When --count is used with --cherry-mark, omit the patch equivalent
commits from the count for left and right commits and print the count of
equivalent commits separately.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* mg/rev-list-n-parents:
tests: avoid nonportable {foo,bar} glob
rev-list --min-parents,--max-parents: doc, test and completion
revision.c: introduce --min-parents and --max-parents options
t6009: use test_commit() from test-lib.sh
Introduce --min-parents and --max-parents options which limit the
revisions to those commits which have at least (or at most) that many
commits, where negative arguments for --max-parents= denote infinity
(i.e. no upper limit).
In particular:
--max-parents=1 is the same as --no-merges;
--min-parents=2 is the same as --merges;
--max-parents=0 shows only roots; and
--min-parents=3 shows only octopus merges
Using --min-parents=n and --max-parents=m with n>m gives you what you ask
for (i.e. nothing) for obvious reasons, just like when you give --merges
(show only merge commits) and --no-merges (show only non-merge commits) at
the same time.
Also, introduce --no-min-parents and --no-max-parents to do the obvious
thing for convenience.
We compute the number of parents only when we limit by that, so there
is no performance impact when there are no limiters.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* mg/rev-list-one-side-only:
git-log: put space after commit mark
t6007: test rev-list --cherry
log --cherry: a synonym
rev-list: documentation and test for --cherry-mark
revision.c: introduce --cherry-mark
rev-list/log: factor out revision mark generation
rev-list: --left/right-only are mutually exclusive
rev-list: documentation and test for --left/right-only
t6007: Make sure we test --cherry-pick
revlist.c: introduce --left/right-only for unsymmetric picking
Currently, commit marks (left, right, boundary, cherry) are output right
before the commit sha1, which makes it difficult to copy sha1s. Sample
output for "git log --oneline --cherry":
=049c269 t6007: test rev-list --cherry
Change this to
= 049c269 t6007: test rev-list --cherry
which matches exactly the current output of "git log --graph".
Leave "git rev-list" output as is (no space) so that they do not break.
Adjust "git-svn" which uses "git log --pretty=raw --boundary".
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
for marking those commits which "--cherry-pick" would drop.
The marker for those commits is '=' because '-' denotes a boundary
commit already, even though 'git cherry' uses it.
Nonequivalent commits are denoted '+' unless '--left-right' is used.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, we have identical code for generating revision marks ('<',
'>', '-') in 5 places.
Factor out the code to a single function get_revision_mark() for easier
maintenance and extensibility.
Note that the check for !!revs in graph.c (which gets removed
effectively by this patch) is superfluous.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The existing "--cherry-pick" does not work with unsymmetric ranges
(A..B) for obvious reasons.
Introduce "--left-only" and "--right-only" which limit the output to
commits on the respective sides of a symmetric range (i.e. only "<"
resp. ">" commits as per "--left-right").
This is especially useful for things like
git log --cherry-pick --right-only @{u}...
which is much more flexible (and descriptive) than
git cherry @{u} | sed -ne 's/^+ //p'
and potentially more useful than
git log --cherry-pick @{u}...
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
By passing the path to a submodule in opt->submodule, the function can
be used to walk history in the named submodule repository, instead of
the toplevel repository.
Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a --count option that, instead of actually listing the commits,
merely counts them.
This is mostly geared towards script use, and to this end it acts
specially when used with --left-right: it outputs the left and right
counts separately. Previously, scripts would have to run a shell loop
or small inline script over to achieve the same. (Without
--left-right, a simple |wc -l does the job.)
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"rev-list A..H" computes the set of commits that are ancestors of H, but
excludes the ones that are ancestors of A. This is useful to see what
happened to the history leading to H since A, in the sense that "what does
H have that did not exist in A" (e.g. when you have a choice to update to
H from A).
x---x---A---B---C <-- topic
/ \
x---x---x---o---o---o---o---M---D---E---F---G <-- dev
/ \
x---o---o---o---o---o---o---o---o---o---o---o---N---H <-- master
The result in the above example would be the commits marked with caps
letters (except for A itself, of course), and the ones marked with 'o'.
When you want to find out what commits in H are contaminated with the bug
introduced by A and need fixing, however, you might want to view only the
subset of "A..B" that are actually descendants of A, i.e. excluding the
ones marked with 'o'. Introduce a new option --ancestry-path to compute
this set with "rev-list --ancestry-path A..B".
