t4211 attempts to test multiple git-log -L ranges where one range is a
superset of the other, and falsely succeeds because its "expected"
output is incorrect.
Overlapping -L ranges handed to git-log are coalesced by
line-log.c:sort_and_merge_range_set() into a set of non-overlapping,
disjoint ranges. When one range is a subset of another,
sort_and_merge_range_set() should coalesce both ranges to the superset
range, but instead the coalesced range often is incorrectly truncated to
the end of the subset range. For example, ranges 2-8 and 3-4 are
coalesced incorrectly to 2-4.
One can observe this incorrect behavior with git-log -L using the test
repository created by t4211. The superset/subset ranges t4211 employs
are 4-$ and 8-12 (where $ represents end-of-file). The coalesced range
should be 4-$. Manually invoking git-log with the same ranges the test
employs, we see:
% git log -L 4:a.c simple |
awk '/^commit [0-9a-f]{40}/ { print substr($2,1,7) }'
4659538
100b61a
39b6eb2
a6eb826
f04fb20
de4c48a
% git log -L 8,12:a.c simple | awk ...
f04fb20
de4c48a
% git log -L 4:a.c -L 8,12:a.c simple | awk ...
a6eb826
f04fb20
de4c48a
This last output is incorrect. 8-12 is a subset of 4-$, hence the output
of the coalesced range should be the same as the 4-$ output shown first.
In fact, the above incorrect output is the truncated bogus range 4-12:
% git log -L 4,12:a.c simple | awk ...
a6eb826
f04fb20
de4c48a
Fix the test to correctly fail in the presence of the
sort_and_merge_range_set() coalescing bug. Do so by changing the
"expected" output to the commits mentioned in the 4-$ output above.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This tests a toy example of a history like
* Merge
| \
| * Modify foo
| |
* | Rename foo->bar
| /
* Create foo
Current log -L fails on this; we'll fix it in the next commit.
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Embarrassingly, the -M test did not actually invoke -M, and thus not
really test the feature.
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The existing code was too defensive, and would trigger the assert in
range_set_append() if the user gave overlapping ranges.
The intent was always to define overlapping ranges as just the union
of all of them, as evidenced by the call to sort_and_merge_range_set().
(Which was already used, unlike what the comment said.)
Fix by splitting out the meat of range_set_append() to a new _unsafe()
function that lacks the paranoia. sort_and_merge_range_set will fix
up the ranges, so we don't need the checks there.
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new syntax finds a funcname matching /pattern/, and then takes from there
up to (but not including) the next funcname. So you can say
git log -L:main:main.c
and it will dig up the main() function and show its line-log, provided
there are no other funcnames matching 'main'.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is a rewrite of much of Bo's work, mainly in an effort to split
it into smaller, easier to understand routines.
The algorithm is built around the struct range_set, which encodes a
series of line ranges as intervals [a,b). This is used in two
contexts:
* A set of lines we are tracking (which will change as we dig through
history).
* To encode diffs, as pairs of ranges.
The main routine is range_set_map_across_diff(). It processes the
diff between a commit C and some parent P. It determines which diff
hunks are relevant to the ranges tracked in C, and computes the new
ranges for P.
The algorithm is then simply to process history in topological order
from newest to oldest, computing ranges and (partial) diffs. At
branch points, we need to merge the ranges we are watching. We will
find that many commits do not affect the chosen ranges, and mark them
TREESAME (in addition to those already filtered by pathspec limiting).
Another pass of history simplification then gets rid of such commits.
This is wired as an extra filtering pass in the log machinery. This
currently only reduces code duplication, but should allow for other
simplifications and options to be used.
Finally, we hook a diff printer into the output chain. Ideally we
would wire directly into the diff logic, to optionally use features
like word diff. However, that will require some major reworking of
the diff chain, so we completely replace the output with our own diff
for now.
As this was a GSoC project, and has quite some history by now, many
people have helped. In no particular order, thanks go to
Jakub Narebski <jnareb@gmail.com>
Jens Lehmann <Jens.Lehmann@web.de>
Jonathan Nieder <jrnieder@gmail.com>
Junio C Hamano <gitster@pobox.com>
Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Will Palmer <wmpalmer@gmail.com>
Apologies to everyone I forgot.
Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
