The `rebase` family of Git commands avoid applying patches that were
already integrated upstream. They do that by using the revision walking
option that computes the patch IDs of the two sides of the rebase
(local-only patches vs upstream-only ones) and skipping those local
patches whose patch ID matches one of the upstream ones.
In many cases, this causes unnecessary churn, as already the set of
paths touched by a given commit would suffice to determine that an
upstream patch has no local equivalent.
This hurts performance in particular when there are a lot of upstream
patches, and/or large ones.
Therefore, let's introduce the concept of a "diff-header-only" patch ID,
compare those first, and only evaluate the "full" patch ID lazily.
Please note that in contrast to the "full" patch IDs, those
"diff-header-only" patch IDs are prone to collide with one another, as
adjacent commits frequently touch the very same files. Hence we now
have to be careful to allow multiple hash entries with the same hash.
We accomplish that by using the hashmap_add() function that does not even
test for hash collisions. This also allows us to evaluate the full patch ID
lazily, i.e. only when we found commits with matching diff-header-only
patch IDs.
We add a performance test that demonstrates ~1-6% improvement. In
practice this will depend on various factors such as how many upstream
changes and how big those changes are along with whether file system
caches are cold or warm. As Git's test suite has no way of catching
performance regressions, we also add a regression test that verifies
that the full patch ID computation is skipped when the diff-header-only
computation suffices.
Signed-off-by: Kevin Willford <kcwillford@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This will allow a diff patch id to be created using only the header data
so that the contents of the file will not have to be loaded.
Signed-off-by: Kevin Willford <kcwillford@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The cherry_pick_list was looping through the original side checking the
seen indicator and setting the cherry_flag on the commit. If we save
off the commit in the patch_id we can set the cherry_flag on the correct
commit when running through the other side when a patch_id match is found.
Signed-off-by: Kevin Willford <kcwillford@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This change will use the hashmap from the hashmap.h to keep track of the
patch_ids that have been encountered instead of using an internal
implementation. This simplifies the implementation of the patch ids.
Signed-off-by: Kevin Willford <kcwillford@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
It turns out that the earlier effort to update the heuristics may
want to use a bit more time to mature. Turn it off by default.
* jk/diff-compact-heuristic:
diff: disable compaction heuristic for now
http://lkml.kernel.org/g/20160610075043.GA13411@sigill.intra.peff.net
reports that a change to add a new "function" with common ending
with the existing one at the end of the file is shown like this:
def foo
do_foo_stuff()
+ common_ending()
+end
+
+def bar
+ do_bar_stuff()
+
common_ending()
end
when the new heuristic is in use. In reality, the change is to add
the blank line before "def bar" and everything below, which is what
the code without the new heuristic shows.
Disable the heuristics by default, and resurrect the documentation
for the option and the configuration variables, while clearly
marking the feature as still experimental.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "are we talking with TTY, doing an interactive session?"
detection has been updated to work better for "Git for Windows".
* kb/msys2-tty:
mingw: make isatty() recognize MSYS2's pseudo terminals (/dev/pty*)
A couple of bugs around core.autocrlf have been fixed.
* tb/core-eol-fix:
convert.c: ident + core.autocrlf didn't work
t0027: test cases for combined attributes
convert: allow core.autocrlf=input and core.eol=crlf
t0027: make commit_chk_wrnNNO() reliable
Many commands normalize command line arguments from NFD to NFC
variant of UTF-8 on OSX, but commands in the "diff" family did
not, causing "git diff $path" to complain that no such path is
known to Git. They have been taught to do the normalization.
* ar/diff-args-osx-precompose:
diff: run arguments through precompose_argv
A bash-ism "local" has been removed from "git submodule" scripted
Porcelain.
* sb/submodule-helper-relative-path:
submodule: remove bashism from shell script
The way how "submodule--helper list" signals unmatch error to its
callers has been updated.
* sb/submodule-helper-list-signal-unmatch-via-exit-status:
submodule--helper: offer a consistent API
The mark-up in the top-level README.md file has been updated to
typeset CLI command names differently from the body text.
* bd/readme.markdown-more:
README.md: format CLI commands with code syntax
The manpage output of our documentation did not render well in
terminal; typeset literals in bold by default to make them stand
out more.
* em/man-bold-literal:
Documentation: bold literals in man
"git cherry-pick --help" had three instances of word "behavior",
one of which was spelled "behaviour", which is updated to match the
other two.
