Re: VC mode and git

[Stephen J. Turnbull]

Eli Zaretskii writes:
 > > From: Sergey Organov <address@hidden>

 > > Each commit has zero or more pointers to parents, usually 1. Merge
 > > commit is commit that has more pointers to parents than 1 (usually 2).
 > > That's all about the meta-data. Simple, eh?
 > 
 > And that meta-data needs to be brought in as part of the merge, in
 > addition to changes to the tree.

No.  That's an important difference between git and other DVCSes.
"git merge" does a 3-way merge in a tree that corresponds to a
previously committed state, and sets up some (hidden) metadata that
help automate the following multi-parent commit.  Optionally it will
initiate that commit.

The meta-data must already be present in the repo pointed to by the
workspace, brought in by a fetch.  Because it's a very common
operation, especially in synchronizing mirror repos, git pull will
automatically fetch and merge.  Perhaps that what you think about it.

 > You can call all of this a "commit", but then you probably mean
 > "commit object", a different beast.  Using confusing shorts in this
 > discussion doesn't help understanding.

In discussing git, claiming that "commit" is anything other than a
verb that means "to create a commit object" is what confuses
understanding.  You will confuse those who are familiar with git and
give incorrect ideas to those who aren't.  If you have a different
concept of what a commit "should be", you need to explain that, and
what sequence of git operations correspond to that concept.