t4034: abstract away SHA-1-specific constants

[thirdparty/git.git] / Documentation / git-rebase.txt

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 6156609cf7149ccf5c1f79df2d9807cdbcc609ba..639a4179d18e4d154f30351aaa4f3b3c79c48c1e 100644 (file)
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -8,8 +8,8 @@ git-rebase - Reapply commits on top of another base tip
 SYNOPSIS
 --------
 [verse]
-'git rebase' [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
-       [<upstream> [<branch>]]
+'git rebase' [-i | --interactive] [<options>] [--exec <cmd>]
+       [--onto <newbase> | --keep-base] [<upstream> [<branch>]]
 'git rebase' [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
        --root [<branch>]
 'git rebase' (--continue | --skip | --abort | --quit | --edit-todo | --show-current-patch)
@@ -217,6 +217,24 @@ As a special case, you may use "A\...B" as a shortcut for the
 merge base of A and B if there is exactly one merge base. You can
 leave out at most one of A and B, in which case it defaults to HEAD.
 
+--keep-base::
+       Set the starting point at which to create the new commits to the
+       merge base of <upstream> <branch>. Running
+       'git rebase --keep-base <upstream> <branch>' is equivalent to
+       running 'git rebase --onto <upstream>... <upstream>'.
++
+This option is useful in the case where one is developing a feature on
+top of an upstream branch. While the feature is being worked on, the
+upstream branch may advance and it may not be the best idea to keep
+rebasing on top of the upstream but to keep the base commit as-is.
++
+Although both this option and --fork-point find the merge base between
+<upstream> and <branch>, this option uses the merge base as the _starting
+point_ on which new commits will be created, whereas --fork-point uses
+the merge base to determine the _set of commits_ which will be rebased.
++
+See also INCOMPATIBLE OPTIONS below.
+
 <upstream>::
        Upstream branch to compare against.  May be any valid commit,
        not just an existing branch name. Defaults to the configured
@@ -369,6 +387,10 @@ ends up being empty, the <upstream> will be used as a fallback.
 +
 If either <upstream> or --root is given on the command line, then the
 default is `--no-fork-point`, otherwise the default is `--fork-point`.
++
+If your branch was based on <upstream> but <upstream> was rewound and
+your branch contains commits which were dropped, this option can be used
+with `--keep-base` in order to drop those commits from your branch.
 
 --ignore-whitespace::
 --whitespace=<option>::
@@ -543,8 +565,8 @@ In addition, the following pairs of options are incompatible:
  * --preserve-merges and --interactive
  * --preserve-merges and --signoff
  * --preserve-merges and --rebase-merges
- * --rebase-merges and --strategy
- * --rebase-merges and --strategy-option
+ * --keep-base and --onto
+ * --keep-base and --root
 
 BEHAVIORAL DIFFERENCES
 -----------------------
@@ -832,7 +854,8 @@ Hard case: The changes are not the same.::
        This happens if the 'subsystem' rebase had conflicts, or used
        `--interactive` to omit, edit, squash, or fixup commits; or
        if the upstream used one of `commit --amend`, `reset`, or
-       `filter-branch`.
+       a full history rewriting command like
+       https://github.com/newren/git-filter-repo[`filter-repo`].
 
 
 The easy case
@@ -870,7 +893,7 @@ NOTE: While an "easy case recovery" sometimes appears to be successful
       --interactive` will be **resurrected**!
 
 The idea is to manually tell 'git rebase' "where the old 'subsystem'
-ended and your 'topic' began", that is, what the old merge-base
+ended and your 'topic' began", that is, what the old merge base
 between them was.  You will have to find a way to name the last commit
 of the old 'subsystem', for example: