Document that the meaning of a Signed-off-by trailer can vary from
project to project in the end-user documentation, and clarify what
it means to this project.

* bk/sob-dco:
  Documentation: stylistically normalize references to Signed-off-by:
  SubmittingPatches: clarify DCO is our --signoff rule
  Documentation: clarify and expand description of --signoff
  doc: preparatory clean-up of description on the sign-off option

Test-coverage enhancement of running commit-graph task "git
maintenance" as needed led to discovery and fix of a bug.

* ds/maintenance-commit-graph-auto-fix:
  maintenance: core.commitGraph=false prevents writes
  maintenance: test commit-graph auto condition

When "git commit-graph" detects the same commit recorded more than
once while it is merging the layers, it used to die.  The code now
ignores all but one of them and continues.

* ds/commit-graph-merging-fix:
  commit-graph: don't write commit-graph when disabled
  commit-graph: ignore duplicates when merging layers

A test helper "test_cmp A B" was taught to diagnose missing files A
or B as a bug in test, but some tests legitimately wanted to notice
a failure to even create file B as an error, in addition to leaving
the expected result in it, and were misdiagnosed as a bug.  This
has been corrected.

* es/test-cmp-typocatcher:
  Revert "test_cmp: diagnose incorrect arguments"

"git fast-import" wasted a lot of memory when many marks were in use.

* jk/fast-import-marks-alloc-fix:
  fast-import: fix over-allocation of marks storage

The side-band status report can be sent at the same time as the
primary payload multiplexed, but the demultiplexer on the receiving
end incorrectly split a single status report into two, which has
been corrected.

* js/avoid-split-sideband-message:
  sideband: report unhandled incomplete sideband messages as bugs
  sideband: avoid reporting incomplete sideband messages

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Docfix.

* cc/doc-filter-branch-typofix:
  filter-branch doc: fix filter-repo typo

In 2.29, "--committer-date-is-author-date" option of "rebase" and
"am" subcommands lost the e-mail address by mistake, which has been
corrected.

* jk/committer-date-is-author-date-fix:
  rebase: fix broken email with --committer-date-is-author-date
  am: fix broken email with --committer-date-is-author-date
  t3436: check --committer-date-is-author-date result more carefully

"git fsck" and the corresponding check done during the transport
learned to ensure that in-tree files like `.gitignore` and
`.gitattributes` are not symbolic links.

* jk/symlinked-dotgitx-files:
  docs: document symlink restrictions for .git* files

GitHub Actions automated test improvement to skip tests on a tree
identical to what has already been tested.

* js/ci-ghwf-dedup-tests:
  ci: make the "skip-if-redundant" check more defensive
  ci: work around old records of GitHub runs

"git resurrect" script (in contrib/) learned that the object names
may be longer than 40-hex depending on the hash function in use.

* dl/resurrect-update-for-sha256:
  contrib/git-resurrect.sh: use hash-agnostic OID pattern
  contrib/git-resurrect.sh: indent with tabs

Micro clean-up.

* cm/t7xxx-cleanup:
  t7102: prepare expected output inside test_expect_* block
  t7201: put each command on a separate line
  t7201: use 'git -C' to avoid subshell
  t7102,t7201: remove whitespace after redirect operator
  t7102,t7201: remove unnecessary blank spaces in test body
  t7101,t7102,t7201: modernize test formatting

Micro clean-up of a test script.

* ct/t0000-use-test-path-is-file:
  t0000: use test_path_is_file instead of "test -f"

Work around flakiness in a test.

* en/t7518-unflake:
  t7518: fix flaky grep invocation

Docfix.

* cc/doc-filter-branch-typofix:
  filter-branch doc: fix filter-repo typo

In 2.29, "--committer-date-is-author-date" option of "rebase" and
"am" subcommands lost the e-mail address by mistake, which has been
corrected.

* jk/committer-date-is-author-date-fix:
  rebase: fix broken email with --committer-date-is-author-date
  am: fix broken email with --committer-date-is-author-date
  t3436: check --committer-date-is-author-date result more carefully

We outlawed symbolic link versions of various .git files in 10ecfa76
(verify_path: disallow symlinks in .gitmodules, 2018-05-04) and
dd4c2fe6 (verify_path(): disallow symlinks in .gitattributes and
.gitignore, 2020-10-05). The reasons are discussed in detail there, but
we never adjusted the documentation to let users know.