Note that in practice, you would build a fix immediately on top of A and
"git branch --contains A" will give the names of branches that you would
need to merge the fix into (i.e. topic, dev and master), so this may not
be worth paying the extra cost of postprocessing.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* tr/notes-display:
git-notes(1): add a section about the meaning of history
notes: track whether notes_trees were changed at all
notes: add shorthand --ref to override GIT_NOTES_REF
commit --amend: copy notes to the new commit
rebase: support automatic notes copying
notes: implement helpers needed for note copying during rewrite
notes: implement 'git notes copy --stdin'
rebase -i: invoke post-rewrite hook
rebase: invoke post-rewrite hook
commit --amend: invoke post-rewrite hook
Documentation: document post-rewrite hook
Support showing notes from more than one notes tree
test-lib: unset GIT_NOTES_REF to stop it from influencing tests
Conflicts:
git-am.sh
refs.c
With this patch, you can set notes.displayRef to a glob that points at
your favourite notes refs, e.g.,
[notes]
displayRef = refs/notes/*
Then git-log and friends will show notes from all trees.
Thanks to Junio C Hamano for lots of feedback, which greatly
influenced the design of the entire series and this commit in
particular.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Acked-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Traditionally, "show" defaulted to "show --cc" (dense combined patch), but
asking for combined patch with "show -c" didn't turn the patch output
format on; the placement of this logic in setup_revisions() dates back to
cd2bdc5 (Common option parsing for "git log --diff" and friends,
2006-04-14).
This unfortunately cannot be done as a trivial change of "if dense
combined is asked, default to patch format" done in setup_revisions() to
"if any combined is asked, default to patch format", as "diff-tree -c"
needs to default to raw, while "diff-tree --cc" needs to default to patch,
and they share the codepath. These command specific defaults are now
handled in the new "tweak" callback that can be customized by individual
command implementations.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
So far the last parameter to setup_revisions() was to specify the default
ref when the command line did not give any (typically "HEAD"). This changes
it to take a pointer to a structure so that we can add other information without
touching too many codepaths in later patches.
There is no functionality change.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Giving "Notes" information in the default output format of "log" and
"show" is a sensible progress (the user has asked for it by having the
notes), but for some commands (e.g. "format-patch") spewing notes into the
formatted commit log message without being asked is too aggressive.
Enable notes output only for "log", "show", "whatchanged" by default and
only when the user didn't ask any specific --pretty/--format from the
command line; users can explicitly override this default with --show-notes
and --no-notes option.
Parts of tests are taken from Jeff King's fix.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/log-stdin:
Add trivial tests for --stdin option to log family
Make --stdin option to "log" family read also pathspecs
setup_revisions(): do not call get_pathspec() too early
Teach --stdin option to "log" family
read_revision_from_stdin(): use strbuf
Conflicts:
revision.c
Move the logic to read revs from standard input that rev-list knows about
from it to revision machinery, so that all the users of setup_revisions()
can feed the list of revs from the standard input when "--stdin" is used
on the command line.
Allow some users of the revision machinery that want different semantics
from the "--stdin" option to disable it by setting an option in the
rev_info structure.
This also cleans up the kludge made to bundle.c via cut and paste.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
I personally use "git bisect visualize" all the time when I bisect, but it
turns out that that is not a very flexible model. Sometimes I want to do
bisection based on all commits (no pathname limiting), but then visualize
the current bisection tree with just a few pathnames because I _suspect_
those pathnames are involved in the problem but am not totally sure about
them.
And at other times, I want to use other revision parsing logic, none of
which is available with "git bisect visualize".
So this adds "--bisect" as a revision parsing argument, and as a result it
just works with all the normal logging tools. So now I can just do
gitk --bisect --simplify-by-decoration filename-here
etc.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we show a reflog, we have two ways of naming the entry:
by sequence number (e.g., HEAD@{0}) or by date (e.g.,
HEAD@{10 minutes ago}). There is no explicit option to set
one or the other, but we guess based on whether or not the
user has provided us with a date format, showing them the
date version if they have done so, and the sequence number
otherwise.
This usually made sense if the use did something like "git
log -g --date=relative". However, it didn't make much sense
if the user set the date format using the log.date config
variable; in that case, all of their reflogs would end up as
dates.
This patch records the source of the date format and only
triggers the date-based view if --date= was given on the
command line.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Previously, graph_is_interesting() did not behave quite the same way as
the code in get_revision(). As a result, it would sometimes think
commits were uninteresting, even though get_revision() would return
them. This resulted in incorrect lines in the graph output.
