compiler.parse raises SyntaxErrors without line number information

[exarkun]

BPO	5064
Nosy	@nascheme, @birkenfeld, @benjaminp

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = 'https://github.com/nascheme'
closed_at = <Date 2009-09-04.07:56:42.449>
created_at = <Date 2009-01-26.03:25:43.435>
labels = ['type-bug', 'library']
title = 'compiler.parse raises SyntaxErrors without line number information'
updated_at = <Date 2009-09-04.07:56:42.447>
user = 'https://bugs.python.org/exarkun'

bugs.python.org fields:

activity = <Date 2009-09-04.07:56:42.447>
actor = 'georg.brandl'
assignee = 'nascheme'
closed = True
closed_date = <Date 2009-09-04.07:56:42.449>
closer = 'georg.brandl'
components = ['Library (Lib)']
creation = <Date 2009-01-26.03:25:43.435>
creator = 'exarkun'
dependencies = []
files = []
hgrepos = []
issue_num = 5064
keywords = []
message_count = 4.0
messages = ['80559', '80561', '88161', '92238']
nosy_count = 4.0
nosy_names = ['nascheme', 'georg.brandl', 'exarkun', 'benjamin.peterson']
pr_nums = []
priority = 'low'
resolution = 'wont fix'
stage = 'needs patch'
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue5064'
versions = []

[exarkun]

Sometimes a syntax error in source passed to compiler.parse´ causes a SyntaxError´ with lots of nice information to be raised:

>>> from compiler import parse
>>> try:
...     parse("def f(")
... except SyntaxError, e:
...     pass
...
>>> e
SyntaxError('unexpected EOF while parsing', (None, 1, 6, 'def f('))

But for other syntax errors, only a string message is provided, no
location information:

>>> try:
...     parse("def f(x=10, y): pass")
... except SyntaxError, f:
...     pass
...
>>> f
SyntaxError('non-default argument follows default argument',)
>>> try:
...     parse("f(x=10, y)")
... except SyntaxError, g:
...     pass
...
>>> g
SyntaxError('non-keyword arg after keyword arg',)
>>> 

On the other hand, the built in compiler produces exceptions which do
have this information in these cases.

The absence of the information makes the job of tools trying to operate
on Python source code more difficult (naively written, they'll simply
fail when they encounter one of these less informative exceptions).

[benjaminp]

Patches are welcome! The compiler package is deprecated in favor of
builtin AST.

[exarkun]

It seems a patch would be an enormous undertaking, as the data structure
returned by the parser does not include this information, and the parser
is written in C.

I'll just hack around this somehow. Don't expect a patch from me.

[birkenfeld]

In light of

The compiler package is deprecated in favor of builtin AST.

and

It seems a patch would be an enormous undertaking,

I guess it's best to close this as "won't fix".