Autogenerated HTML docs for v2.15.0-374-g5f995

1 files changed, 56 insertions, 11 deletions

diff --git a/git-merge-base.html b/git-merge-base.html
index 07001c3a6..503b84ea6 100644
--- a/git-merge-base.html
+++ b/git-merge-base.html
@@ -932,24 +932,69 @@ topic origin/master</code>, the history of remote-tracking branch
 history of this shape:</p></div>

 <div class="literalblock">

 <div class="content">

-<pre><code>                 o---B1

+<pre><code>                 o---B2

                 /

----o---o---B2--o---o---o---B (origin/master)

+---o---o---B1--o---o---o---B (origin/master)

         \

-         B3

+         B0

           \

-           Derived (topic)</code></pre>

+           D0---D1---D (topic)</code></pre>

 </div></div>

-<div class="paragraph"><p>where <code>origin/master</code> used to point at commits B3, B2, B1 and now it

+<div class="paragraph"><p>where <code>origin/master</code> used to point at commits B0, B1, B2 and now it

 points at B, and your <code>topic</code> branch was started on top of it back

-when <code>origin/master</code> was at B3. This mode uses the reflog of

-<code>origin/master</code> to find B3 as the fork point, so that the <code>topic</code>

-can be rebased on top of the updated <code>origin/master</code> by:</p></div>

+when <code>origin/master</code> was at B0, and you built three commits, D0, D1,

+and D, on top of it.  Imagine that you now want to rebase the work

+you did on the topic on top of the updated origin/master.</p></div>

+<div class="paragraph"><p>In such a case, <code>git merge-base origin/master topic</code> would return the

+parent of B0 in the above picture, but B0^..D is <strong>not</strong> the range of

+commits you would want to replay on top of B (it includes B0, which

+is not what you wrote; it is a commit the other side discarded when

+it moved its tip from B0 to B1).</p></div>

+<div class="paragraph"><p><code>git merge-base --fork-point origin/master topic</code> is designed to

+help in such a case.  It takes not only B but also B0, B1, and B2

+(i.e. old tips of the remote-tracking branches your repository&#8217;s

+reflog knows about) into account to see on which commit your topic

+branch was built and finds B0, allowing you to replay only the

+commits on your topic, excluding the commits the other side later

+discarded.</p></div>

+<div class="paragraph"><p>Hence</p></div>

 <div class="literalblock">

 <div class="content">

-<pre><code>$ fork_point=$(git merge-base --fork-point origin/master topic)

-$ git rebase --onto origin/master $fork_point topic</code></pre>

+<pre><code>$ fork_point=$(git merge-base --fork-point origin/master topic)</code></pre>

 </div></div>

+<div class="paragraph"><p>will find B0, and</p></div>

+<div class="literalblock">

+<div class="content">

+<pre><code>$ git rebase --onto origin/master $fork_point topic</code></pre>

+</div></div>

+<div class="paragraph"><p>will replay D0, D1 and D on top of B to create a new history of this

+shape:</p></div>

+<div class="literalblock">

+<div class="content">

+<pre><code>                 o---B2

+                /

+---o---o---B1--o---o---o---B (origin/master)

+        \                   \

+         B0                  D0'--D1'--D' (topic - updated)

+          \

+           D0---D1---D (topic - old)</code></pre>

+</div></div>

+<div class="paragraph"><p>A caveat is that older reflog entries in your repository may be

+expired by <code>git gc</code>.  If B0 no longer appears in the reflog of the

+remote-tracking branch <code>origin/master</code>, the <code>--fork-point</code> mode

+obviously cannot find it and fails, avoiding to give a random and

+useless result (such as the parent of B0, like the same command

+without the <code>--fork-point</code> option gives).</p></div>

+<div class="paragraph"><p>Also, the remote-tracking branch you use the <code>--fork-point</code> mode

+with must be the one your topic forked from its tip.  If you forked

+from an older commit than the tip, this mode would not find the fork

+point (imagine in the above sample history B0 did not exist,

+origin/master started at B1, moved to B2 and then B, and you forked

+your topic at origin/master^ when origin/master was B1; the shape of

+the history would be the same as above, without B0, and the parent

+of B1 is what <code>git merge-base origin/master topic</code> correctly finds,

+but the <code>--fork-point</code> mode will not, because it is not one of the

+commits that used to be at the tip of origin/master).</p></div>

 </div>

 </div>

 <div class="sect1">

@@ -970,7 +1015,7 @@ $ git rebase --onto origin/master $fork_point topic</code></pre>
 <div id="footnotes"><hr /></div>

 <div id="footer">

 <div id="footer-text">

-Last updated 2016-10-27 07:23:54 JST

+Last updated 2017-11-27 12:32:50 JST

 </div>

 </div>

 </body>