Merge branch 'cc/replace'

* cc/replace:
  t6050: check pushing something based on a replaced commit
  Documentation: add documentation for "git replace"
  Add git-replace to .gitignore
  builtin-replace: use "usage_msg_opt" to give better error messages
  parse-options: add new function "usage_msg_opt"
  builtin-replace: teach "git replace" to actually replace
  Add new "git replace" command
  environment: add global variable to disable replacement
  mktag: call "check_sha1_signature" with the replacement sha1
  replace_object: add a test case
  object: call "check_sha1_signature" with the replacement sha1
  sha1_file: add a "read_sha1_file_repl" function
  replace_object: add mechanism to replace objects found in "refs/replace/"
  refs: add a "for_each_replace_ref" function

1 files changed, 71 insertions, 0 deletions

diff --git a/Documentation/git-replace.txt b/Documentation/git-replace.txt
new file mode 100644
index 0000000000..915cb77b29
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+++ b/Documentation/git-replace.txt
@@ -0,0 +1,71 @@
+git-replace(1)
+==============
+
+NAME
+----
+git-replace - Create, list, delete refs to replace objects
+
+SYNOPSIS
+--------
+[verse]
+'git replace' [-f] <object> <replacement>
+'git replace' -d <object>...
+'git replace' -l [<pattern>]
+
+DESCRIPTION
+-----------
+Adds a 'replace' reference in `.git/refs/replace/`
+
+The name of the 'replace' reference is the SHA1 of the object that is
+replaced. The content of the replace reference is the SHA1 of the
+replacement object.
+
+Unless `-f` is given, the replace reference must not yet exist in
+`.git/refs/replace/` directory.
+
+OPTIONS
+-------
+-f::
+	If an existing replace ref for the same object exists, it will
+	be overwritten (instead of failing).
+
+-d::
+	Delete existing replace refs for the given objects.
+
+-l <pattern>::
+	List replace refs for objects that match the given pattern (or
+	all if no pattern is given).
+	Typing "git replace" without arguments, also lists all replace
+	refs.
+
+BUGS
+----
+Comparing blobs or trees that have been replaced with those that
+replace them will not work properly. And using 'git reset --hard' to
+go back to a replaced commit will move the branch to the replacement
+commit instead of the replaced commit.
+
+There may be other problems when using 'git rev-list' related to
+pending objects. And of course things may break if an object of one
+type is replaced by an object of another type (for example a blob
+replaced by a commit).
+
+SEE ALSO
+--------
+linkgit:git-tag[1]
+linkgit:git-branch[1]
+
+Author
+------
+Written by Christian Couder <chriscool@tuxfamily.org> and Junio C
+Hamano <gitster@pobox.com>, based on 'git tag' by Kristian Hogsberg
+<krh@redhat.com> and Carlos Rica <jasampler@gmail.com>.
+
+Documentation
+--------------
+Documentation by Christian Couder <chriscool@tuxfamily.org> and the
+git-list <git@vger.kernel.org>, based on 'git tag' documentation.
+
+GIT
+---
+Part of the linkgit:git[1] suite