When line-level log is invoked with more than one disjoint line range
in the same file, and one of the commits happens to change that file
such that one diff range modifies more than one line range, then
changes to all modified line ranges should be shown, but only the
changes in the first modified line range are:
$ git log --oneline -p
80ca903 (HEAD -> master) Initial
diff --git a/file b/file
new file mode 100644
index 0000000..00935f1
--- /dev/null
+++ b/file
@@ -0,0 +1,10 @@
+Line 1
+Line 2
+Line 3
+Line 4
+Line 5
+Line 6
+Line 7
+Line 8
+Line 9
+Line 10
$ git log --oneline -L1,2:file -L4,5:file -L7,8:file
80ca903 (HEAD -> master) Initial
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +1,2 @@
+Line 1
+Line 2
The line-log-specific diff printer is already clever enough to handle
the case when one line range covers multiple diff ranges, but the
possibility of one diff range touching multiple disjoint line ranges
was apparently overlooked.
Add the necessary condition to dump_diff_hacky_one() to handle this case
as well, and show all modified line ranges:
$ git log --oneline -L1,2:file -L4,5:file -L7,8:file
0f9a5b4 (HEAD -> master) Initial
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +1,2 @@
+Line 1
+Line 2
@@ -0,0 +4,2 @@
+Line 4
+Line 5
@@ -0,0 +7,2 @@
+Line 7
+Line 8
This bug was already present in the initial line-log implementation
added in 2da1d1f6f (Implement line-history search (git log -L),
2013-03-28). Interestingly, that commit already contained a canned
test case covering a similar scenario:
"-L '/long f/',/^}/:a.c -L /main/,/^}/:a.c simple"
This test case looks for two line ranges in the same file, and both
trace back disjointly to the test repository's inital commit,
therefore changes to both line ranges should have been shown for the
initial commit, but only changes for the first line range are shown.
So this test case should have failed from the very beginning, but it
never did, because, unfortunately, the canned expected result is
incorrect, as it doesn't include changes for the second line range.
A similar test with a similarly incorrect canned expected result was
added later in 209618860c (log -L: fix overlapping input ranges,
2013-04-05).
Correct these two canned expected results to contain the changes for
the second line range for the initial commit as well.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When line-level log is invoked with more than one disjoint line range
in the same file, and one of the commits happens to change that file
such that:
- the last line of a line range R(n) immediately preceeds the first line
modified or added by a hunk H, and
- subtracting the number of lines added by hunk H from the start and
end of the subsequent line range R(n+1) would result in a range
overlapping with line range R(n),
then git aborts with an assertion error, because those overlapping
line ranges violate the invariants:
$ git log --oneline -p
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
index 572d5d9..00935f1 100644
--- a/file
+++ b/file
@@ -3,3 +3,8 @@ Line 2
Line 3
Line 4
Line 5
+Line 6
+Line 7
+Line 8
+Line 9
+Line 10
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
new file mode 100644
index 0000000..572d5d9
--- /dev/null
+++ b/file
@@ -0,0 +1,5 @@
+Line 1
+Line 2
+Line 3
+Line 4
+Line 5
$ git log --oneline -L3,5:file -L7,8:file
git: line-log.c:73: range_set_append: Assertion `rs->nr == 0 || rs->ranges[rs->nr-1].end <= a' failed.
Aborted (core dumped)
The line-log machinery encodes line and diff ranges internally as
[start, end) pairs, i.e. include 'start' but exclude 'end', and line
numbering starts at 0 (as opposed to the -LX,Y option, where it starts
at 1, IOW the parameter -L3,5 is represented internally as { start =
2, end = 5 }).
The reason for this assertion error and some related issues is that
there are a couple of places where 'end' is mistakenly considered to
be part of the range:
- When a commit modifies an interesting path, the line-log machinery
first checks which diff range (i.e. hunk) modify any line ranges.
This is done in diff_ranges_filter_touched(), where the outer loop
iterates over the diff ranges, and in each iteration the inner
loop advances the line ranges supposedly until the current line
range ends at or after the current diff range starts, and then the
current diff and line ranges are checked for overlap.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10) starts, so the inner loop
should advance, and then the second line range [6, 8) and the diff
range should be checked for overlap.
