In older versions of git, we used rfc822 header folding to
indicate that the original subject line had multiple lines
in it.  But since a1f6baa5 (format-patch: wrap long header
lines, 2011-02-23), we now use header folding whenever there
is a long line.

This means that "git am" cannot trust header folding as a
sign from format-patch that newlines should be preserved.
Instead, format-patch needs to signal more explicitly that
the newlines are significant.  This patch does so by
rfc2047-encoding the newlines in the subject line. No
changes are needed on the "git am" end; it already decodes
the newlines properly.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

We have a pretty_print_context representing the parameters
for a pretty-print session, but we did not use it uniformly.
As a result, functions kept growing more and more arguments.

Let's clean this up in a few ways:

  1. All pretty-print pp_* functions now take a context.
     This lets us reduce the number of arguments to these
     functions, since we were just passing around the
     context values separately.

  2. The context argument now has a cmit_fmt field, which
     was passed around separately. That's one less argument
     per function.

  3. The context argument always comes first, which makes
     calling a little more uniform.

This drops lines from some callers, and adds lines in a few
places (because we need an extra line to set the context's
fmt field). Overall, we don't save many lines, but the lines
that are there are a lot simpler and more readable.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Many callers don't actually care about the pretty print
context at all; let's just give them a simple way of
pretty-printing a commit without having to create a context
struct.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Without the "-k" option, mailinfo will convert a folded
subject header like:

  Subject: this is a
    subject that doesn't
    fit on one line

into a single line. With "-k", however, we assumed that
these newlines were significant and represented something
that the sending side would want us to preserve.

For messages created by format-patch, this assumption was
broken by a1f6baa5 (format-patch: wrap long header lines,
2011-02-23).  For messages sent by arbitrary MUAs, this was
probably never a good assumption to make, as they may have
been folding subjects in accordance with rfc822's line
length recommendations all along.

This patch now joins folded lines with a single whitespace
character. This treats header folding purely as a syntactic
feature of the transport mechanism, not as something that
format-patch is trying to tell us about the original
subject.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Commit a1f6baa5 (format-patch: wrap long header lines,
2011-02-23) changed format-patch's behavior with respect to
long header lines, but made no accompanying changes to the
receiving side. It was thought that "git am" would handle
these folded subjects fine, but there is a regression when
using "am -k".

Let's add a test documenting this. While we're at it, let's
give more complete test coverage to document what should be
happening in each case. We test three types of subjects:
a short one, one long enough to require wrapping, and a
multiline subject. For each, we test these three
combinations:

  format-patch | am
  format-patch -k | am
  format-patch -k | am -k

We don't bother testing "format-patch | am -k", which is
nonsense (you will be adding in [PATCH] cruft to each
subject).

This reveals the regression above (long subjects have
linebreaks introduced via "format-patch -k | am -k"),
as well as an existing non-optimal behavior (multiline
subjects are not preserved using "-k").
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

We already wrap names in "from" headers, which tend to be
the long part of an address. But it's also possible for a
long name to not be wrapped, but to make us want to wrap the
email address. For example (imagine for the sake of
readability we want to wrap at 50 characters instead of 78):

  From: this is my really long git name <foo@example.com>

The name does not overflow the line, but the name and email
together do. So we would rather see:

  From: this is my really long git name
    <git@example.com>

Because we wrap the name separately during add_rfc2047, we
neglected this case. Instead, we should see how long the
final line of the wrapped name ended up, and decide whether
or not to wrap based on that. We can't break the address
into multiple parts, so we either leave it with the name, or
put it by itself on a line.

Test by Erik Faye-Lund.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

These should generally never happen, as we already
concatenate multiples in subjects into a single line. But
let's be defensive, since not encoding them means we will
output malformed headers.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Subject and identity headers may be arbitrarily long. In the
past, we just assumed that single-line headers would be
reasonably short. For multi-line subjects that we squish
into a single line, we just "pre-folded" the data in
pp_title_line by adding a newline and indentation.

There were two problems. One is that, although rare,
single-line messages can actually be longer than the
recommended line-length limits. The second is that the
pre-folding interacted badly with rfc2047 encoding, leading
to malformed headers.

Instead, let's stop pre-folding the subject lines, and just
fold everything based on length in add_rfc2047, whether
it is encoded or not.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The function strbuf_add_wrapped_text takes a NUL-terminated
string. This makes it annoying to wrap strings we have as a
pointer and a length.