This hasn't been a big deal since the point is that such setups were
mildly broken and thought to be unusual anyway. But it certainly doesn't
hurt to be clear and explicit about it.
Suggested-by: NPhilip Oakley <philipoakley@iee.email>
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Commit 7573cec5 (rebase -i: support --committer-date-is-author-date,
2020-08-17) copied the committer ident-parsing code from builtin/am.c.
And in doing so, it copied a bug in which we always set the email to an
empty string. We fixed the version in git-am in the previous commit;
this commit fixes the copied code.
Reported-by: NVenomVendor <info@venomvendor.com>
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Commit e8cbe211 (am: stop exporting GIT_COMMITTER_DATE, 2020-08-17)
rewrote the code for setting the committer date to use fmt_ident(),
rather than setting an environment variable and letting commit_tree()
handle it. But it introduced two bugs:

  - we use the author email string instead of the committer email

  - when parsing the committer ident, we used the wrong variable to
    compute the length of the email, resulting in it always being a
    zero-length string

This commit fixes both, which causes our test of this option via the
rebase "apply" backend to now succeed.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

After running "rebase --committer-date-is-author-date", we confirm that
the committer date is the same as the author date. However, we don't
look at any other parts of the committer ident line to make sure we
didn't screw them up. And indeed, there are a few bugs here. Depending
on the rebase backend in use, we may accidentally use the author email
instead of the committer's, or even an empty string.

Let's teach our test_ctime_is_atime helper to check the committer name
and email, which reveals several failing tests.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Brown-paper-bag fix.

* js/no-builtins-on-disk-option:
  SKIP_DASHED_BUILT_INS: do not skip the bin/ programs

Brown-paper-bag fix.

* js/no-builtins-on-disk-option:
  SKIP_DASHED_BUILT_INS: do not skip the bin/ programs

This reverts commit 20438c11, reversing
changes made to 63707257.

This reverts commit 571e16d6, reversing
changes made to fdf196b9.

That way we can notice if there is a breakage/bug in the parts of
the test that prepare the expected outcome, which is how modern
tests are arranged.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Modern practice is to avoid multiple commands per line,
and instead place each command on its own line.
Signed-off-by: NCharvi Mendiratta <charvi077@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NCharvi Mendiratta <charvi077@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

According to Documentation/CodingGuidelines, redirect
operator is written with space before, but no space
after them.

Let's remove these whitespaces after redirect operators.
Signed-off-by: NCharvi Mendiratta <charvi077@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The idea of the `SKIP_DASHED_BUILT_INS` option is to stop hard-linking
the built-in commands as separate executables. The patches to do that
specifically excluded the three commands `receive-pack`,
`upload-archive` and `upload-pack`, though: these commands are expected
to be present in the `PATH` in their dashed form on the server side of
any fetch/push.

However, due to an oversight by myself, even if those commands were
still hard-linked, they were not installed into `bin/`.
Noticed-by: NMichael Forney <mforney@mforney.org>
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: NTaylor Blau <me@ttaylorr.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

It was pretty tricky to verify that incomplete sideband messages are
handled correctly by the `recv_sideband()`/`demultiplex_sideband()`
code: they have to be flushed out at the end of the loop in
`recv_sideband()`, but the actual flushing is done by the
`demultiplex_sideband()` function (which therefore has to know somehow
that the loop will be done after it returns).

To catch future bugs where incomplete sideband messages might not be
shown by mistake, let's catch that condition and report a bug.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In 2b695ecd (t5500: count objects through stderr, not trace,
2020-05-06) we tried to ensure that the "Total 3" message could be
grepped in Git's output, even if it sometimes got chopped up into
multiple lines in the trace machinery.

However, the first instance where this mattered now goes through the
sideband machinery, where it is _still_ possible for messages to get
chopped up: it *is* possible for the standard error stream to be sent
byte-for-byte and hence it can be easily interrupted. Meaning: it is
possible for the single line that we're looking for to be chopped up
into multiple sideband packets, with a primary packet being delivered
between them.