Unfortunately, the condition of the inner loop mistakenly
considers 'end' as part of the line range, and, seeing the diff
range starting at 5 and the line range ending at 5, it doesn't
skip the first range. Consequently, the diff range and the first
line range are checked for overlap, and after that the outer loop
runs out of diff ranges, and then the processing goes on in the
false belief that this commit didn't touch any of the interesting
line ranges.
The line-log machinery later shifts the line ranges to account for
any added/removed lines in the diff ranges preceeding each line
range. This leaves the first line range intact, but attempts to
shift the second line range [6, 8) by 5 lines towards the
beginning of the file, resulting in [1, 3), triggering the
assertion error, because the two overlapping line ranges violate
the invariants.
Fix that loop condition in diff_ranges_filter_touched() to not
treat 'end' as part of the line range.
- With the above fix the assertion error is gone... but, alas, we
now get stuck in an endless loop!
This happens in range_set_difference(), where a couple of nested
loops iterate over the line and diff ranges, and a condition is
supposed to break the middle loop when the current line range ends
before the current diff range, so processing could continue with
the next line range.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10) starts, so this condition
should trigger and break the middle loop.
Unfortunately, just like in the case of the assertion error, this
conditions mistakenly considers 'end' as part of the line range,
and, seeing the line range ending at 5 and the diff range starting
at 5, it doesn't break the loop, which will then go on and on.
Fix this condition in range_set_difference() to not treat 'end' as
part of the line range.
- With the above fix the endless loop is gone... but, alas, the
output is now wrong, as it shows both line ranges for HEAD, even
though the first line range is not modified by that commit:
$ git log --oneline -L3,5:file -L7,8:file
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
--- a/file
+++ b/file
@@ -3,3 +3,3 @@
Line 3
Line 4
Line 5
@@ -6,0 +7,2 @@
+Line 7
+Line 8
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +3,3 @@
+Line 3
+Line 4
+Line 5
In dump_diff_hacky_one() a couple of nested loops are responsible
for finding and printing the modified line ranges: the big outer
loop iterates over all line ranges, and the first inner loop skips
over the diff ranges that end before the start of the current line
range. This is followed by a condition checking whether the
current diff range starts after the end of the current line range,
which, when fulfilled, continues and advances the outer loop to
the next line range.
For HEAD in the above example the first line range [2, 5) ends
just before the diff range [5, 10), so this condition should
trigger, and the outer loop should advance to the second line
range.
Unfortunately, just like in the previous cases, this condition
mistakenly considers 'end' as part of the line range, and, seeing
the first line range ending at 5 and the diff range starting at 5,
it doesn't continue to advance the outher loop, but goes on to
show the (unmodified) first line range.
Fix this condition to not treat 'end' as part of the line range,
just like in the previous cases.
After all this the command in the above example finally finishes and
produces the right output:
$ git log --oneline -L3,5:file -L7,8:file
73e4e2f (HEAD -> master) Add lines 6 7 8 9 10
diff --git a/file b/file
--- a/file
+++ b/file
@@ -6,0 +7,2 @@
+Line 7
+Line 8
66e3561 Add lines 1 2 3 4 5
diff --git a/file b/file
--- /dev/null
+++ b/file
@@ -0,0 +3,3 @@
+Line 3
+Line 4
+Line 5
Add a canned test similar to the above example, with the line ranges
adjusted to the test repository's history.
Reported-by: Evgeni Chasnovski <evgeni.chasnovski@gmail.com>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Carefully excluding t4013 and t4015, which see independent development
elsewhere at the time of writing, we use `main` as the default branch
name in t4*. This trick was performed via
$ (cd t &&
sed -i -e 's/master/main/g' -e 's/MASTER/MAIN/g' \
-e 's/Master/Main/g' -- t4*.sh t4211/*.export &&
git checkout HEAD -- t4013\*)
This allows us to define `GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main`
for those tests.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There are already files containing example output for SHA-1. Add test
files providing example output for SHA-256 as well and adjust the test
to look up the appropriate ones based on the algorithm in use.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In preparation for adding SHA-256 support to this test, let's move the
SHA-1-specific expected output into a directory called "sha1". This
will allow us to add a similar directory for SHA-256 as well.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