Refactoring strbuf_add_wrapped_text and all of its
sub-functions to handle fixed-length strings turned out to
be really ugly. So this implementation is lame; it just
strdups the text and operates on the NUL-terminated version.
This should be fine as the strings we are wrapping are
generally pretty short.  If it becomes a problem, we can
optimize later.
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>

The "--xhtml" option is supported only in highlight < 3.0. There is no option
to enforce (X)HTML output format compatible with both highlight < 3.0 and
highlight >= 3.0. However default output format is HTML so we don't need to
explicitly specify it.
Signed-off-by: NAdam Tkac <atkac@redhat.com>
Helped-by: NJakub Narebski <jnareb@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint:
  rebase -i: clarify in-editor documentation of "exec"
  tests: sanitize more git environment variables
  fast-import: treat filemodify with empty tree as delete
  rebase: give a better error message for bogus branch
  rebase: use explicit "--" with checkout

Conflicts:
	t/t9300-fast-import.sh

The hints in the current "instruction sheet" template look like so:

 # Rebase 3f142468..a1d7e01 onto 3f142468
 #
 # Commands:
 #  p, pick = use commit
 #  r, reword = use commit, but edit the commit message
 #  e, edit = use commit, but stop for amending
 #  s, squash = use commit, but meld into previous commit
 #  f, fixup = like "squash", but discard this commit's log message
 #  x <cmd>, exec <cmd> = Run a shell command <cmd>, and stop if it fails
 #
 # If you remove a line here THAT COMMIT WILL BE LOST.
 # However, if you remove everything, the rebase will be aborted.
 #

This does not make it clear that the format of each line is

	<insn> <commit id> <explanatory text that will be printed>

but the reader will probably infer that from the automatically
generated pick examples above it.

What about the "exec" instruction?  By analogy, I might imagine that
the format of that line is "exec <command> <explanatory text>", and
the "x <cmd>" hint does not address that question (at first I read it
as taking an argument <cmd> that is the name of a shell).  Meanwhile,
the mention of <cmd> makes the hints harder to scan as a table.

So remove the <cmd> and add some words to remind the reader that
"exec" runs a command named by the rest of the line.  To make room, it
is left to the manpage to explain that that command is run using
$SHELL and that nonzero status from that command will pause the
rebase.

Wording from Junio.
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

These variables should generally not be set in one's
environment, but they do get set by rebase, which means
doing an interactive rebase like:

  pick abcd1234 foo
  exec make test

will cause false negatives in the test suite.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* jn/fast-import-empty-tree-removal:
  fast-import: treat filemodify with empty tree as delete

Normal git processes do not allow one to build a tree with an empty
subtree entry without trying hard at it.  This is in keeping with the
general UI philosophy: git tracks content, not empty directories.

v1.7.3-rc0~75^2 (2010-06-30) changed that by making it easy to include
an empty subtree in fast-import's active commit:

	M 040000 4b825dc642cb6eb9a060e54bf8d69288fbee4904 subdir

One can trigger this by reading an empty tree (for example, the tree
corresponding to an empty root commit) and trying to move it to a
subtree.  It is better and more closely analogous to 'git read-tree
--prefix' to treat such commands as requests to remove the subtree.
Noticed-by: NDavid Barr <david.barr@cordelta.com>
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When you give a non-existent branch to git-rebase, it spits
out the usage. This can be confusing, since you may
understand the usage just fine, but simply have made a
mistake in the branch name.

Before:

  $ git rebase origin bogus
  Usage: git rebase ...

After:

  $ git rebase origin bogus
  fatal: no such branch: bogus
  Usage: git rebase ...
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In the case of a ref/pathname conflict, checkout will
already do the right thing and checkout the ref. However,
for a non-existant ref, this has two advantages:

  1. If a file with that pathname exists, rebase will
     refresh the file from the index and then rebase the
     current branch instead of producing an error.

