builtin rebase: use oideq()

Use oideq() instead of !oidcmp(), as it is more idiomatic, and might
give the compiler more opportunities to optimize.

Patch generated with 'contrib/coccinelle/free.cocci' and Coccinelle
v1.0.7 (previous Coccinelle versions don't notice this).

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin rebase: use FREE_AND_NULL

Use the macro FREE_AND_NULL to release memory allocated for
'head_name' and clear its pointer.

Patch generated with 'contrib/coccinelle/free.cocci' and Coccinelle
v1.0.7 (previous Coccinelle versions don't notice this).

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

describe doc: remove '7-char' abbreviation reference

While the minimum is 7-char, the unambiguous length can be longer.

Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

rerere doc: quote `rerere.enabled`

Signed-off-by: Philip Oakley <philipoakley@iee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

blame: default to HEAD in a bare repo when no start commit is given

When 'git blame' is invoked without specifying the commit to start
blaming from, it starts from the given file's state in the work tree.
However, when invoked in a bare repository without a start commit,
then there is no work tree state to start from, and it dies with the
following error message:

$ git rev-parse --is-bare-repository
true
$ git blame file.c
fatal: this operation must be run in a work tree

This is misleading, because it implies that 'git blame' doesn't work
in bare repositories at all, but it does, in fact, work just fine when
it is given a commit to start from.

We could improve the error message, of course, but let's just default
to HEAD in a bare repository instead, as most likely that is what the
user wanted anyway (if they wanted to start from an other commit, then
they would have specified that in the first place).

'git annotate' is just a thin wrapper around 'git blame', so in the
same situation it printed the same misleading error message, and this
patch fixes it, too.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

ls-files: use correct format string

struct stat_data and struct cache_time both use unsigned ints for all
their members. However the format string for 'git ls-files --debug'
currently uses %d for formatting these numbers. This means that we
potentially print these values incorrectly if they are greater than
INT_MAX.

This has been the case since the --debug option was introduced in 'git
ls-files' in 8497421715 ("ls-files: learn a debugging dump format",
2010-07-31).

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: remove incorrect reference to gc.auto=0

The chance of a repository being corrupted due to a "gc" has nothing
to do with whether or not that "gc" was invoked via "gc --auto", but
whether there's other concurrent operations happening.

This is already noted earlier in the paragraph, so there's no reason
to suggest this here. The user can infer from the rest of the
documentation that "gc" will run automatically unless gc.auto=0 is
set, and we shouldn't confuse the issue by implying that "gc --auto"
is somehow more prone to produce corruption than a normal "gc".

Well, it is in the sense that a blocking "gc" would stop you from
doing anything else in *that* particular terminal window, but users
are likely to have another window, or to be worried about how
concurrent "gc" on a server might cause corruption.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: clarify that "gc" doesn't throw away referenced objects

Amend the "NOTES" section to fix up wording that's been with us since
3ffb58be0a ("doc/git-gc: add a note about what is collected",
2008-04-23).

I can't remember when/where anymore (I think Freenode #Git), but at
some point I was having a conversation with someone who was convinced
that "gc" would prune things only referenced by e.g. refs/pull/*, and
pointed to this section as proof.

It turned out that they'd read the "branches and tags" wording here
and thought just refs/{heads,tags}/* and refs/remotes/* etc. would be
kept, which is what we enumerate explicitly.

So let's say "other refs", even though just above we say "objects that
are referenced anywhere in your repository".

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: note "gc --aggressive" in "fast-import"

Amend the "PACKFILE OPTIMIZATION" section in "fast-import" to explain
that simply running "git gc --aggressive" after a "fast-import" should
properly optimize the repository. This is simpler and more effective
than the existing "repack" advice (which I'm keeping as it helps
explain things) because it e.g. also packs the newly imported refs.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: downplay the usefulness of --aggressive

The existing "gc --aggressive" docs come just short of recommending to
users that they run it regularly. I've personally talked to many users
who've taken these docs as an advice to use this option, and have,
usually it's (mostly) a waste of time.

So let's clarify what it really does, and let the user draw their own
conclusions.

Let's also clarify the "The effects [...] are persistent" to
paraphrase a brief version of Jeff King's explanation at [1].

1. https://public-inbox.org/git/20190318235356.GK29661@sigill.intra.peff.net/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: note how --aggressive impacts --window & --depth

Since 07e7dbf0db (gc: default aggressive depth to 50, 2016-08-11) we
somewhat confusingly use the same depth under --aggressive as we do by
default.

As noted in that commit that makes sense, it was wrong to make more
depth the default for "aggressive", and thus save disk space at the
expense of runtime performance, which is usually the opposite of
someone who'd like "aggressive gc" wants.

But that's left us with a mostly-redundant configuration variable, so
let's clearly note in its documentation that it doesn't change the
default.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: fix formatting for "gc.writeCommitGraph"

Change the AsciiDoc formatting so that an example of "gc --auto" isn't
rendered as "git-gc(1) --auto", but as "git gc --auto". This is
consistent with the rest of the links and command examples in this
documentation.

The formatting I'm changing was initially introduced in
d5d5d7b641 ("gc: automatically write commit-graph files", 2018-06-27).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: re-flow the "gc.*" section in "config"

Re-flow the "gc.*" section in "config". A previous commit moved this
over from the "gc" docs, but tried to keep as many of the lines
identical to benefit from diff's move detection.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

gc docs: include the "gc.*" section from "config" in "gc"

Rather than duplicating the documentation for the various "gc" options
let's include the "gc" docs from git-config. They were mostly better
already, and now we don't have the same docs in two places with subtly
different wording.

In the cases where the git-gc(1) docs were saying something the "gc"
docs in git-config(1) didn't cover move the relevant section over to
the git-config(1) docs.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: switch directory rename detection default

When all of x/a, x/b, and x/c have moved to z/a, z/b, and z/c on one
branch, there is a question about whether x/d added on a different
branch should remain at x/d or appear at z/d when the two branches are
merged. There are different possible viewpoints here:

A) The file was placed at x/d; it's unrelated to the other files in
x/ so it doesn't matter that all the files from x/ moved to z/ on
one branch; x/d should still remain at x/d.

B) x/d is related to the other files in x/, and x/ was renamed to z/;
therefore x/d should be moved to z/d.

Since there was no ability to detect directory renames prior to
git-2.18, users experienced (A) regardless of context. Choice (B) was
implemented in git-2.18, with no option to go back to (A), and has been
in use since. However, one user reported that the merge results did not
match their expectations, making the change of default problematic,
especially since there was no notice printed when directory rename
detection moved files.

Note that there is also a third possibility here:

C) There are different answers depending on the context and content
that cannot be determined by git, so this is a conflict. Use a
higher stage in the index to record the conflict and notify the
user of the potential issue instead of silently selecting a
resolution for them.

Add an option for users to specify their preference for whether to use
directory rename detection, and default to (C). Even when directory
rename detection is on, add notice messages about files moved into new
directories.

As a sidenote, x/d did not have to be a new file here; it could have
already existed at some other path and been renamed to x/d, with
directory rename detection just renaming it again to z/d. Thus, it's
not just new files, but also a modification to all rename types (normal
renames, rename/add, rename/delete, rename/rename(1to1),
rename/rename(1to2), and rename/rename(2to1)).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: give callers of handle_content_merge() access to contents

Pass a merge_file_info struct to handle_content_merge() so that the
callers can access the oid and mode of the result afterward.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: track information associated with directory renames

Directory rename detection previously silently applied. In order to
allow printing information about paths that changed or printing a
conflict notification (and only doing so near other potential conflict
messages associated with the paths), save this information inside the
rename struct for later use. A subsequent patch will make use of the
additional information.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t6043: fix copied test description to match its purpose

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: switch from (oid,mode) pairs to a diff_filespec

There was a significant inconsistency in the various parts of the API
used in merge-recursive; many places used a pair of (oid, mode) to track
file version/contents, while other parts used a diff_filespec (which
have an oid and mode embedded in it). This inconsistency caused lots of
places to need to pack and unpack data to call into other functions.
This has been the subject of some past cleanups (see e.g. commit
0270a07ad0b2 ("merge-recursive: remove final remaining caller of
merge_file_one()", 2018-09-19)), but let's just remove the underlying
mess altogether by switching to use diff_filespec.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: cleanup handle_rename_* function signatures

Instead of passing various bits and pieces of 'ci', just pass it
directly.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: track branch where rename occurred in rename struct

We previously tracked the branch associated with a rename in a separate
field in rename_conflict_info, but since it is directly associated with
the rename it makes more sense to move it into the rename struct.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: remove ren[12]_other fields from rename_conflict_info

The ren1_other and ren2_other fields were synthesized from information
in ren1->src_entry and ren2->src_entry. Since we already have the
necessary information in ren1 and ren2, just use those.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: shrink rename_conflict_info

The rename_conflict_info struct used both a pair and a stage_data which
were taken from a rename struct. Just use the original rename struct.
This will also allow us to start making other simplifications to the
code.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: move some struct declarations together

These structs are related and reference each other, so move them
together to make it easier for folks to determine what they hold and
what their purpose is.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: use 'ci' for rename_conflict_info variable name

We used a couple different names, but used 'ci' the most. Use the same
variable name throughout for a little extra consistency.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: rename locals 'o' and 'a' to 'obuf' and 'abuf'

Since we want to replace oid,mode pairs with a single diff_filespec,
we will soon want to be able to use the names 'o', 'a', and 'b' for
the three different file versions. Rename some local variables in
blob_unchanged() that would otherwise conflict.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: rename diff_filespec 'one' to 'o'

In the previous commit, we noted that several places throughout merge
recursive both had a reason to use 'o'; some for a merge_options struct,
and others for a diff_filespec struct. Some places had both, forcing
one of the two to be renamed, though the choice was inconsistent. Now
that the merge_options struct has been renamed to 'opt' everywhere, we
can replace the few places that used 'one' for the diff_filespec to 'o'.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive: rename merge_options argument from 'o' to 'opt'

The name 'o' was used for the merge_options struct pointer taken by many
functions, but in a few places it was named 'opt'. Several functions
that didn't need merge_options instead used 'o' for a diff_filespec
argument or local. Some functions needed both an inconsistently either
renamed the merge_options to 'opt' or the diff_filespec to 'one'. I
want to remove the weird split in the codebase between using a
diff_filespec and a pair of (oid,mode) values in favor of using a
diff_filespec everywhere, but that dramatically increases the number of
cases where we want to use 'o' as a diff_filespec. Rename the
merge_options argument to 'opt' to make room.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Use 'unsigned short' for mode, like diff_filespec does

struct diff_filespec defines mode to be an 'unsigned short'. Several
other places in the API which we'd like to interact with using a
diff_filespec used a plain unsigned (or unsigned int). This caused
problems when taking addresses, so switch to unsigned short.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff: batch fetching of missing blobs

When running a command like "git show" or "git diff" in a partial clone,
batch all missing blobs to be fetched as one request.

This is similar to c0c578b33c ("unpack-trees: batch fetching of missing
blobs", 2017-12-08), but for another command.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t: move 'hex2oct' into test-lib-functions.sh

The helper 'hex2oct' is used to convert base-16 encoded data into a
base-8 binary form, and is useful for preparing data for commands that
accept input in a binary format, such as 'git hash-object', via
'printf'.

This helper is defined identically in three separate places throughout
't'. Move the definition to test-lib-function.sh, so that it can be used
in new test suites, and its definition is not redundant.

This will likewise make our job easier in the subsequent commit, which
also uses 'hex2oct'.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

progress: assemble percentage and counters in a strbuf before printing

The following patches in this series want to handle the progress bar's
title and changing parts (i.e. the counter and the optional percentage
and throughput combined) differently, and need to know the length
of the changing parts of the previously displayed progress bar.