* pa/cherry-pick-doc-typo:
git-cherry-pick.txt: correct a small typo
"git rebase -i", after it fails to auto-resolve the conflict, had
an unnecessary call to "git rerere" from its very early days, which
was spotted recently; the call has been removed.
* js/rebase-i-dedup-call-to-rerere:
rebase -i: remove an unnecessary 'rerere' invocation
The one in 'master' has a brown-paper-bag bug that breaks the perf
test when used inside a usual Git repository with a working tree.
* js/perf-rebase-i:
perf: make the tests work without a worktree
When we run scripted Porcelains, "git" potty has set up the $PATH by
prepending $GIT_EXEC_PATH, the path given by "git --exec-path=$there
$cmd", etc. already. Because of this, scripted Porcelains can
dot-source shell script library like git-sh-setup with simple dot
without specifying any path.
t2300 however dot-sources git-sh-setup without adjusting $PATH like
the real "git" potty does. This has not been a problem so far, but
once git-sh-setup wants to rely on the $PATH adjustment, just like
any scripted Porcelains already do, it would become one. It cannot
for example dot-source another shell library without specifying the
full path to it by prefixing $(git --exec-path).
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In t5500::check_prot_host_port_path(), diagport is not a variable
used elsewhere and the function is not recursively called so this
can simply lose the "local", which may not be supported by shell
(besides, the function liberally clobbers other variables without
making them "local").
t7403::reset_submodule_urls() overrides the "root" variable used
in the test framework for no good reason; its use is not about
temporarily relocating where the test repositories are created.
This assignment can be made not to clobber the variable by moving
them into the subshells it already uses. Its value is always
$TRASH_DIRECTORY, so we could use it instead there, and this
function that is called only once and its two subshells may not be
necessary (instead, the caller can use "git -C $there config" and
set a value that is derived from $TRASH_DIRECTORY), but this is a
minimum fix that is needed to lose "local".
Helped-by: John Keeping <john@keeping.me.uk>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio pointed out `relative_path` was using bashisms via the
local variables. As the longer term goal is to rewrite most of the
submodule code in C, do it now.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 48308681 (2016-02-29, git submodule update: have a dedicated helper
for cloning), the helper communicated errors back only via exit code,
and dance with printing '#unmatched' in case of error was left to
git-submodule.sh as it uses the output of the helper and pipes it into
shell commands. This change makes the helper consistent by never
printing '#unmatched' in the helper but always handling these piping
issues in the actual shell script.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This does not change the behavior, but allows the user to tweak
DEVELOPER_CFLAGS on the command-line or in a config.mak* file if
needed.
This also makes the code somewhat cleaner as it follows the pattern
<initialisation of variables>
<include statements>
<actual build logic>
by specifying which flags to activate in the first part, and actually
activating them in the last one.
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The one-shot environment variable syntax:
FOO=BAR some-program
is unportable when some-program is actually a shell
function, like test_must_fail (on some shells FOO remains
set after the function returns, and on others it does not).
We sometimes get around this by using env, like:
test_must_fail env FOO=BAR some-program
But that only works because test_must_fail's arguments are
themselves a command which can be run. You can't run:
env FOO=BAR test_must_fail some-program
because env does not know about our shell functions. So
there is no equivalent for test_commit, for example, and one
must resort to:
(
FOO=BAR
export FOO
test_commit
)
which is a bit verbose. Let's add a version of "env" that
works _inside_ the shell, by creating a subshell, exporting
variables from its argument list, and running the command.
Its use is demonstrated on a currently-unportable case in
t4014.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Correct faulty recommendation to use "git submodule deinit ." when
de-initialising all submodules, which would result in a strange
error message in a pathological corner case.
* sb/submodule-deinit-all:
submodule deinit: require '--all' instead of '.' for all submodules
"http.cookieFile" configuration variable clearly wants a pathname,
but we forgot to treat it as such by e.g. applying tilde expansion.
* bn/http-cookiefile-config:
http: expand http.cookieFile as a path
Documentation: config: improve word ordering for http.cookieFile
Running tests with '-x' option to trace the individual command
executions is a useful way to debug test scripts, but some tests
that capture the standard error stream and check what the command
said can be broken with the trace output mixed in. When running
our tests under "bash", however, we can redirect the trace output
to another file descriptor to keep the standard error of programs
being tested intact.
* jk/test-send-sh-x-trace-elsewhere:
test-lib: set BASH_XTRACEFD automatically
