test-lib: self-test that --verbose works

t0000 contains some light self-tests of test-lib.sh, but --verbose was
not covered.  Add a test.

The only catch is that the presence of a test harness influences the
output (specifically, the presence of some empty lines).  So we need
to unset TEST_HARNESS or set it to a known value.  Leaving it unset
leads to spurious test failures in the final summary, which come from
the subtest.  So we always set it.

Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: verbose mode for only tests matching a pattern

With the new --verbose-only=<pattern> option, one can enable --verbose
at a per-test granularity.  The pattern is matched against the test
number, e.g.

  ./t0000-basic.sh --verbose-only='2[0-2]'

to see only the full output of test 20-22, while showing the rest in the
one-liner format.

As suggested by Jeff King, this takes care to wrap the entire
test_expect_* block, but nothing else, in the verbose toggling.  We
can use the test_start/end functions from the previous commit for the
purpose.

This is arguably not *too* useful on its own, but makes the next patch
easier to follow.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: valgrind for only tests matching a pattern

With the new --valgrind-only=<pattern> option, one can enable
--valgrind at a per-test granularity, exactly analogous to
--verbose-only from the previous commit.

The options are wired such that --valgrind implies --verbose (as
before), but --valgrind-only=<pattern> implies
--verbose-only=<pattern> unless --verbose is also in effect.

Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: allow prefixing a custom string before "ok N" etc.

This is not really meant for external use, and thus not documented. It
allows the next commit to neatly distinguish between sub-tests and the
main run.

The format is intentionally not valid TAP.  The use in the next commit
would not result in anything valid either way, and it seems better to
make it obvious.

Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
test-lib: support running tests under valgrind in parallel

With the new --valgrind-parallel=<n> option, we support running the
tests in a single test script under valgrind in parallel using 'n'
processes.

This really follows the dumbest approach possible, as follows:

* We spawn the test script 'n' times, using a throw-away
  TEST_OUTPUT_DIRECTORY.  Each of the instances is given options that
  ensures that it only runs every n-th test under valgrind, but
  together they cover the entire range.

* We add up the numbers from the individual tests, and provide the
  usual output.

This is really a gross hack at this point, and should be improved.  In
particular we should keep the actual outputs somewhere more easily
discoverable, and summarize them to the user.

Nevertheless, this is already workable and gives a speedup of more
than 2 on a dual-core (hyperthreaded) machine, using n=4.  This is
expected since the overhead of valgrind is so big (on the order of 20x
under good conditions, and a large startup overhead at every git
invocation) that redundantly running the non-valgrind tests in between
is not that expensive.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
add -i: add extra options at the right place in "diff" command line

Appending "--diff-algorithm=histogram" at the end of canned command
line for various modes of "diff" is correct for most of them but not
for "stash" that has a non-option already wired in, like so:

	'stash' => {
		DIFF => 'diff-index -p HEAD',

Appending an extra option after non-option may happen to work due to
overly lax command line parser, but that is not something we should
rely on.  Instead, splice in the extra argument immediately after the
command name (i.e. 'diff-index', 'diff-files', etc.).

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jk/commit-info-slab' into jch

Allow adding custom information to commit objects in order to
represent unbound number of flag bits etc.

* jk/commit-info-slab:
  commit-slab: introduce a macro to define a slab for new type
  commit-slab: avoid large realloc
  commit: allow associating auxiliary info on-demand
Merge branch 'jc/topo-author-date-sort' (early part) into jch

* 'jc/topo-author-date-sort' (early part):
  log: --author-date-order
  sort-in-topological-order: use prio-queue
  prio-queue: priority queue of pointers to structs
  toposort: rename "lifo" field

Conflicts:
	.gitignore
	Makefile
	revision.c
Merge branch 'jk/add-i-custom-diff-algo' (early part) into jch

* 'jk/add-i-custom-diff-algo' (early part):
  add--interactive: respect diff.algorithm
Merge branch 'fg/submodule-non-ascii-path' into jch

Many "git submodule" operations do not work on a submodule at a
path whose name is not in ASCII.

* fg/submodule-non-ascii-path:
  t7400: test of UTF-8 submodule names pass under Mac OS
  handle multibyte characters in name
Merge branch 'fc/sequencer-plug-leak' into jch

Plug a small leak in an error codepath.

* fc/sequencer-plug-leak:
  sequencer: avoid leaking message buffer when refusing to create an empty commit
  sequencer: remove useless indentation
Merge branch 'jh/libify-note-handling' into jch

Make it possible to call into copy-notes API from the sequencer code.

* jh/libify-note-handling:
  Move create_notes_commit() from notes-merge.c into notes-utils.c
  Move copy_note_for_rewrite + friends from builtin/notes.c to notes-utils.c
  finish_copy_notes_for_rewrite(): Let caller provide commit message
Merge branch 'mm/rm-coalesce-errors' into jch

Give a single message followed by list of paths from "git rm" to
report multiple paths that cannot be removed.

* mm/rm-coalesce-errors:
  rm: introduce advice.rmHints to shorten messages
  rm: better error message on failure for multiple files

# Conflicts:
# 	advice.c
# 	advice.h
Merge branch 'rr/rebase-sha1-by-string-query' into jch

Allow various commit objects to be given to "git rebase" by ':/look
for this string' syntax, e.g. "git rebase --onto ':/there'".

* rr/rebase-sha1-by-string-query:
  rebase: use peel_committish() where appropriate
  sh-setup: add new peel_committish() helper
  t/rebase: add failing tests for a peculiar revision

# Conflicts:
# 	t/t3400-rebase.sh
Merge branch 'rs/unpack-trees-tree-walk-conflict-field' into jch

Code clean-up.

* rs/unpack-trees-tree-walk-conflict-field:
  unpack-trees: don't shift conflicts left and right
Merge branch 'dk/maint-t5150-dirname' into jch

Fix a test script.

* dk/maint-t5150-dirname:
  tests: allow sha1's as part of the path
Merge branch 'dk/version-gen-gitdir' into jch

Allow packaging a tarball in a working tree with $GIT_DIR set elsewhere.

* dk/version-gen-gitdir:
  GIT-VERSION-GEN: support non-standard $GIT_DIR path
Merge branch 'fg/submodule-fixup' into jch

Code cleanup.

* fg/submodule-fixup:
  git-submodule.sh: remove duplicate call to set_rev_name
Merge branch 'jk/doc-build-move-infordir-def' into jch

Makefile cleanup.

* jk/doc-build-move-infordir-def:
  Documentation/Makefile: move infodir to be with other '*dir's
  Documentation/Makefile: fix spaces around assignments
Merge branch 'jk/mergetool-lib-refactor' into jch

Code cleanup.

* jk/mergetool-lib-refactor:
  mergetool--lib: refactor {diff,merge}_cmd logic