This change creates a get_commit_action() function, which
graph_is_interesting() and simplify_commit() both now use to determine
if a commit will be shown. It is identical to the old simplify_commit()
behavior, except that it never calls rewrite_parents().
This problem was reported by Santi Béjar. The following command
would exhibit the problem before, but now works correctly:
git log --graph --simplify-by-decoration --oneline v1.6.3.3
Previously git graph did not display the output for this command
correctly between f29ac4f and 66996ec, among other places.
Signed-off-by: Adam Simpkins <simpkins@facebook.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit de435ac0 changed the behavior of --decorate from printing the
full ref (e.g., "refs/heads/master") to a shorter, more human-readable
version (e.g., just "master"). While this is nice for human readers,
external tools using the output from "git log" may prefer the full
version.
This patch introduces an extension to --decorate to allow the caller to
specify either the short or the full versions.
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
I do various statistics on git, and one of the things I look at is merges,
because they are often interesting events to count ("how many merges vs
how much 'real development'" kind of statistics). And you can do it with
some fairly straightforward scripting, ie
git rev-list --parents HEAD |
grep ' .* ' |
git diff-tree --always -s --pretty=oneline --stdin |
less -S
will do it.
But I finally got irritated with the fact that we can skip merges with
'--no-merges', but we can't do the trivial reverse operation.
So this just adds a '--merges' flag that _only_ shows merges. Now you can
do the above with just a
git log --merges --pretty=oneline
which is a lot simpler. It also means that we automatically get a lot of
statistics for free, eg
git shortlog -ns --merges
does exactly what you'd want it to do.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This simplifies the logic of rev_compare_tree() by removing a special
case.
It does so by turning the special case of finding a diff to be "all new
files" into a more generic case of "all new" vs "all removed" vs "mixed
changes", so now the code is actually more powerful and more generic, and
the added symmetry actually makes it simpler too.
This makes no changes to any existing behavior, but apart from the
simplification it does make it possible to some day care about whether all
changes were just deletions if we want to. Which we may well want to for
merge handling.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* lt/pack-object-memuse:
show_object(): push path_name() call further down
process_{tree,blob}: show objects without buffering
Conflicts:
builtin-pack-objects.c
builtin-rev-list.c
list-objects.c
list-objects.h
upload-pack.c
In particular, pushing the "path_name()" call _into_ the show() function
would seem to allow
- more clarity into who "owns" the name (ie now when we free the name in
the show_object callback, it's because we generated it ourselves by
calling path_name())
- not calling path_name() at all, either because we don't care about the
name in the first place, or because we are actually happy walking the
linked list of "struct name_path *" and the last component.
Now, I didn't do that latter optimization, because it would require some
more coding, but especially looking at "builtin-pack-objects.c", we really
don't even want the whole pathname, we really would be better off with the
list of path components.
Why? We use that name for two things:
- add_preferred_base_object(), which actually _wants_ to traverse the
path, and now does it by looking for '/' characters!
- for 'name_hash()', which only cares about the last 16 characters of a
name, so again, generating the full name seems to be just unnecessary
work.
Anyway, so I didn't look any closer at those things, but it did convince
me that the "show_object()" calling convention was crazy, and we're
actually better off doing _less_ in list-objects.c, and giving people
access to the internal data structures so that they can decide whether
they want to generate a path-name or not.
This patch does that, and then for people who did use the name (even if
they might do something more clever in the future), it just does the
straightforward "name = path_name(path, component); .. free(name);" thing.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Here's a less trivial thing, and slightly more dubious one.
I was looking at that "struct object_array objects", and wondering why we
do that. I have honestly totally forgotten. Why not just call the "show()"
function as we encounter the objects? Rather than add the objects to the
object_array, and then at the very end going through the array and doing a
'show' on all, just do things more incrementally.
Now, there are possible downsides to this:
- the "buffer using object_array" _can_ in theory result in at least
better I-cache usage (two tight loops rather than one more spread out
one). I don't think this is a real issue, but in theory..
- this _does_ change the order of the objects printed. Instead of doing a
"process_tree(revs, commit->tree, &objects, NULL, "");" in the loop
over the commits (which puts all the root trees _first_ in the object
list, this patch just adds them to the list of pending objects, and
then we'll traverse them in that order (and thus show each root tree
object together with the objects we discover under it)
I _think_ the new ordering actually makes more sense, but the object
ordering is actually a subtle thing when it comes to packing
efficiency, so any change in order is going to have implications for
packing. Good or bad, I dunno.
