diff: Tests for "git diff -O"

Adapted from $gmane/236427 by Anders Waldenborg, "diff: Add
diff.orderfile configuration variable".

Signed-off-by: Anders Waldenborg <anders@0x63.nu>
Signed-off-by: Samuel Bronson <naesten@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff: Let "git diff -O" read orderfile from any file, failing when appropriate

The -O flag really shouldn't silently fail to do anything when given a
path that it can't read from.

However, it should be able to read from un-mappable files, such as
pipes/fifos, /dev/null (as we document in the next patch), or in
fact *any* empty file (SUSv3 says mmapping length 0 must fail, and
Linux does so since 2.6.12).

Note: "-O/dev/null" did have the right effect, since the existing
error handling essentially worked out to "silently ignore the
orderfile".

So lets toss all of that logic to get the file mmapped and just use
strbuf_read_file() instead, which gives us decent error handling
practically for free.

Signed-off-by: Samuel Bronson <naesten@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff: Add diff.orderfile configuration variable

diff.orderfile acts as a default for the -O command line option.

[sb: split up aw's original patch; reworked tests and docs]

[FIXME: Relative paths should presumably be interpreted relative to
repository root; how should this be accomplished?]

Signed-off-by: Anders Waldenborg <anders@0x63.nu>
Signed-off-by: Samuel Bronson <naesten@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
prune-packed: use strbuf to avoid having to worry about PATH_MAX

A/very/long/path/to/.git that becomes exactly PATH_MAX bytes long
after suffixed with /objects/??/??38-hex??, would have overflown
the on-stack pathname[] buffer.

Noticed-by:  Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'kb/fast-hashmap' (early part) into jch

* 'kb/fast-hashmap' (early part):
  Drop unnecessary #includes from test-hashmap
  Add test-hashmap to .gitignore
  read-cache.c: fix memory leaks caused by removed cache entries
  builtin/update-index.c: cleanup update_one
  fix 'git update-index --verbose --again' output
  remove old hash.[ch] implementation
  name-hash.c: remove cache entries instead of marking them CE_UNHASHED
  name-hash.c: use new hash map implementation for cache entries
  name-hash.c: remove unreferenced directory entries
  name-hash.c: use new hash map implementation for directories
  diffcore-rename.c: use new hash map implementation
  diffcore-rename.c: simplify finding exact renames
  diffcore-rename.c: move code around to prepare for the next patch
  buitin/describe.c: use new hash map implementation
  add a hashtable implementation that supports O(1) removal
  submodule: don't access the .gitmodules cache entry after removing it
Merge branch 'jk/name-pack-after-byte-representation' into jch

Two packfiles that contain the same set of objects have
traditionally been named identically, but that made repacking a
repository that is already fully packed without any cruft with a
different packing parameter cumbersome. Update the convention to
name the packfile after the bytestream representation of the data,
not after the set of objects in it.

* jk/name-pack-after-byte-representation:
  pack-objects doc: treat output filename as opaque
  pack-objects: name pack files after trailer hash
  sha1write: make buffer const-correct
Merge branch 'jc/push-refmap' into jch

Make "git push origin master" update the same ref that would be
updated by our 'master' when "git push origin" (no refspecs) is run
while the 'master' branch is checked out, which makes "git push"
more symmetric to "git fetch" and more usable for the triangular
workflow.

* jc/push-refmap:
  push: also use "upstream" mapping when pushing a single ref
  push: use remote.$name.push as a refmap
  builtin/push.c: use strbuf instead of manual allocation
Merge branch 'nd/negative-pathspec' into jch

Introduce "negative pathspec" magic, to allow "git log -- . ':!dir'" to
tell us "I am interested in everything but 'dir' directory".

* nd/negative-pathspec:
  pathspec.c: support adding prefix magic to a pathspec with mnemonic magic
  Support pathspec magic :(exclude) and its short form :!
  glossary-content.txt: rephrase magic signature part
Merge branch 'zk/difftool-counts' into jch

Show the total number of paths and the number of paths shown so far
when "git difftool" prompts to launch an external diff tool, which
would give users some sense of progress.

* zk/difftool-counts:
  diff.c: fix some recent whitespace style violations
  difftool: display the number of files in the diff queue in the prompt
Merge branch 'jk/pull-rebase-using-fork-point' into jch

* jk/pull-rebase-using-fork-point:
  rebase: use reflog to find common base with upstream
  pull: use merge-base --fork-point when appropriate
Merge branch 'jk/rev-parse-double-dashes' into jch

"git rev-parse <revs> -- <paths>" did not implement the usual
disambiguation rules the commands in the "git log" family used in
the same way.

* jk/rev-parse-double-dashes:
  rev-parse: be more careful with munging arguments
  rev-parse: correctly diagnose revision errors before "--"
Merge branch 'jk/cat-file-regression-fix' into jch

* jk/cat-file-regression-fix:
  cat-file: handle --batch format with missing type/size
  cat-file: pass expand_data to print_object_or_die
Merge branch 'tg/diff-no-index-refactor' into jch

"git diff ../else/where/A ../else/where/B" when ../else/where is
clearly outside the repository, and "git diff --no-index A B", do
not have to look at the index at all, but we used to read the index
unconditionally.

* tg/diff-no-index-refactor:
  diff: avoid some nesting
  diff: add test for --no-index executed outside repo
  diff: don't read index when --no-index is given
  diff: move no-index detection to builtin/diff.c
Merge branch 'fc/remote-helper-fixes' into jch

* fc/remote-helper-fixes:
  remote-hg: add tests for special filenames
  remote-hg: fix 'shared path' path
  remote-helpers: add extra safety checks
  remote-hg: avoid buggy strftime()
Merge branch 'cc/replace-object-info' into jch

read_sha1_file() that is the workhorse to read the contents given
an object name honoured object replacements, but there is no
corresponding mechanism to sha1_object_info() that is used to
obtain the metainfo (e.g. type & size) about the object, leading
callers to weird inconsistencies.

* cc/replace-object-info:
  Documentation/git-replace: describe --format option
  builtin/replace: unset read_replace_refs
  t6050: add tests for listing with --format
  builtin/replace: teach listing using short, medium or full formats
  sha1_file: perform object replacement in sha1_object_info_extended()
  t6050: show that git cat-file --batch fails with replace objects
  sha1_object_info_extended(): add an "unsigned flags" parameter
  sha1_file.c: add lookup_replace_object_extended() to pass flags
  replace_object: don't check read_replace_refs twice
  rename READ_SHA1_FILE_REPLACE flag to LOOKUP_REPLACE_OBJECT
Merge branch 'js/gnome-keyring' into jch

Style fix.

* js/gnome-keyring:
  contrib/git-credential-gnome-keyring.c: small stylistic cleanups
### 2.0
Merge branch 'jc/push-2.0-default-to-simple' into jch

* jc/push-2.0-default-to-simple:
  push: switch default from "matching" to "simple"

# Conflicts:
# 	Documentation/config.txt
# 	Documentation/git-push.txt
# 	builtin/push.c
Merge branch 'jn/add-2.0-u-A-sans-pathspec' into jch

* jn/add-2.0-u-A-sans-pathspec:
  git add: -u/-A now affects the entire working tree

# Conflicts:
# 	builtin/add.c
Merge branch 'jc/add-2.0-ignore-removal' into jch

Updated endgame for "git add <pathspec>" that defaults to "--all"
aka "--no-ignore-removal".

* jc/add-2.0-ignore-removal:
  git add <pathspec>... defaults to "-A"

# Conflicts:
# 	builtin/add.c