This seems to happen occasionally in the `vs-test` part of our CI
builds, i.e. with binaries built using Visual C, but not when building
with GCC or clang; The symptom is that t5500.43 fails to find a line
matching `remote: Total 3` in the `log` file, which ends in something
along these lines:

	remote: Tota
	remote: l 3 (delta 0), reused 0 (delta 0), pack-reused 0

This should not happen, though: we have code in `demultiplex_sideband()`
_specifically_ to stitch back together lines that were delivered in
separate sideband packets.

However, this stitching was broken in a subtle way in fbd76cd4
(sideband: reverse its dependency on pkt-line, 2019-01-16): before that
change, incomplete sideband lines would not be flushed upon receiving a
primary packet, but after that patch, they would be.

The subtleness of this bug comes from the fact that it is easy to get
confused by the ambiguous meaning of the `break` keyword: after writing
the primary packet contents, the `break;` in the original version of
`recv_sideband()` does _not_ break out of the `while` loop, but instead
only ends the `switch` case:

	while (!retval) {
		[...]
		switch (band) {
			[...]
		case 1:
/* Write the contents of the primary packet */
			write_or_die(out, buf + 1, len);
/* Here, we do *not* break out of the loop, `retval` is unchanged */
			break;
		[...]
	}

	if (outbuf.len) {
/* Write any remaining sideband messages lacking a trailing LF */
		strbuf_addch(&outbuf, '\n');
		xwrite(2, outbuf.buf, outbuf.len);
	}

In contrast, after fbd76cd4 (sideband: reverse its dependency on
pkt-line, 2019-01-16), the body of the `while` loop was extracted into
`demultiplex_sideband()`, crucially _including_ the logic to write
incomplete sideband messages:

	switch (band) {
	[...]
	case 1:
		*sideband_type = SIDEBAND_PRIMARY;
/* This does not break out of the loop: the loop is in the caller */
		break;
	[...]
	}

cleanup:
	[...]
/* This logic is now no longer _outside_ the loop but _inside_ */
	if (scratch->len) {
		strbuf_addch(scratch, '\n');
		xwrite(2, scratch->buf, scratch->len);
	}

The correct way to fix this is to return from `demultiplex_sideband()`
early. The caller will then write out the contents of the primary packet
and continue looping. The `scratch` buffer for incomplete sideband
messages is owned by that caller, and will continue to accumulate the
remainder(s) of those messages. The loop will only end once
`demultiplex_sideband()` returned non-zero _and_ did not indicate a
primary packet, which is the case only when we hit the `cleanup:` path,
in which we take care of flushing any unfinished sideband messages and
release the `scratch` buffer.

To ensure that this does not get broken again, we introduce a pair of
subcommands of the `pkt-line` test helper that specifically chop up the
sideband message and squeeze a primary packet into the middle.

Final note: The other test case touched by 2b695ecd (t5500: count
objects through stderr, not trace, 2020-05-06) is not affected by this
issue because the sideband machinery is not involved there.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

t7102 and t7201 still follow the old style of having blank
lines around test body, which is not consistence with our
current practice.

Let's remove those unnecessary blank lines.
Signed-off-by: NCharvi Mendiratta <charvi077@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Some tests in these scripts are formatted using a very old style:
        test_expect_success \
            'title' \
            'body line 1 &&
             body line 2'

Updating the formatting to the modern style:
        test_expect_success 'title' '
            body line 1 &&
            body line 2
        '
Signed-off-by: NCharvi Mendiratta <charvi077@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The name of the tool is 'git-filter-repo' not
'git-repo-filter'.
Signed-off-by: NChristian Couder <chriscool@tuxfamily.org>
Reviewed-by: NElijah Newren <newren@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This reverts commit d572f52a; the
idea to detect that "test_cmp expect actual" was fed a misspelt
filename meant well, but when the version of Git tested exhibits a
bug, the reason why these two files do not match may be because one
of them did not get created as expected, in which case missing file
is not a sign of misspelt filename but is a genuine test failure.
Acked-by: NEric Sunshine <sunshine@sunshineco.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>