- There may be some reason why we did it that odd way with the object
array, that I have simply forgotten.
Anyway, now that we don't buffer up the objects before showing them
that may actually result in lower memory usage during that whole
traverse_commit_list() phase.
This is seriously not very deeply tested. It makes sense to me, it seems
to pass all the tests, it looks ok, but...
Does anybody remember why we did that "object_array" thing? It used to be
an "object_list" a long long time ago, but got changed into the array due
to better memory usage patterns (those linked lists of obejcts are
horrible from a memory allocation standpoint). But I wonder why we didn't
do this back then. Maybe there's a reason for it.
Or maybe there _used_ to be a reason, and no longer is.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* sb/format-patch-patchname:
format_sanitized_subject: Don't trim past initial length of strbuf
log-tree: fix patch filename computation in "git format-patch"
format-patch: --numbered-files and --stdout aren't mutually exclusive
format-patch: --attach/inline uses filename instead of SHA1
format-patch: move get_patch_filename() into log-tree
format-patch: pass a commit to reopen_stdout()
format-patch: construct patch filename in one function
pretty.c: add %f format specifier to format_commit_message()
* jc/maint-1.6.0-keep-pack:
pack-objects: don't loosen objects available in alternate or kept packs
t7700: demonstrate repack flaw which may loosen objects unnecessarily
Remove --kept-pack-only option and associated infrastructure
pack-objects: only repack or loosen objects residing in "local" packs
git-repack.sh: don't use --kept-pack-only option to pack-objects
t7700-repack: add two new tests demonstrating repacking flaws
Conflicts:
t/t7700-repack.sh
Currently when format-patch is used with --attach or --inline the patch
attachment has the SHA1 of the commit for its filename. This replaces
the SHA1 with the filename used by format-patch when outputting to
files.
Fix tests relying on the SHA1 output and add a test showing how the
--suffix option affects the attachment filename output.
Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This option to pack-objects/rev-list was created to improve the -A and -a
options of repack. It was found to be lacking in that it did not provide
the ability to differentiate between local and non-local kept packs, and
found to be unnecessary since objects residing in local kept packs can be
filtered out by the --honor-pack-keep option.
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/maint-1.6.0-keep-pack:
is_kept_pack(): final clean-up
Simplify is_kept_pack()
Consolidate ignore_packed logic more
has_sha1_kept_pack(): take "struct rev_info"
has_sha1_pack(): refactor "pretend these packs do not exist" interface
git-repack: resist stray environment variable
Now is_kept_pack() is just a member lookup into a structure, we can write
it as such.
Also rewrite the sole caller of has_sha1_kept_pack() to switch on the
criteria the callee uses (namely, revs->kept_pack_only) between calling
has_sha1_kept_pack() and has_sha1_pack(), so that these two callees do not
have to take a pointer to struct rev_info as an argument.
This removes the header file dependency issue temporarily introduced by
the earlier commit, so we revert changes associated to that as well.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This removes --unpacked=<packfile> parameter from the revision parser, and
rewrites its use in git-repack to pass a single --kept-pack-only option
instead.
The new --kept-pack-only option means just that. When this option is
given, is_kept_pack() that used to say "not on the --unpacked=<packfile>
list" now says "the packfile has corresponding .keep file".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This refactors three loops that check if a given packfile is on the
ignore_packed list into a function is_kept_pack(). The function returns
false for a pack on the list, and true for a pack not on the list, because
this list is solely used by "git repack" to pass list of packfiles that do
not have corresponding .keep files, i.e. a packfile not on the list is
"kept".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Its "ignore_packed" parameter always comes from struct rev_info. This
patch makes the function take a pointer to the surrounding structure, so
that the refactoring in the next patch becomes easier to review.
There is an unfortunate header file dependency and the easiest workaround
is to temporarily move the function declaration from cache.h to
revision.h; this will be moved back to cache.h once the function loses
this "ignore_packed" parameter altogether in the later part of the
series.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, format-patch can only track a single reference (the
In-Reply-To:) for each mail. To ensure proper threading, we should
list all known references for every mail.
Change the rev_info.ref_message_id field to a string_list, so that we
can append references at will, and change the output formatting
routines to print all of them in the References: header. The last
entry in the list is implicitly assumed to be the In-Reply-To:, which
gives output consistent with RFC 2822:
The "References:" field will contain the contents of the parent's
"References:" field (if any) followed by the contents of the
parent's "Message-ID:" field (if any).
