git-commit-vandalism/Documentation/git-rev-list.txt

152 lines
4.9 KiB
Plaintext
Raw Normal View History

git-rev-list(1)
===============
NAME
----
git-rev-list - Lists commit objects in reverse chronological order
SYNOPSIS
--------
[verse]
'git-rev-list' [ \--max-count=number ]
[ \--max-age=timestamp ]
[ \--min-age=timestamp ]
[ \--sparse ]
[ \--no-merges ]
[ \--all ]
[ [ \--merge-order [ \--show-breaks ] ] | [ \--topo-order ] ]
[ \--parents ]
[ \--objects [ \--unpacked ] ]
[ \--pretty | \--header ]
[ \--bisect ]
<commit>... [ \-- <paths>... ]
DESCRIPTION
-----------
Lists commit objects in reverse chronological order starting at the
given commit(s), taking ancestry relationship into account. This is
useful to produce human-readable log output.
Commits which are stated with a preceding '{caret}' cause listing to stop at
that point. Their parents are implied. "git-rev-list foo bar {caret}baz" thus
means "list all the commits which are included in 'foo' and 'bar', but
not in 'baz'".
A special notation <commit1>..<commit2> can be used as a
short-hand for {caret}<commit1> <commit2>.
OPTIONS
-------
--pretty::
Print the contents of the commit changesets in human-readable form.
--header::
Print the contents of the commit in raw-format; each
record is separated with a NUL character.
--objects::
Print the object IDs of any object referenced by the listed commits.
'git-rev-list --objects foo ^bar' thus means "send me all object IDs
which I need to download if I have the commit object 'bar', but
not 'foo'".
--unpacked::
Only useful with `--objects`; print the object IDs that
are not in packs.
--bisect::
Limit output to the one commit object which is roughly halfway
between the included and excluded commits. Thus, if 'git-rev-list
--bisect foo ^bar ^baz' outputs 'midpoint', the output
of 'git-rev-list foo ^midpoint' and 'git-rev-list midpoint
^bar ^baz' would be of roughly the same length. Finding the change
which introduces a regression is thus reduced to a binary search:
repeatedly generate and test new 'midpoint's until the commit chain
is of length one.
--max-count::
Limit the number of commits output.
--max-age=timestamp, --min-age=timestamp::
Limit the commits output to specified time range.
--sparse::
When optional paths are given, the command outputs only
the commits that changes at least one of them, and also
ignores merges that do not touch the given paths. This
flag makes the command output all eligible commits
(still subject to count and age limitation), but apply
merge simplification nevertheless.
--all::
Pretend as if all the refs in `$GIT_DIR/refs/` are
listed on the command line as <commit>.
--topo-order::
By default, the commits are shown in reverse
chronological order. This option makes them appear in
topological order (i.e. descendant commits are shown
before their parents).
--merge-order::
When specified the commit history is decomposed into a unique
sequence of minimal, non-linear epochs and maximal, linear epochs.
Non-linear epochs are then linearised by sorting them into merge
order, which is described below.
+
Maximal, linear epochs correspond to periods of sequential development.
Minimal, non-linear epochs correspond to periods of divergent development
followed by a converging merge. The theory of epochs is described in more
detail at
link:http://blackcubes.dyndns.org/epoch/[http://blackcubes.dyndns.org/epoch/].
+
The merge order for a non-linear epoch is defined as a linearisation for which
the following invariants are true:
+
1. if a commit P is reachable from commit N, commit P sorts after commit N
in the linearised list.
2. if Pi and Pj are any two parents of a merge M (with i < j), then any
commit N, such that N is reachable from Pj but not reachable from Pi,
sorts before all commits reachable from Pi.
+
Invariant 1 states that later commits appear before earlier commits they are
derived from.
+
Invariant 2 states that commits unique to "later" parents in a merge, appear
before all commits from "earlier" parents of a merge.
--show-breaks::
Each item of the list is output with a 2-character prefix consisting
of one of: (|), (^), (=) followed by a space.
+
Commits marked with (=) represent the boundaries of minimal, non-linear epochs
and correspond either to the start of a period of divergent development or to
the end of such a period.
+
Commits marked with (|) are direct parents of commits immediately preceding
the marked commit in the list.
+
Commits marked with (^) are not parents of the immediately preceding commit.
These "breaks" represent necessary discontinuities implied by trying to
represent an arbitrary DAG in a linear form.
+
`--show-breaks` is only valid if `--merge-order` is also specified.
Author
------
Written by Linus Torvalds <torvalds@osdl.org>
[PATCH] Modify git-rev-list to linearise the commit history in merge order. This patch linearises the GIT commit history graph into merge order which is defined by invariants specified in Documentation/git-rev-list.txt. The linearisation produced by this patch is superior in an objective sense to that produced by the existing git-rev-list implementation in that the linearisation produced is guaranteed to have the minimum number of discontinuities, where a discontinuity is defined as an adjacent pair of commits in the output list which are not related in a direct child-parent relationship. With this patch a graph like this: a4 --- | \ \ | b4 | |/ | | a3 | | | | | a2 | | | | c3 | | | | | c2 | b3 | | | /| | b2 | | | c1 | | / | b1 a1 | | | a0 | | / root Sorts like this: = a4 | c3 | c2 | c1 ^ b4 | b3 | b2 | b1 ^ a3 | a2 | a1 | a0 = root Instead of this: = a4 | c3 ^ b4 | a3 ^ c2 ^ b3 ^ a2 ^ b2 ^ c1 ^ a1 ^ b1 ^ a0 = root A test script, t/t6000-rev-list.sh, includes a test which demonstrates that the linearisation produced by --merge-order has less discontinuities than the linearisation produced by git-rev-list without the --merge-order flag specified. To see this, do the following: cd t ./t6000-rev-list.sh cd trash cat actual-default-order cat actual-merge-order The existing behaviour of git-rev-list is preserved, by default. To obtain the modified behaviour, specify --merge-order or --merge-order --show-breaks on the command line. This version of the patch has been tested on the git repository and also on the linux-2.6 repository and has reasonable performance on both - ~50-100% slower than the original algorithm. This version of the patch has incorporated a functional equivalent of the Linus' output limiting algorithm into the merge-order algorithm itself. This operates per the notes associated with Linus' commit 337cb3fb8da45f10fe9a0c3cf571600f55ead2ce. This version has incorporated Linus' feedback regarding proposed changes to rev-list.c. (see: [PATCH] Factor out filtering in rev-list.c) This version has improved the way sort_first_epoch marks commits as uninteresting. For more details about this change, refer to Documentation/git-rev-list.txt and http://blackcubes.dyndns.org/epoch/. Signed-off-by: Jon Seymour <jon.seymour@gmail.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-06 17:39:40 +02:00
Original *--merge-order* logic by Jon Seymour <jon.seymour@gmail.com>
Documentation
--------------
Documentation by David Greaves, Junio C Hamano and the git-list <git@vger.kernel.org>.
GIT
---
Part of the gitlink:git[7] suite