Alexey Neyman <sti...@att.net> писал в своём письме Wed, 17 Mar 2010
00:05:01 +0300:
Hi all,
The svn_repos_history2() function allows the history_func() to return a
special error, SVN_ERR_CEASE_INVOCATION, to stop the search. This is not
supported in Python bindings, though: attempt to return
core.SVN_ERR_CEASE_INVOCATION from the history receiver results in an
exception:
def history_lookup(path, rev, pool):
return core.SVN_ERR_CEASE_INVOCATION
repos.svn_repos_history2(..., history_lookup, ...)
svn.core.SubversionException: ('Python callback returned an invalid
object', 20014)
Indeed, svn_swig_py_repos_history_func() only expects a return of None.
This patch allows the callback to return core.SVN_ERR_CEASE_INVOCATION.
Currently, this is only used in svn_repos_history2() - apparently, it's
the only function that supports SVN_ERR_CEASE_INVOCATION. However, there
is a FIXME at least in copyfrom_info_receiver() in libsvn_client/log.c,
stating that other callbacks may eventually be able to return
SVN_ERR_CEASE_INVOCATION as well.
Good idea, but I think that the callback should signal an error the same
way the Subversion functions do it - namely, by throwing
core.SubversionException. The wrapper would then translate the exception's
fields into an svn_error_t. It looks like tweaking
callback_exception_error is the most obvious way to do that. You don't
even have to special-case SVN_ERR_CEASE_INVOCATION, just copy whatever
code the exception had into the error.
It would also be great if you added a relevant test to the testsuite.
Thanks,
Roman.
