raise these exceptions-- ast.c, compile.c, future.c, pythonrun.c, and
symtable.c.
The parser itself outlaws a lot of invalid syntax. None of these
errors are tested here at the moment. We should add some tests; since
there are infinitely many programs with invalid syntax, we would need
to be judicious in selecting some.
The compiler generates a synthetic module name for code executed by
doctest. Since all the code comes from the same module, a suffix like
[1] is appended to the module name, As a consequence, changing the
order of tests in this module means renumbering all the errors after
it. (Maybe we should enable the ellipsis option for these tests.)
In ast.c, syntax errors are raised by calling ast_error().
Errors from set_context():
TODO(jhylton): "assignment to None" is inconsistent with other messages
>>> obj.None = 1
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[1]>, line 1)
>>> None = 1
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[2]>, line 1)
It's a syntax error to assign to the empty tuple. Why isn't it an
error to assign to the empty list? It will always raise some error at
runtime.
>>> () = 1
Traceback (most recent call last):
SyntaxError: can't assign to () (<doctest test.test_syntax[3]>, line 1)
>>> f() = 1
Traceback (most recent call last):
SyntaxError: can't assign to function call (<doctest test.test_syntax[4]>, line 1)
>>> del f()
Traceback (most recent call last):
SyntaxError: can't delete function call (<doctest test.test_syntax[5]>, line 1)
>>> a + 1 = 2
Traceback (most recent call last):
SyntaxError: can't assign to operator (<doctest test.test_syntax[6]>, line 1)
>>> (x for x in x) = 1
Traceback (most recent call last):
SyntaxError: can't assign to generator expression (<doctest test.test_syntax[7]>, line 1)
>>> 1 = 1
Traceback (most recent call last):
SyntaxError: can't assign to literal (<doctest test.test_syntax[8]>, line 1)
>>> "abc" = 1
Traceback (most recent call last):
SyntaxError: can't assign to literal (<doctest test.test_syntax[9]>, line 1)
>>> `1` = 1
Traceback (most recent call last):
SyntaxError: can't assign to repr (<doctest test.test_syntax[10]>, line 1)
If the left-hand side of an assignment is a list or tuple, an illegal
expression inside that contain should still cause a syntax error.
This test just checks a couple of cases rather than enumerating all of
them.
>>> (a, "b", c) = (1, 2, 3)
Traceback (most recent call last):
SyntaxError: can't assign to literal (<doctest test.test_syntax[11]>, line 1)
>>> [a, b, c + 1] = [1, 2, 3]
Traceback (most recent call last):
SyntaxError: can't assign to operator (<doctest test.test_syntax[12]>, line 1)
>>> a if 1 else b = 1
Traceback (most recent call last):
SyntaxError: can't assign to conditional expression (<doctest test.test_syntax[13]>, line 1)
From compiler_complex_args():
>>> def f(None=1):
... pass
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[14]>, line 1)
From ast_for_arguments():
>>> def f(x, y=1, z):
... pass
Traceback (most recent call last):
SyntaxError: non-default argument follows default argument (<doctest test.test_syntax[15]>, line 1)
>>> def f(x, None):
... pass
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[16]>, line 1)
>>> def f(*None):
... pass
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[17]>, line 1)
>>> def f(**None):
... pass
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[18]>, line 1)
From ast_for_funcdef():
>>> def None(x):
... pass
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[19]>, line 1)
From ast_for_call():
>>> def f(it, *varargs):
... return list(it)
>>> L = range(10)
>>> f(x for x in L)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> f(x for x in L, 1)
Traceback (most recent call last):
SyntaxError: Generator expression must be parenthesized if not sole argument (<doctest test.test_syntax[23]>, line 1)
