difftool: parse options using Getopt::Long

Replace custom option/argument parser with standard Getopt::Long
module.  This shortens the code and makes it easier to understand.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: add '--no-gui' option

This commit teaches difftool to handle the '--no-gui' option. This option
negates the existing '--gui' option. The last setting given on the command
line wins.

This allows a user to configure "[alias] mdt = difftool --gui", but still
have the ability to override the setting without error:

$ git mdt --no-gui

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: exit(0) when usage is printed

Prior to this commit, the script exited with an error whenever the
usage string was printed, regardless of the reason it was done. In
cases where usage was printed due to a user request (e.g. '-h'
option), the script should exit without error (exit 0).

This commit adds an argument to the usage function that allows the
exit code to be specified when the function is called.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: remove explicit change of PATH

Adding the script directory to PATH is not needed. The script is
located at '$(git --exec-path)', which is already on the PATH.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: stop appending '.exe' to git

The system call to Git works the same whether or not ".exe" is
appended to "git". The extra code is not necessary.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: eliminate setup_environment function

Removing this function shortens the code and makes it easier to read.
Now all environment variables are set as part of procedural operation.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: teach difftool to handle directory diffs

When 'difftool' is called to compare a range of commits that modify
more than one file, it opens a separate instance of the diff tool for
each file that changed.

The new '--dir-diff' option copies all the modified files to a temporary
location and runs a directory diff on them in a single instance of the
diff tool.

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
difftool: print list of valid tools with '--tool-help'

Since bc7a96a (mergetool--lib: Refactor tools into separate files,
2011-08-18), it is possible to add a new diff tool by creating a simple
script in the '$(git --exec-path)/mergetools' directory.  Updating the
difftool help text is still a manual process, and the documentation can
easily go out of sync.

This commit teaches difftool the '--tool-help' option, which:
  - Reads the list of valid tools from 'mergetools/*'
  - Determines which of them are actually installed
  - Determines which are capable of diffing (i.e. not just a merge tool)
  - Prints the resulting list for the user

Signed-off-by: Tim Henigan <tim.henigan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
log-tree: use custom line terminator in line termination mode

When using a custom format in line termination mode (as opposed to line
separation mode), the configured line terminator is not used, so things
like "git log --pretty=tformat:%H -z" do not work properly.

Make it use the line terminator the user ordered.

Signed-off-by: Jan Krüger <jk@jk.gs>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
log-tree: the previous one is still not quite right

The correct output would have NUL after each commit, so "-z --format=%s"
would have a single-liner subject with the line-terminating LF replaced
with NUL, and "-p/--stat -z --format=%s" would have a single-liner subject
with its line-terminating LF, followed by the diff/diffstat in which the
terminating LF of the last line is replaced with NUL, but to be consistent
with what "-p/--stat -z --pretty=format:%s" does, I think it is OK to
append NUL to the diff/diffstat part instead of replacing its last LF with
NUL.

The added test shows the update is still not right for "-p -z --format".

Signed-off-by: Junio C Hamano <gitster@pobox.com>
t4006: Windows do not have /dev/zero

We only need to have a file with _some_ binary contents; be nice to
our Windows friends and avoid using /dev/zero

Signed-off-by: Johannes Sixt <j.sixt@viscovery.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-svn: introduce SVN version comparison function

With double-digit version components in SVN::Core::VERSION,
a naive string comparison is no longer sufficient and
a numeric comparison is required for correct results.

This fixes a regression introduced in
commit 082afee621aeb2d3746c8ae290af98823f981f34
("git-svn: use platform specific auth providers")
where SVN version "1.6.6" was incorrectly assumed to
be newer than the required "1.6.12" version.

[mk: fix namespace references]
[ew: commit message]

Tested-by: Matthijs Kooijman <matthijs@stdin.nl>
Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'zj/diff-empty-chmod' into next

Portability fix-up for windows.

By Johannes Sixt
* zj/diff-empty-chmod:
  t4006: Windows do not have /dev/zero
Merge branch 'th/difftool-diffall' into next

Roll the two-directory-diff logic from diffall script (in contrib/) into
"git difftool" framework.