To prepare for those changes assemble the changing parts in a separate
strbuf kept in 'struct progress' before printing.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

progress: make display_progress() return void

Ever since the progress infrastructure was introduced in 96a02f8f6d
(common progress display support, 2007-04-18), display_progress() has
returned an int, telling callers whether it updated the progress bar
or not. However, this is:

- useless, because over the last dozen years there has never been a
single caller that cared about that return value.

- not quite true, because it doesn't print a progress bar when
running in the background, yet it returns 1; see 85cb8906f0
(progress: no progress in background, 2015-04-13).

The related display_throughput() function returned void already upon
its introduction in cf84d51c43 (add throughput to progress display,
2007-10-30).

Let's make display_progress() return void, too. While doing so
several return statements in display() become unnecessary, remove
them.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tag: fix formatting

Wrap usage line at '<tagname>'. Also, wrap strings with '\n' at the end
of string fragments instead of at the beginning of the next string
fragment.

Convert a space-indent into a tab-indent for style.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

ci: fix AsciiDoc/Asciidoctor stderr check in the documentation build job

In 'ci/test-documentation.sh' we save the standard error of 'make
doc', and, in an attempt to make sure that neither AsciiDoc nor
Asciidoctor printed any warnings, we check the emptiness of the
resulting file with '! test -s stderr.log'. This check has never
actually worked, because in our 'ci/*' build scripts we rely on 'set
-e' aborting the build job when a command exits with error, and,
unfortunately, the combination of the two doesn't work as intended.
According to POSIX [1]:

"The -e setting shall be ignored when executing [...] a pipeline
beginning with the ! reserved word" [2]

Watch and learn:

$ echo unexpected >file
$ ( set -e; ! test -s file ; echo "should not reach this" ) ; echo $?
should not reach this
0

This is why we haven't noticed the warnings from Asciidoctor that were
fixed in the first patches of this patch series, though some of them
were already there in the build of v2.18.0-rc0 [3].

Check the emptiness of that file with 'test ! -s' instead, which works
properly with 'set -e':

$ ( set -e; test ! -s file ; echo "should not reach this" ) ; echo $?
1

Furthermore, dump the contents of that file to the log for our
convenience, so if it were to unexpectedly end up being non-empty,
then we wouldn't have to scroll through all that long build log
looking for warnings, but could see them right away near the end of
the log.

Note that we are only really interested in the standard error of
AsciiDoc and Asciidoctor, but by saving the stderr of 'make doc' we
also save any error output from the make rules. Currently there is
only one such line: we build the docs with Asciidoctor right after a
'make clean', meaning that 'make USE_ASCIIDOCTOR=1 doc' always starts
with running 'GIT-VERSION-GEN', which in turn prints the version to
stderr. A 'sed' command was supposed to remove this version line to
prevent it from triggering that (previously defunct) emptiness check,
but, unfortunately, this command doesn't work as intended, either,
because it leaves the file to be checked intact, but that defunct
emptiness check hid this issue, too... Furthermore, in the near
future there will be an other line on stderr, because commit
9a71722b4d (Doc: auto-detect changed build flags, 2019-03-17) in the
currently cooking branch 'ma/doc-diff-doc-vs-doctor-comparison' will
print "* new asciidoc flags" at the beginning of both 'make doc'
invokations.

Extend that 'sed' command to remove this line, too, wrap it in a
helper function so the output of both 'make doc' is filtered the same
way, and change its invokation to actually write the logfile to be
checked.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set

[2] POSIX doesn't discuss the meaning of '! cmd' in case of simple
commands, but it defines that "A pipeline is a sequence of one or
more commands separated by the control operator '|'", so
apparently a simple command is considered as pipeline as well.

http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_02

[3] https://travis-ci.org/git/git/jobs/385932007#L1463

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

ci: stick with Asciidoctor v1.5.8 for now

The recent release of Asciidoctor v2.0.0 broke our documentation
build job on Travis CI, where we 'gem install asciidoctor', which
always brings us the latest and (supposedly) greatest. Alas, we are
not ready for that just yet, because it removed support for DocBook
4.5, and we have been requiring that particular DocBook version to
build 'user-manual.xml' with Asciidoctor, resulting in:

ASCIIDOC user-manual.xml
asciidoctor: FAILED: missing converter for backend 'docbook45'. Processing aborted.
Use --trace for backtrace
make[1]: *** [user-manual.xml] Error 1

Unfortunately, we can't simply switch to DocBook 5 right away, as
doing so leads to validation errors from 'xmlto', and working around
those leads to yet another errors... [1]

So let's stick with Asciidoctor v1.5.8 (latest stable release before
v2.0.0) in our documentation build job on Travis CI for now, until we
figure out how to deal with the fallout from Asciidoctor v2.0.0.

[1] https://public-inbox.org/git/20190324162131.GL4047@pobox.com/

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

send-email: don't cc *-by lines with '-' prefix

Since commit ef0cc1df90f6b ("send-email: also pick up cc addresses from
-by trailers") in git version 2.20, git send-email adds to cc list
addresses from all *-by lines. As a side effect a line with
'-Signed-off-by' is now also added to cc. This makes send-email pick
lines from patches that remove patch files from the git repo. This is
common in the Buildroot project that often removes (and adds) patch
files that have 'Signed-off-by' in their patch description part.

Consider only *-by lines that start with [a-z] (case insensitive) to
avoid unrelated addresses in cc.

Cc: Joe Perches <joe@perches.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

cocci: FLEX_ALLOC_MEM to FLEX_ALLOC_STR

Ensure that a FLEX_MALLOC_MEM that uses 'strlen' for its 'len' uses
FLEX_ALLOC_STR instead, since these are equivalent forms.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

midx.c: convert FLEX_ALLOC_MEM to FLEX_ALLOC_STR

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

revision: use a prio_queue to hold rewritten parents

This patch fixes a quadratic list insertion in rewrite_one() when
pathspec limiting is combined with --parents. What happens is something
like this:

1. We see that some commit X touches the path, so we try to rewrite
its parents.

2. rewrite_one() loops forever, rewriting parents, until it finds a
relevant parent (or hits the root and decides there are none). The
heavy lifting is done by process_parent(), which uses
try_to_simplify_commit() to drop parents.