>>> f((x for x in L), 1)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> f(i0, i1, i2, i3, i4, i5, i6, i7, i8, i9, i10, i11,
... i12, i13, i14, i15, i16, i17, i18, i19, i20, i21, i22,
... i23, i24, i25, i26, i27, i28, i29, i30, i31, i32, i33,
... i34, i35, i36, i37, i38, i39, i40, i41, i42, i43, i44,
... i45, i46, i47, i48, i49, i50, i51, i52, i53, i54, i55,
... i56, i57, i58, i59, i60, i61, i62, i63, i64, i65, i66,
... i67, i68, i69, i70, i71, i72, i73, i74, i75, i76, i77,
... i78, i79, i80, i81, i82, i83, i84, i85, i86, i87, i88,
... i89, i90, i91, i92, i93, i94, i95, i96, i97, i98, i99,
... i100, i101, i102, i103, i104, i105, i106, i107, i108,
... i109, i110, i111, i112, i113, i114, i115, i116, i117,
... i118, i119, i120, i121, i122, i123, i124, i125, i126,
... i127, i128, i129, i130, i131, i132, i133, i134, i135,
... i136, i137, i138, i139, i140, i141, i142, i143, i144,
... i145, i146, i147, i148, i149, i150, i151, i152, i153,
... i154, i155, i156, i157, i158, i159, i160, i161, i162,
... i163, i164, i165, i166, i167, i168, i169, i170, i171,
... i172, i173, i174, i175, i176, i177, i178, i179, i180,
... i181, i182, i183, i184, i185, i186, i187, i188, i189,
... i190, i191, i192, i193, i194, i195, i196, i197, i198,
... i199, i200, i201, i202, i203, i204, i205, i206, i207,
... i208, i209, i210, i211, i212, i213, i214, i215, i216,
... i217, i218, i219, i220, i221, i222, i223, i224, i225,
... i226, i227, i228, i229, i230, i231, i232, i233, i234,
... i235, i236, i237, i238, i239, i240, i241, i242, i243,
... i244, i245, i246, i247, i248, i249, i250, i251, i252,
... i253, i254, i255)
Traceback (most recent call last):
SyntaxError: more than 255 arguments (<doctest test.test_syntax[25]>, line 1)
The actual error cases counts positional arguments, keyword arguments,
and generator expression arguments separately. This test combines the
three.
>>> f(i0, i1, i2, i3, i4, i5, i6, i7, i8, i9, i10, i11,
... i12, i13, i14, i15, i16, i17, i18, i19, i20, i21, i22,
... i23, i24, i25, i26, i27, i28, i29, i30, i31, i32, i33,
... i34, i35, i36, i37, i38, i39, i40, i41, i42, i43, i44,
... i45, i46, i47, i48, i49, i50, i51, i52, i53, i54, i55,
... i56, i57, i58, i59, i60, i61, i62, i63, i64, i65, i66,
... i67, i68, i69, i70, i71, i72, i73, i74, i75, i76, i77,
... i78, i79, i80, i81, i82, i83, i84, i85, i86, i87, i88,
... i89, i90, i91, i92, i93, i94, i95, i96, i97, i98, i99,
... i100, i101, i102, i103, i104, i105, i106, i107, i108,
... i109, i110, i111, i112, i113, i114, i115, i116, i117,
... i118, i119, i120, i121, i122, i123, i124, i125, i126,
... i127, i128, i129, i130, i131, i132, i133, i134, i135,
... i136, i137, i138, i139, i140, i141, i142, i143, i144,
... i145, i146, i147, i148, i149, i150, i151, i152, i153,
... i154, i155, i156, i157, i158, i159, i160, i161, i162,
... i163, i164, i165, i166, i167, i168, i169, i170, i171,
... i172, i173, i174, i175, i176, i177, i178, i179, i180,
... i181, i182, i183, i184, i185, i186, i187, i188, i189,
... i190, i191, i192, i193, i194, i195, i196, i197, i198,
... i199, i200, i201, i202, i203, i204, i205, i206, i207,
... i208, i209, i210, i211, i212, i213, i214, i215, i216,
... i217, i218, i219, i220, i221, i222, i223, i224, i225,
... i226, i227, i228, i229, i230, i231, i232, i233, i234,
... i235, i236, i237, i238, i239, i240, i241, i242, i243,
... (x for x in i244), i245, i246, i247, i248, i249, i250, i251,
... i252=1, i253=1, i254=1, i255=1)
Traceback (most recent call last):
SyntaxError: more than 255 arguments (<doctest test.test_syntax[26]>, line 1)
>>> f(lambda x: x[0] = 3)
Traceback (most recent call last):
SyntaxError: lambda cannot contain assignment (<doctest test.test_syntax[27]>, line 1)
The grammar accepts any test (basically, any expression) in the
keyword slot of a call site. Test a few different options.