By Tim Henigan
* th/difftool-diffall:
  difftool: print list of valid tools with '--tool-help'
  difftool: teach difftool to handle directory diffs
  difftool: eliminate setup_environment function
  difftool: stop appending '.exe' to git
  difftool: remove explicit change of PATH
  difftool: exit(0) when usage is printed
  difftool: add '--no-gui' option
  difftool: parse options using Getopt::Long
Merge branch 'jc/index-v4'

Trivially shrinks the on-disk size of the index file to save both I/O and
checksum overhead.

The topic should give a solid base to build on further updates, with the
code refactoring in its earlier parts, and the backward compatibility
mechanism in its later parts.

* jc/index-v4:
  index-v4: document the entry format
  unpack-trees: preserve the index file version of original
  update-index: upgrade/downgrade on-disk index version
  read-cache.c: write prefix-compressed names in the index
  read-cache.c: read prefix-compressed names in index on-disk version v4
  read-cache.c: move code to copy incore to ondisk cache to a helper function
  read-cache.c: move code to copy ondisk to incore cache to a helper function
  read-cache.c: report the header version we do not understand
  read-cache.c: make create_from_disk() report number of bytes it consumed
  read-cache.c: allow unaligned mapping of the index file
  cache.h: hide on-disk index details
  varint: make it available outside the context of pack
Merge branch 'mm/simple-push'

New users tend to work on one branch at a time and push the result
out. The current and upstream modes of push is a more suitable default
mode than matching mode for these people, but neither is surprise-free
depending on how the project is set up. Introduce a "simple" mode that
is a subset of "upstream" but only works when the branch is named the same
between the remote and local repositories.

The plan is to make it the new default when push.default is not
configured.

By Matthieu Moy (5) and others
* mm/simple-push:
  push.default doc: explain simple after upstream
  push: document the future default change for push.default (matching -> simple)
  t5570: use explicit push refspec
  push: introduce new push.default mode "simple"
  t5528-push-default.sh: add helper functions
  Undocument deprecated alias 'push.default=tracking'
  Documentation: explain push.default option a bit more
Merge branch 'nd/i18n'

More message strings marked for i18n.

By Nguyễn Thái Ngọc Duy (10) and Jonathan Nieder (1)
* nd/i18n:
  help: replace underlining "help -a" headers using hyphens with a blank line
  i18n: bundle: mark strings for translation
  i18n: index-pack: mark strings for translation
  i18n: apply: update say_patch_name to give translators complete sentence
  i18n: apply: mark strings for translation
  i18n: remote: mark strings for translation
  i18n: make warn_dangling_symref() automatically append \n
  i18n: help: mark strings for translation
  i18n: mark relative dates for translation
  strbuf: convenience format functions with \n automatically appended
  Makefile: feed all header files to xgettext
Merge branch 'jk/doc-asciidoc-inline-literal'

Our documentation was written for an ancient version of AsciiDoc,
making the source not very readable.

By Jeff King
* jk/doc-asciidoc-inline-literal:
  docs: stop using asciidoc no-inline-literal
Merge branch 'zj/mksh-columns-breakage'

A broken shell may not let us set an environment value to an arbitrary
value, interfering with some of the tests. Introduce a test prerequisite
so that we can skip some tests on such a platform.

By Zbigniew Jędrzejewski-Szmek
* zj/mksh-columns-breakage:
  test-lib: skip test with COLUMNS=1 under mksh
Merge branch 'lp/diffstat-with-graph'

"log --graph" was not very friendly with "--stat" option and its output
had line breaks at wrong places.

By Lucian Poston (5) and Zbigniew Jędrzejewski-Szmek (2)
* lp/diffstat-with-graph:
  t4052: work around shells unable to set COLUMNS to 1
  Prevent graph_width of stat width from falling below min
  t4052: Test diff-stat output with minimum columns
  t4052: Adjust --graph --stat output for prefixes
  Adjust stat width calculations to take --graph output into account
  Add output_prefix_length to diff_options
  t4052: test --stat output with --graph