3. process_parent() puts any intermediate parents into the
&revs->commits list, inserting by commit date as usual.

So if commit X is recent, and then there's a large chunk of history that
doesn't touch the path, we may add a lot of commits to &revs->commits.
And insertion by commit date is O(n) in the worst case, making the whole
thing quadratic.

We tried to deal with this long ago in fce87ae538 (Fix quadratic
performance in rewrite_one., 2008-07-12). In that scheme, we cache the
oldest commit in the list; if the new commit to be added is older, we
can start our linear traversal there. This often works well in practice
because parents are older than their descendants, and thus we tend to
add older and older commits as we traverse.

But this isn't guaranteed, and in fact there's a simple case where it is
not: merges. Imagine we look at the first parent of a merge and see a
very old commit (let's say 3 years old). And on the second parent, as we
go back 3 years in history, we might have many commits. That one
first-parent commit has polluted our oldest-commit cache; it will remain
the oldest while we traverse a huge chunk of history, during which we
have to fall back to the slow, linear method of adding to the list.

Naively, one might imagine that instead of caching the oldest commit,
we'd start at the last-added one. But that just makes some cases faster
while making others slower (and indeed, while it made a real-world test
case much faster, it does quite poorly in the perf test include here).
Fundamentally, these are just heuristics; our worst case is still
quadratic, and some cases will approach that.

Instead, let's use a data structure with better worst-case performance.
Swapping out revs->commits for something else would have repercussions
all over the code base, but we can take advantage of one fact: for the
rewrite_one() case, nobody actually needs to see those commits in
revs->commits until we've finished generating the whole list.

That leaves us with two obvious options:

1. We can generate the list _unordered_, which should be O(n), and
then sort it afterwards, which would be O(n log n) total. This is
"sort-after" below.

2. We can insert the commits into a separate data structure, like a
priority queue. This is "prio-queue" below.

I expected that sort-after would be the fastest (since it saves us the
extra step of copying the items into the linked list), but surprisingly
the prio-queue seems to be a bit faster.

Here are timings for the new p0001.6 for all three techniques across a
few repositories, as compared to master:

master cache-last sort-after prio-queue
--------------------------------------------------------------------------------------------
GIT_PERF_REPO=git.git
0.52(0.50+0.02) 0.53(0.51+0.02) +1.9% 0.37(0.33+0.03) -28.8% 0.37(0.32+0.04) -28.8%

GIT_PERF_REPO=linux.git
20.81(20.74+0.07) 20.31(20.24+0.07) -2.4% 0.94(0.86+0.07) -95.5% 0.91(0.82+0.09) -95.6%

GIT_PERF_REPO=llvm-project.git
83.67(83.57+0.09) 4.23(4.15+0.08) -94.9% 3.21(3.15+0.06) -96.2% 2.98(2.91+0.07) -96.4%

A few items to note:

- the cache-list tweak does improve the bad case for llvm-project.git
that started my digging into this problem. But it performs terribly
on linux.git, barely helping at all.

- the sort-after and prio-queue techniques work well. They approach
the timing for running without --parents at all, which is what you'd
expect (see below for more data).

- prio-queue just barely outperforms sort-after. As I said, I'm not
really sure why this is the case, but it is. You can see it even
more prominently in this real-world case on llvm-project.git:

git rev-list --parents 07ef786652e7 -- llvm/test/CodeGen/Generic/bswap.ll

where prio-queue routinely outperforms sort-after by about 7%. One
guess is that the prio-queue may just be more efficient because it
uses a compact array.

There are three new perf tests:

- "rev-list --parents" gives us a baseline for running with --parents.
This isn't sped up meaningfully here, because the bad case is
triggered only with simplification. But it's good to make sure we
don't screw it up (now, or in the future).

- "rev-list -- dummy" gives us a baseline for just traversing with
pathspec limiting. This gives a lower bound for the next test (and
it's also a good thing for us to be checking in general for
regressions, since we don't seem to have any existing tests).

- "rev-list --parents -- dummy" shows off the problem (and our fix)

Here are the timings for those three on llvm-project.git, before and
after the fix:

Test master prio-queue
------------------------------------------------------------------------------
0001.3: rev-list --parents 2.24(2.12+0.12) 2.22(2.11+0.11) -0.9%
0001.5: rev-list -- dummy 2.89(2.82+0.07) 2.92(2.89+0.03) +1.0%
0001.6: rev-list --parents -- dummy 83.67(83.57+0.09) 2.98(2.91+0.07) -96.4%

Changes in the first two are basically noise, and you can see we
approach our lower bound in the final one.

Note that we can't fully get rid of the list argument from
process_parents(). Other callers do have lists, and it would be hard to
convert them. They also don't seem to have this problem (probably
because they actually remove items from the list as they loop, meaning
it doesn't grow so large in the first place). So this basically just
drops the "cache_ptr" parameter (which was used only by the one caller
we're fixing here) and replaces it with a prio_queue. Callers are free
to use either data structure, depending on what they're prepared to
handle.

Reported-by: Björn Pettersson A <bjorn.a.pettersson@ericsson.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/completion: add smerge to the mergetool completion candidates

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

mergetools: add support for smerge (Sublime Merge)

Teach difftool and mergetool about the Sublime Merge "smerge" command.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

blame.c: don't drop origin blobs as eagerly

When a parent blob already has chunks queued up for blaming, dropping
the blob at the end of one blame step will cause it to get reloaded
right away, doubling the amount of I/O and unpacking when processing a
linear history.

Keeping such parent blobs in memory seems like a reasonable optimization
that should incur additional memory pressure mostly when processing the
merges from old branches.

Signed-off-by: David Kastrup <dak@gnu.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

doc: promote "git switch"

The new command "git switch" is added to avoid the confusion of
one-command-do-all "git checkout" for new users. They are also helpful
to avoid ambiguation context.

For these reasons, promote it everywhere possible. This includes
documentation, suggestions/advice from other commands...

The "Checking out files" progress line in unpack-trees.c is also updated
to "Updating files" to be neutral to both git-checkout and git-switch.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

completion: support switch

Completion support for --guess could be made better. If no --detach is
given, we should only provide a list of refs/heads/* and dwim ones,
not the entire ref space. But I still can't penetrate that
__git_refs() function yet.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t: add tests for switch

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: make --orphan switch to an empty tree

Switching and creating branches always involves knowing the
<start-point> to begin the new branch from. Sometimes, people want to
create a new branch that does not have any commits yet; --orphan is a
flag to allow that.

--orphan overrides the default of HEAD for <start-point> instead causing
us to start from an empty history with all tracked files removed from
the index and working tree. The use of --orphan is incompatible with
specifying a <start-point>.

A note on the implementation. An alternative is just create a dummy
commit in-core with empty tree and switch to it. But there's a chance
the commit's SHA-1 may end up somewhere permanent like reflog. It's best
to make sure "commit" pointer is NULL to avoid it.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: reject if some operation is in progress

Unless you know what you're doing, switching to another branch to do
something then switching back could be confusing. Worse, you may even
forget that you're in the middle of something. By the time you realize,
you may have done a ton of work and it gets harder to go back.

A new option --ignore-in-progress was considered but dropped because it
was not exactly clear what should happen. Sometimes you can switch away
and get back safely and resume the operation. Sometimes not. And the
git-checkout behavior is automatically clear merge/revert/cherry-pick,
which makes it a bit even more confusing [1].

We may revisit and add this option in the future. But for now play it
safe and not allow it (you can't even skip this check with --force). The
user is suggested to cancel the operation by themselves (and hopefully
they do consider the consequences, not blindly type the command), or to
create a separate worktree instead of switching. The third option is
the good old "git checkout", but it's not mentioned.

[1] CACsJy8Axa5WsLSjiscjnxVK6jQHkfs-gH959=YtUvQkWriAk5w@mail.gmail.com

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: no worktree status unless real branch switch happens

When we switch from one branch to another, it makes sense to show a
summary of local changes since there could be conflicts, or some files
left modified.... When switch is used solely for creating a new
branch (and "switch" to the same commit) or detaching, we don't really
need to show anything.

"git checkout" does it anyway for historical reasons. But we can start
with a clean slate with switch and don't have to.

This essentially reverts fa655d8411 (checkout: optimize "git checkout
-b <new_branch>" - 2018-08-16) and make it default for switch,
but also for -B and --detach. Users of big repos are encouraged to
move to switch.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: implicit dwim, use --no-guess to disable it

This is already the default in git-checkout. The real change in here is
just minor cleanup. The main excuse is to explain why dwim is kept default.

Contrary to detach mode that is easy to get into and confusing to get
back out. Automatically creating a tracking branch often does not kick
in as often (you would need a branch of the same name on a remote). And
since the branch creation is reported clearly, the user should be able
to undo/delete it if it's unwanted.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: add short option for --detach

"git checkout" automatically detaches branches and --detach is not
that useful (--no-detach is more likely). But for "switch", you
may want to use it more often once you're used to detached HEAD. This
of course adds -d to git-checkout but it does not harm (yet?) to do it.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: only allow explicit detached HEAD

"git checkout <commit>" will checkout the commit in question and
detach HEAD from the current branch. It is naturally a right thing to
do once you get git references. But detached HEAD is a scary concept
to new users because we show a lot of warnings and stuff, and it could
be hard to get out of (until you know better).

To keep switch a bit more friendly to new users, we only allow
entering detached HEAD mode when --detach is given. "git
switch" must take a branch (unless you create a new branch,
then of course switch can take any commit-ish)

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: reject "do nothing" case

"git checkout" can be executed without any arguments. What it does is
not exactly great: it switches from HEAD to HEAD and shows worktree
modification as a side effect.

Make switch reject this case. Just use "git status" if you want
that side effect. For switch, you have to either

- really switch a branch
- (explicitly) detach from the current branch
- create a new branch

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: stop accepting pathspec

This command is about switching branch (or creating a new one) and
should not accept pathspec. This helps simplify ambiguation
handling. The other two ("git checkout" and "git restore") of
course do accept pathspec as before.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: remove -l

This option is ancient. Nowadays reflog is enabled by default and
automatically created for new branches. Keep it in git-checkout only.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: add --discard-changes

--discard-changes is a better name than --force for this option since
it's what really happens. --force is turned to an alias for
--discard-changes. But it's meant to be an alias for potentially more
force options in the future.

Side note. It's not obvious from the patch but --discard-changes also
affects submodules if --recurse-submodules is used. The knob to force
updating submodules is hidden behind unpack-trees.c

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

switch: better names for -b and -B

The shortcut of these options do not make much sense when used with
switch. And their descriptions are also tied to checkout. Move -b/-B
to cmd_checkout() and new -c/-C with the same functionality in
cmd_switch_branch()

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: split part of it to new command 'switch'

"git checkout" doing too many things is a source of confusion for many
users (and it even bites old timers sometimes). To remedy that, the
command will be split into two new ones: switch and restore. The good
old "git checkout" command is still here and will be until all (or most
of users) are sick of it.

See the new man page for the final design of switch. The actual
implementation though is still pretty much the same as "git checkout"
and not completely aligned with the man page. Following patches will
adjust their behavior to match the man page.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: split options[] array in three pieces

This is a preparation step for introducing new commands that do parts
of what checkout does. There will be two new commands, one is about
switching branches, detaching HEAD... one about checking out
paths. These share the a subset of command line options. The rest of
command line options are separate.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: move 'confict_style' and 'dwim_..' to checkout_opts

These local variables are referenced by struct option[]. This struct
will soon be broken down, moved away and we can't rely on local
variables anymore. Move these two to struct checkout_opts in
preparation for that.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: make "opts" in cmd_checkout() a pointer

"opts" will soon be moved out of cmd_checkout(). To keep changes in
that patch smaller, convert "opts" to a pointer and keep the real
thing behind "real_opts".