Note that this is just preparatory work; nothing uses it yet, so all
"References:" fields in the output are still only one deep.
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
With this, you can simplify history not by the contents of the tree, but
whether a commit has been named (ie it's referred to by some branch or
tag) or not.
This makes it possible to see the relationship between different named
commits, without actually seeing any of the details.
When used with pathspec, you would get the usual view that is limited to
the commits that change the contents of the tree plus commits that are
named.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We will want to add decorations without necessarily showing them, so add
an explicit revisions info flag as to whether we're showing decorations
or not.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We already support decorating commits by tags or branches that point to
them, but especially when we are looking at multiple branches together,
we sometimes want to see _how_ we reached a particular commit.
We can abuse the '->util' field in the commit to keep track of that as
we walk the commit lists, and get a reasonably useful view into which
branch or tag first reaches that commit.
Of course, if the commit is reachable through multiple sources (which is
common), our particular choice of "first" reachable is entirely random
and depends on the particular path we happened to follow.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* tr/filter-branch:
revision --simplify-merges: make it a no-op without pathspec
revision --simplify-merges: do not leave commits unprocessed
revision --simplify-merges: use decoration instead of commit->util field
Documentation: rev-list-options: move --simplify-merges documentation
filter-branch: use --simplify-merges
filter-branch: fix ref rewriting with --subdirectory-filter
filter-branch: Extend test to show rewriting bug
Topo-sort before --simplify-merges
revision traversal: show full history with merge simplification
revision.c: whitespace fix
--reverse did not interact well with --parents, as the included test
case shows: in a history like
A--B.
\ \
`C--M--D
the command
git rev-list --reverse --parents --full-history HEAD
erroneously lists D as having no parents at all. (Without --reverse,
it correctly lists M.)
This is caused by the machinery driving --reverse: it first grabs all
commits through the normal routines, then runs them through the same
routines again, effectively simplifying them twice.
Fix this by moving the --reverse one level up, into get_revision().
This way we can cleanly grab all commits via the normal calls, then
just pop them off the list one by one without interfering with
get_revision_internal().
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This has been broken in v1.6.0 due to the reorganization of
the revision option parsing code. The "-i" is completely
ignored, but works fine in "git log --grep -i".
What happens is that the code for "-i" looks for
revs->grep_filter; if it is NULL, we do nothing, since there
are no grep filters. But that is obviously not correct,
since we want it to influence the later --grep option. Doing
it the other way around works, since "-i" just impacts the
existing grep_filter option.
Instead, we now always initialize the grep_filter member and
just fill in options and patterns as we get them. This means
that we can no longer check grep_filter for NULL, but
instead must check the pattern list to see if we have any
actual patterns.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The variable show_early_output is defined in revision.c and should be
declared extern in revision.h so that the linker does not complain
about multiply defined variables.
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The users of revision walking machinery may want to use the util pointer
for their own use. Use decoration to hold the data needed during merge
simplification instead.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --full-history traversal keeps all merges in addition to non-merge
commits that touch paths in the given pathspec. This is useful to view
both sides of a merge in a topology like this:
A---M---o
/ /
---O---B
even when A and B makes identical change to the given paths. The revision
traversal without --full-history aims to come up with the simplest history
to explain the final state of the tree, and one of the side branches can
be pruned away.
The behaviour to keep all merges however is inconvenient if neither A nor
B touches the paths we are interested in. --full-history reduces the
topology to:
---O---M---o
in such a case, without removing M.
This adds a post processing phase on top of --full-history traversal to
remove needless merges from the resulting history.
The idea is to compute, for each commit in the "full history" result set,
the commit that should replace it in the simplified history. The commit
to replace it in the final history is determined as follows:
* In any case, we first figure out the replacement commits of parents of
the commit we are looking at. The commit we are looking at is
rewritten as if the replacement commits of its original parents are its
parents. While doing so, we reduce the redundant parents from the
rewritten parent list by not just removing the identical ones, but also
removing a parent that is an ancestor of another parent.
* After the above parent simplification, if the commit is a root commit,
an UNINTERESTING commit, a merge commit, or modifies the paths we are
interested in, then the replacement commit of the commit is itself. In
other words, such a commit is not dropped from the final result.
The first point above essentially means that the history is rewritten in
the bottom up direction. We can rewrite the parent list of a commit only
after we know how all of its parents are rewritten. This means that the
processing needs to happen on the full history (i.e. after limit_list()).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
