Re: Assert IS_VALID_FORWARD_RANGE fails in merge_tests 125
From: Julian Foad <julianfoad_at_btopenworld.com>
Date: Thu, 29 Nov 2012 01:35:51 +0000 (GMT)
Paul Burba wrote:
> Julian Foad wrote:
>> I debugged this assertion failure and came up with this fix:
>> Fix issue #4132 "merge of replaced source asserts", fixing merge_tests 125.
>> * subversion/libsvn_client/merge.c
>> (find_gaps_in_merge_source_history): Fix an off-by-1 bug. Assert that the
>> function's result constitutes a valid non-empty range.
>> Index: subversion/libsvn_client/merge.c
>> --- subversion/libsvn_client/merge.c (revision 1414469)
>> +++ subversion/libsvn_client/merge.c (working copy)
>> @@ -4310,7 +4310,7 @@ find_gaps_in_merge_source_history(svn_re
>> /* Get SOURCE as mergeinfo. */
>> SVN_ERR(svn_client__get_history_as_mergeinfo(&implicit_src_mergeinfo, NULL,
>> - primary_src->rev, old_rev,
>> + primary_src->rev, old_rev + 1,
>> ctx, scratch_pool));
>> @@ -4384,6 +4384,9 @@ find_gaps_in_merge_source_history(svn_re
>> SVN_ERR_ASSERT(*gap_start == MIN(source->loc1->rev, source->loc2->rev)
>> || (*gap_start == SVN_INVALID_REVNUM
>> && *gap_end == SVN_INVALID_REVNUM));
>> + SVN_ERR_ASSERT(*gap_end > *gap_start
>> + || (*gap_start == SVN_INVALID_REVNUM
>> + && *gap_end == SVN_INVALID_REVNUM));
>> return SVN_NO_ERROR;
>> Trouble is, this fix makes merge_tests.py 100 fail.
> merge_tests.py 100 demonstrates the problem with what you propose
> Anyway, I hope that helps explain what is happening here.
Thanks for the detailed walk-through, Paul.
What I have found so far (I spent a bit more time on it today) is that the error is *much* earlier than here, right at the start of the merge: normalize_merge_sources_internal() comes up with the result (2,9).
Adding some debugging as in the attached 'merge-t-125-1.patch':
$ svn merge -r9:2 .../A A_COPY --dry-run ...
DBG: merge.c:6566: oldest 2, youngest 9
DBG: merge.c:6592: Location segments:
DBG: merge.c:6597: 0: 2-2 'A'
DBG: merge.c:6597: 1: 3-6 '(null)'
DBG: merge.c:6597: 2: 7-9 'A'
DBG: merge.c:6701: Resulting merge_source_ts:
DBG: merge.c:6706: 0: 9 '.../repositories/merge_tests-100/A'
DBG: merge.c:6707: 2 '.../repositories/merge_tests-100/A'
So that's where I'm at.
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