When concluding a conflicted "git merge --squash", the command
failed to read SQUASH_MSG that was prepared by "git merge", and
showed only the "# Conflicts:" list of conflicted paths.

Place the contents from SQUASH_MSG at the beginning, just like we
show the commit log skeleton first when concluding a normal merge,
and then show the "# Conflicts:" list, to help the user write the
log message for the resulting commit.

Test by Junio C Hamano <gitster@pobox.com>.

Signed-off-by: Sven Strickroth <sven@cs-ware.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The add_to_alternates_file function blindly uses
hold_lock_file_for_append to copy the existing contents, and
then adds the new line to it. This has two minor problems:

  1. We might add duplicate entries, which are ugly and
     inefficient.

  2. We do not check that the file ends with a newline, in
     which case we would bogusly append to the final line.
     This is quite unlikely in practice, though, as we call
     this function only from git-clone, so presumably we are
     the only writers of the file (and we always add a
     newline).

Instead of using hold_lock_file_for_append, let's copy the
file line by line, which ensures all records are properly
terminated. If we see an extra line, we can simply abort the
update (there is no point in even copying the rest, as we
know that it would be identical to the original).

As a bonus, we also get rid of some calls to the
static-buffer mkpath and git_path functions.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The early part of this test is rather old, and does not
follow our usual style guidelines. In particular:

  - the tests liberally chdir, and expect out-of-test "cd"
    commands to return them to a sane state

  - test commands aren't indented at all

  - there are a lot of minor formatting nits, like the
    opening quote of the test block on the wrong line,
    spaces after ">", etc

This patch fixes the style issues, and uses a few helper
functions, along with subshells and "git -C", to avoid
changing the cwd of the main script.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Allow an asterisk as a substring (as opposed to the entirety) of
a path component for both side of a refspec, e.g.
"refs/heads/o*:refs/remotes/heads/i*".

* jk/refspec-parse-wildcard:
  refs: loosen restriction on wildcard "*" refspecs
  refs: cleanup comments regarding check_refname_component()

New userdiff pattern definition for fountain screenwriting markup
format.

* zb/userdiff-fountain:
  userdiff: add support for Fountain documents

In preparation for allowing different "backends" to store the refs
in a way different from the traditional "one ref per file in $GIT_DIR
or in a $GIT_DIR/packed-refs file" filesystem storage, reduce
direct filesystem access to ref-like things like CHERRY_PICK_HEAD
from scripts and programs.

* dt/refs-backend-preamble:
  git-stash: use update-ref --create-reflog instead of creating files
  update-ref and tag: add --create-reflog arg
  refs: add REF_FORCE_CREATE_REFLOG flag
  git-reflog: add exists command
  refs: new public ref function: safe_create_reflog
  refs: break out check for reflog autocreation
  refs.c: add err arguments to reflog functions

"sparse checkout" misbehaved for a path that is excluded from the
checkout when switching between branches that differ at the path.

* as/sparse-checkout-removal:
  unpack-trees: don't update files with CE_WT_REMOVE set

Teach "git log" and friends a new "--date=format:..." option to
format timestamps using system's strftime(3).

* jk/date-mode-format:
  strbuf: make strbuf_addftime more robust
  introduce "format" date-mode
  convert "enum date_mode" into a struct
  show-branch: use DATE_RELATIVE instead of magic number

* pt/am-tests:
  t3901: test git-am encoding conversion
  t3418: non-interactive rebase --continue with rerere enabled
  t4150: tests for am --[no-]scissors
  t4150: am with post-applypatch hook
  t4150: am with pre-applypatch hook
  t4150: am with applypatch-msg hook
  t4150: am --resolved fails if index has unmerged entries
  t4150: am --resolved fails if index has no changes
  t4150: am refuses patches when paused
  t4151: am --abort will keep dirty index intact
  t4150: am fails if index is dirty
  t4150: am.messageid really adds the message id

Optimize computation of untracked status indicator by bash prompt
script (in contrib/).

* sg/bash-prompt-untracked-optim:
  bash prompt: faster untracked status indicator with untracked directories
  bash prompt: test untracked files status indicator with untracked dirs