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: factor out some code in parse_branchname_arg()

This is in preparation for the new command restore, which also
needs to parse opts->source_tree but does not need all the
disambiguation logic.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: keep most #include sorted

The include list becomes very long and frankly a bit unorganized. With
the exception of builtin.h, cache.h or git-compat-util.h which have to
come first, keep the rest sorted.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: inform the user when removing branch state

After a successful switch, if a merge, cherry-pick or revert is ongoing,
it is canceled. This behavior has been with us from the very early
beginning, soon after git-merge was created but never actually
documented [1]. It may be a good idea to be transparent and tell the
user if some operation is canceled.

I consider this a better way of telling the user than just adding a
sentence or two in git-checkout.txt, which will be mostly ignored
anyway.

PS. Originally I wanted to print more details like

warning: cancelling an in-progress merge from <SHA-1>

which may allow some level of undo if the user wants to. But that seems
a lot more work. Perhaps it can be improved later if people still want
that.

[1] ... and I will try not to argue whether it is a sensible behavior.
There is some more discussion here if people are interested:
CACsJy8Axa5WsLSjiscjnxVK6jQHkfs-gH959=YtUvQkWriAk5w@mail.gmail.com

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

checkout: advice how to get out of detached HEAD mode

Detached HEAD mode is considered dangerous and confusing for newcomers
and we print a big block of warning how to move forward. But we should
also suggest the user the way to get out of it if they get into detached
HEAD by mistake.

While at there, I also suggest how to turn the advice off. This is
another thing I find annoying with advices and should be dealt with in a
more generic way. But that may require some refactoring in advice.c
first.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t: rename t2014-switch.sh to t2014-checkout-switch.sh

The old name does not really say that this is about 'checkout -b'. See
49d833dc07 (Revert "checkout branch: prime cache-tree fully" -
2009-05-12) for more information

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-checkout.txt: fix monospace typeset

Add backticks where we have none, replace single quotes with backticks
and replace double-quotes. Drop double-quotes from nested constructions
such as `"@{-1}"`.

Helped-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

doc: document --overwrite-ignore

I added this option in git-checkout and git-merge in c1d7036b6b
(checkout,merge: disallow overwriting ignored files with
--no-overwrite-ignore - 2011-11-27) but did not remember to update
documentation. This completes that commit.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-checkout.txt: fix one syntax line

<branch> can be omitted in this syntax, and it's actually documented a
few paragraphs down:

You could omit <branch>, in which case the command degenerates to
"check out the current branch", which is a glorified no-op with
rather expensive side-effects to show only the tracking information,
if exists, for the current branch.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-checkout.txt: spell out --no-option

It's easier to search for and also less cryptic.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: respect excluded paths when detecting branches

Currently, excluded paths are only handled in the following cases:
* no branch detection;
* branch detection with using clientspec.

However, excluded paths are not respected in case of
branch detection without using clientspec.

Fix this by consulting the list of excluded paths
when splitting files across branches.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: add failing test for "git-p4: respect excluded paths when detecting branches"

In preparation for a fix, add a failing test case to test that
git-p4 doesn't exclude files despite being told to
when handling multiple branches.

I.e., it should exclude //depot/branch2/file2 when run with -//depot/branch2/file2,
but doesn't do this right now.

The test is based on 'git p4 clone complex branches' test with the following changes:
* account for file3 moved from branch3 to branch4 in test 'git p4 submit to two branches in a single changelist';
* account for branch6 created in test 'git p4 clone file subset branch';
* file2 is expected to be missing from all branches due to explicit exclude.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: don't exclude other files with same prefix

Make sure not to exclude files unintentionally
if exclude paths are specified without a trailing /.
I.e., don't exclude "//depot/file_dont_exclude" if run with "-//depot/file".

Do this by ensuring that paths without a trailing "/" are only matched completely.

Also, abort path search on the first match as a micro-optimization.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: add failing test for "don't exclude other files with same prefix"

In preparation for a fix, add a failing test case to test that
git-p4 doesn't exclude files with the same prefix unintentionally
when exclude paths are specified without a trailing /.
I.e., don't exclude "//depot/file_dont_exclude" if run with "-//depot/file".
or don't exclude "//depot/discard_file_not" if run with "-//depot/discard_file".

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: don't groom exclude path list on every commit

Currently, `cloneExclude` array is being groomed (by removing trailing "...")
on every changeset.
(since `extractFilesFromCommit()` is called on every imported changeset)

As a micro-optimization, do it once while parsing arguments.
Also, prepend "/" and remove trailing "..." at the same time.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: match branches case insensitively if configured

git-p4 knows how to handle case insensitivity in file paths
if core.ignorecase is set.
However, when determining a branch for a file,
it still does a case-sensitive prefix match.
This may result in some file changes to be lost on import.

For example, given the following commits
1. add //depot/main/file1
2. add //depot/DirA/file2
3. add //depot/dira/file3
4. add //depot/DirA/file4
and "branchList = main:DirA" branch mapping,
commit 3 will be lost.

So, do branch search case insensitively if running with core.ignorecase set.
Teach splitFilesIntoBranches() to use the p4PathStartsWith() function
for path prefix matches instead of always case-sensitive match.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: add failing test for "git-p4: match branches case insensitively if configured"

In preparation for a fix, add a failing test case to test that
git-p4 doesn't fold the case in file paths
when doing branch detection case insensitively.
(i.e. when core.ignorecase is set)

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4: detect/prevent infinite loop in gitCommitByP4Change()

Under certain circumstances, gitCommitByP4Change() can enter an infinite
loop resulting in `git p4 sync` hanging forever.

The problem is that
`git rev-list --bisect <latest> ^<earliest>` can return `<latest>`,
which would result in reinspecting <latest> and potentially an infinite loop.

This can happen when importing just a subset of P4 repository
and/or with explicit "--changesfile" option.