  2. If no such file exists, the error message using an
     explicit "--" is better:

       # before
       $ git rebase -i origin bogus
       error: pathspec 'bogus' did not match any file(s) known to git.
       Could not checkout bogus

       # after
       $ git rebase -i origin bogus
       fatal: invalid reference: bogus
       Could not checkout bogus

The problems seem to be trigger-able only through "git
rebase -i", as regular git-rebase checks the validity of the
branch parameter as a ref very early on. However, it doesn't
hurt to be defensive.
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>

* as/userdiff-pascal:
  userdiff: match Pascal class methods

* jn/setup-fixes:
  t1510: fix typo in the comment of a test
  Documentation updates for 'GIT_WORK_TREE without GIT_DIR' historical usecase
  Subject: setup: officially support --work-tree without --git-dir
  tests: compress the setup tests
  tests: cosmetic improvements to the repo-setup test
  t/README: hint about using $(pwd) rather than $PWD in tests
  Fix expected values of setup tests on Windows

Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

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

The original intention of --work-tree was to allow people to work in a
subdirectory of their working tree that does not have an embedded .git
directory.  Because their working tree, which their $cwd was in, did not
have an embedded .git, they needed to use $GIT_DIR to specify where it is,
and because this meant there was no way to discover where the root level
of the working tree was, so we needed to add $GIT_WORK_TREE to tell git
where it was.

However, this facility has long been (mis)used by people's scripts to
start git from a working tree _with_ an embedded .git directory, let git
find .git directory, and then pretend as if an unrelated directory were
the associated working tree of the .git directory found by the discovery
process.  It happens to work in simple cases, and is not worth causing
"regression" to these scripts.
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The current treatment of "git reset --keep" emphasizes how it
differs from --hard (treatment of local changes) and how it breaks
down into plumbing (git read-tree -m -u HEAD <commit> followed by git
update-ref HEAD <commit>).  This can discourage people from using
it, since it might seem to be a complex or niche option.

Better to emphasize what the --keep flag is intended for --- moving
the index and worktree from one commit to another, like "git checkout"
would --- so the reader can make a more informed decision about the
appropriate situations in which to use it.
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The errno check added in commit 3ba7a065 "A loose object is not corrupt
if it cannot be read due to EMFILE" only checked for whether errno is
not ENOENT and thus incorrectly treated "no error" as an error
condition.

Because of that, it never reached the code path that would report that
the object is corrupted and instead caused funny errors like:

  fatal: failed to read object 333c4768ce595793fdab1ef3a036413e2a883853: Success

So we have to extend the check to cover the case in which the object
file was successfully read, but its contents are corrupted.
Reported-by: NWill Palmer <wmpalmer@gmail.com>
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

New test helpers:

 - setup_repo, to initialize a repository or gitfile pointing to a
   repository, with core.bare and core.worktree set as specified;

 - try_case, to run setup from a given directory and validate the
   result, with GIT_DIR and GIT_WORK_TREE set as specified;

 - try_repo, to initialize a repository and call "try_case" from the
   toplevel and a subdirectory;

 - run_wt_tests, to run a battery of tests that check for sane
   behavior when GIT_WORK_TREE is set to various positions relative to
   the .git dir and cwd.

Use these helpers to make the test shorter, less repetitive, and (one
hopes) easier to understand and modify.
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Give an overview in "sh t1510-repo-setup.sh --help" output.
Waste some vertical and horizontal space for clearer code.
Signed-off-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* maint:
  exec_cmd: remove unused extern

This definition was added by commit 77cb17e9, but it's left unused since
commit 511707d4. Remove the left-over definition.
Signed-off-by: NErik Faye-Lund <kusmabite@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

* jn/gitweb-no-logo:
  gitweb: make logo optional

* jk/diff-driver-binary-doc:
  docs: explain diff.*.binary option

* tr/submodule-relative-scp-url:
  submodule: fix relative url parsing for scp-style origin

* rj/maint-difftool-cygwin-workaround:
  difftool: Fix failure on Cygwin

* rj/maint-test-fixes:
  t9501-*.sh: Fix a test failure on Cygwin
  lib-git-svn.sh: Add check for mis-configured web server variables
  lib-git-svn.sh: Avoid setting web server variables unnecessarily
  t9142: Move call to start_httpd into the setup test
  t3600-rm.sh: Don't pass a non-existent prereq to test #15

* jn/maint-gitweb-pathinfo-fix:
  gitweb: Fix handling of whitespace in generated links

* ak/describe-exact:
  describe: Delay looking up commits until searching for an inexact match
  describe: Store commit_names in a hash table by commit SHA1
  describe: Do not use a flex array in struct commit_name
  describe: Use for_each_rawref

* jn/maint-fast-import-object-reuse:
  fast-import: insert new object entries at start of hash bucket

* jn/submodule-b-current:
  git submodule: Remove now obsolete tests before cloning a repo
  git submodule -b ... of current HEAD fails

* jc/maint-svn-info-test-fix:
  t9119: do not compare "Text Last Updated" line from "svn info"