>>> f(x()=2)
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (<doctest test.test_syntax[28]>, line 1)
>>> f(a or b=1)
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (<doctest test.test_syntax[29]>, line 1)
>>> f(x.y=1)
Traceback (most recent call last):
SyntaxError: keyword can't be an expression (<doctest test.test_syntax[30]>, line 1)
From ast_for_expr_stmt():
>>> (x for x in x) += 1
Traceback (most recent call last):
SyntaxError: augmented assignment to generator expression not possible (<doctest test.test_syntax[31]>, line 1)
>>> None += 1
Traceback (most recent call last):
SyntaxError: assignment to None (<doctest test.test_syntax[32]>, line 1)
>>> f() += 1
Traceback (most recent call last):
SyntaxError: illegal expression for augmented assignment (<doctest test.test_syntax[33]>, line 1)
"""
import re
import unittest
import warnings
from test import test_support
class SyntaxTestCase(unittest.TestCase):
def _check_error(self, code, errtext,
filename="<testcase>", mode="exec", subclass=None):
"""Check that compiling code raises SyntaxError with errtext.
errtest is a regular expression that must be present in the
test of the exception raised. If subclass is specified it
is the expected subclass of SyntaxError (e.g. IndentationError).
"""
try:
compile(code, filename, mode)
except SyntaxError, err:
if subclass and not isinstance(err, subclass):
self.fail("SyntaxError is not a %s" % subclass.__name__)
mo = re.search(errtext, str(err))
if mo is None:
self.fail("SyntaxError did not contain '%r'" % (errtext,))
else:
self.fail("compile() did not raise SyntaxError")
def test_assign_call(self):
self._check_error("f() = 1", "assign")
def test_assign_del(self):
self._check_error("del f()", "delete")
def test_global_err_then_warn(self):
# Bug tickler: The SyntaxError raised for one global statement
# shouldn't be clobbered by a SyntaxWarning issued for a later one.
source = re.sub('(?m)^ *:', '', """\
:def error(a):
: global a # SyntaxError
:def warning():
: b = 1
: global b # SyntaxWarning
:""")
warnings.filterwarnings(action='ignore', category=SyntaxWarning)
self._check_error(source, "global")
warnings.filters.pop(0)
def test_break_outside_loop(self):
self._check_error("break", "outside loop")
def test_delete_deref(self):
source = re.sub('(?m)^ *:', '', """\
:def foo(x):
: def bar():
: print x
: del x
:""")
self._check_error(source, "nested scope")
def test_unexpected_indent(self):
self._check_error("foo()\n bar()\n", "unexpected indent",
subclass=IndentationError)
def test_no_indent(self):
self._check_error("if 1:\nfoo()", "expected an indented block",
subclass=IndentationError)
def test_bad_outdent(self):
self._check_error("if 1:\n foo()\n bar()",
"unindent does not match .* level",
subclass=IndentationError)
def test_main():
test_support.run_unittest(SyntaxTestCase)
from test import test_syntax
test_support.run_doctest(test_syntax, verbosity=True)
if __name__ == "__main__":
test_main()
|