A real-life example:
"""
looking in ref refs/remotes/p4/mybranch for change 26894 using bisect...
Reading pipe: git rev-parse refs/remotes/p4/mybranch
trying: earliest latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git cat-file commit 147f5d3292af2e1cc4a56a7b96db845144c68486
current change 25339
trying: earliest ^147f5d3292af2e1cc4a56a7b96db845144c68486 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^147f5d3292af2e1cc4a56a7b96db845144c68486
Reading pipe: git cat-file commit 51db83df9d588010d0bd995641c85aa0408a5bb9
current change 25420
trying: earliest ^51db83df9d588010d0bd995641c85aa0408a5bb9 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^51db83df9d588010d0bd995641c85aa0408a5bb9
Reading pipe: git cat-file commit e8f83909ceb570f5a7e48c2853f3c5d8207cea52
current change 25448
trying: earliest ^e8f83909ceb570f5a7e48c2853f3c5d8207cea52 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^e8f83909ceb570f5a7e48c2853f3c5d8207cea52
Reading pipe: git cat-file commit 09a48eb7acd594dce52e06681be9c366e1844d66
current change 25521
trying: earliest ^09a48eb7acd594dce52e06681be9c366e1844d66 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^09a48eb7acd594dce52e06681be9c366e1844d66
Reading pipe: git cat-file commit 4daff81c520a82678e1ef347f2b5e97258101ae1
current change 26907
trying: earliest ^09a48eb7acd594dce52e06681be9c366e1844d66 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^09a48eb7acd594dce52e06681be9c366e1844d66
Reading pipe: git cat-file commit 4daff81c520a82678e1ef347f2b5e97258101ae1
current change 26907
trying: earliest ^09a48eb7acd594dce52e06681be9c366e1844d66 latest 4daff81c520a82678e1ef347f2b5e97258101ae1
Reading pipe: git rev-list --bisect 4daff81c520a82678e1ef347f2b5e97258101ae1 ^09a48eb7acd594dce52e06681be9c366e1844d66
Reading pipe: git cat-file commit 4daff81c520a82678e1ef347f2b5e97258101ae1
current change 26907
...
"""

The fix is two-fold:
* detect an infinite loop and die right away
instead of looping forever;
* make sure, `git rev-list --bisect` can't return "latestCommit" again
by excluding it from the rev-list range explicitly.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

read-tree.txt: clarify --reset and worktree changes

The description of --reset stays true to the first implementation in
438195cced (git-read-tree: add "--reset" flag, 2005-06-09). That is,
--reset discards unmerged entries. Or at least true to the commit
message because I can't be sure about read-tree's behavior regarding
local changes.

But in fcc387db9b (read-tree -m -u: do not overwrite or remove untracked
working tree files., 2006-05-17), it is clear that "-m -u" tries to keep
local changes, while --reset is singled out and will keep overwriting
worktree files. It's not stated in the commit message, but it's obvious
from the patch.

I went this far back not because I had a lot of free time, but because I
did not trust my reading of unpack-trees.c code. So far I think the
related changes in history agree with my understanding of the current
code, that "--reset" loses local changes.

This behavior is not mentioned in git-read-tree.txt, even though
old-timers probably can just guess it based on the "reset" name. Update
git-read-tree.txt about this.

Side note. There's another change regarding --reset that is not
obviously about local changes, b018ff6085 (unpack-trees: fix "read-tree
-u --reset A B" with conflicted index, 2012-12-29). But I'm pretty sure
this is about the first function of --reset, to discard unmerged entries
correctly.

PS. The patch changes one more line than necessary because the first
line uses spaces instead of tab.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests (pack-objects): use the full, unabbreviated `--revs` option

To use the singular form of a word, when the option wants the plural
form (and quietly expands it because it thinks it was abbreviated), is
an easy mistake to make, and t5317 contains almost two dozen of them.

However, using abbreviated options in tests is a bit fragile, so we will
disallow use of abbreviated options in our test suite.

In preparation for this change, let's fix
`t5317-pack-objects-filter-objects.sh`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests (status): spell out the `--find-renames` option in full

To avoid future ambiguities, we really want to use full option names in
the test suite. `t7525-status-rename.sh` used an abbreviated form of the
`--find-renames` option, though, so let's change that.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests (push): do not abbreviate the `--follow-tags` option

We really want to spell out the option in the full form, to avoid any
ambiguity that might be introduced by future patches.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t5531: avoid using an abbreviated option

It was probably just an oversight: the `--recurse-submodules` option
puts the term "submodules" in the plural form, not the singular one.

To avoid future problems in case that another option is introduced that
starts with the prefix `--recurse-submodule`, let's just fix this.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t7810: do not abbreviate `--no-exclude-standard` nor `--invert-match`

This script used abbreviated options, which is unnecessarily fragile.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests (rebase): spell out the `--force-rebase` option

In quite a few test cases, we were sloppy and used the abbreviation
`--force`, but we really should be precise in what we want to test.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

tests (rebase): spell out the `--keep-empty` option

This test wants to run `git rebase` with the `--keep-empty` option, but
it really only spelled out `--keep` and trusted Git's option parsing to
determine that this was a unique abbreviation of the real option.

However, Denton Liu contributed a patch series in
https://public-inbox.org/git/cover.1553354374.git.liu.denton@gmail.com/
that introduces a new `git rebase` option called `--keep-base`, which
makes this previously unique abbreviation non-unique.

Whether this patch series is accepted or not, it is actually a bad
practice to use abbreviated options in our test suite, because of the
issue that those unique option names are not guaranteed to stay unique
in the future.

So let's just not use abbreviated options in the test suite.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

index-pack: show progress while checking objects

When 'git index-pack' is run by 'git clone', its check_objects()
function usually doesn't take long enough to be a concern, but I just
run into a situation where it took about a minute or so: I
inadvertently put some memory pressure on my tiny laptop while cloning
linux.git, and then there was quite a long silence between the
"Resolving deltas" and "Checking connectivity" progress bars.

Show a progress bar during the loop of check_objects() to let the user
know that something is still going on.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t6050: redirect expected error output to a file

Otherwise the error from `git rev-parse` is uselessly
polluting the debug output.

Redirecting to a file, instead of /dev/null, makes it
possible to check that we got the error we expected, so
let's check that too.

Reviewed-by: Taylor Blau <me@ttaylorr.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t6050: use test_line_count instead of wc -l

This modernizes a test and makes it more portable.

Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-status: fix titles in porcelain v2 section

Asciidoc uses either one-line or two-line syntax for document/section
titles[1]. The two-line form is used in git-status. Fix a few section
titles in the porcelain v2 section which were inadvertently using
markdown syntax.

[1] http://asciidoc.org/userguide.html#X17

Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/rev-list-options: wrap --date=<format> block with "--"

Using "+" to continue multiple list items is more tedious and
error-prone than wrapping the entire block with "--" block markers.

When using asciidoctor, the list items after the --date=iso list items
are incorrectly formatted when using "+" continuation. Use "--" block
markers to correctly format the block.

When using asciidoc there is no change in how the content is rendered.

Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

test-lib: whitelist GIT_TR2_* in the environment

Add GIT_TR2_* to the whitelist of environment variables that we don't
clear when running the test suite.

This allows us to use the test suite to produce trace2 test data,
which is handy to e.g. write consumers that collate the trace data
itself.

One caveat here is that we produce trace output for not *just* the
tests, but also e.g. from this line in test-lib.sh:

# It appears that people try to run tests without building...
"${GIT_TEST_INSTALLED:-$GIT_BUILD_DIR}/git$X" >/dev/null
[...]

I consider this not just OK but a feature. Let's log *all* the git
commands we're going to execute, not just those within
test_expect_*().

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack: binary search when storing wanted-refs

In do_fetch_pack_v2(), the "sought" array is sorted by name, and it is
not subsequently reordered (within the function). Therefore,
receive_wanted_refs() can assume that "sought" is sorted, and can thus
use a binary search when storing wanted-refs retrieved from the server.

Replace the existing linear search with a binary search. This improves
performance significantly when mirror cloning a repository with more
than 1 million refs.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

interpret-trailers.txt: start the desc line with a capital letter

This description line is shown in 'git help -a' and all other commands
description starts with an uppercase character. This just makes that
printout a bit nicer.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sha1-file: support OBJECT_INFO_FOR_PREFETCH

Teach oid_object_info_extended() to support a new flag that inhibits
fetching of missing objects. This is equivalent to setting
fetch_is_missing to 0, calling oid_object_info_extended(), then setting
fetch_if_missing to whatever it was before. Update unpack-trees.c to use
this new flag instead of repeatedly setting fetch_if_missing.

This new flag complicates things slightly in that there are now 2 ways
to do the same thing. But this eliminates the need to repeatedly set a
global variable, and more importantly, allows prefetching to be done in
parallel (in the future); hence, this patch.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack: respect --no-update-shallow in v2

In protocol v0, when sending "shallow" lines, the server distinguishes
between lines caused by the remote repo being shallow and lines caused
by client-specified depth settings. Unless "--update-shallow" is
specified, there is a difference in behavior: refs that reach the former
"shallow" lines, but not the latter, are rejected. But in v2, the server
does not, and the client treats all "shallow" lines like lines caused by
client-specified depth settings.

Full restoration of v0 functionality is not possible without protocol
change, but we can implement a heuristic: if we specify any depth
setting, treat all "shallow" lines like lines caused by client-specified
depth settings (that is, unaffected by "--no-update-shallow"), but
otherwise, treat them like lines caused by the remote repo being shallow
(that is, affected by "--no-update-shallow"). This restores most of v0
behavior, except in the case where a client fetches from a shallow
repository with depth settings.

This patch causes a test that previously failed with
GIT_TEST_PROTOCOL_VERSION=2 to pass.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack: call prepare_shallow_info only if v0

In fetch_pack(), be clearer that there is no shallow information before
the fetch when v2 is used - memset the struct shallow_info to 0 instead
of calling prepare_shallow_info().

This patch is in preparation for a future patch in which a v2 fetch
might call prepare_shallow_info() after shallow info has been retrieved
during the fetch, so I needed to ensure that prepare_shallow_info() is
not called before the fetch.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Merge branch 'jt/test-protocol-version' into jt/fetch-no-update-shallow-in-proto-v2

* jt/test-protocol-version:
t5552: compensate for v2 filtering ref adv.
tests: fix protocol version for overspecifications
t5700: only run with protocol version 1
t5512: compensate for v0 only sending HEAD symrefs
t5503: fix overspecification of trace expectation
tests: always test fetch of unreachable with v0
t5601: check ssh command only with protocol v0
tests: define GIT_TEST_PROTOCOL_VERSION

ci: install Asciidoctor in 'ci/install-dependencies.sh'

When our '.travis.yml' was split into several 'ci/*' scripts [1], the
installation of the 'asciidoctor' gem somehow ended up in
'ci/test-documentation.sh'.

Install it in 'ci/install-dependencies.sh', where we install other
dependencies of the Documentation build job as well (asciidoc,
xmlto).

[1] 657343a602 (travis-ci: move Travis CI code into dedicated scripts,
2017-09-10)

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/technical/protocol-v2.txt: fix formatting

Asciidoctor versions v1.5.7 or later print the following warning while
building the documentation:

ASCIIDOC technical/protocol-v2.html
asciidoctor: WARNING: protocol-v2.txt: line 38: unterminated listing block

This highlights an issue (even with older Asciidoctor versions) where
the 'Initial Client Request' header is not rendered as a header but in
monospace. I'm not sure what exactly causes this issue and why it's
an issue only with this particular header, but all headers in
'protocol-v2.txt' are written like this:

Initial Client Request
------------------------

i.e. the header itself is indented by a space, and the "underline" is
two characters longer than the header.

Dropping that indentation and making the length of the underline match
the length of the header apparently fixes this issue.

While at it, adjust all other headers 'protocol-v2.txt' as well, to
match the style we use everywhere else.

The page rendered with AsciiDoc doesn't have this formatting issue.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>