illustrate the differences between simplification settings. We assume
that you are filtering for a file `foo` in this commit graph:
-----------------------------------------------------------------------
- .-A---M---N---O---P
- / / / / /
- I B C D E
- \ / / / /
- `-------------'
+ .-A---M---N---O---P---Q
+ / / / / / /
+ I B C D E Y
+ \ / / / / /
+ `-------------' X
-----------------------------------------------------------------------
-The horizontal line of history A---P is taken to be the first parent of
+The horizontal line of history A---Q is taken to be the first parent of
each merge. The commits are:
* `I` is the initial commit, in which `foo` exists with contents
* `E` changes `quux` to "xyzzy", and its merge `P` combines the
strings to "quux xyzzy". `P` is TREESAME to `O`, but not to `E`.
+* `X` is an independent root commit that added a new file `side`, and `Y`
+ modified it. `Y` is TREESAME to `X`. Its merge `Q` added `side` to `P`, and
+ `Q` is TREESAME to `P`, but not to `Y`.
+
'rev-list' walks backwards through history, including or excluding
commits based on whether '\--full-history' and/or parent rewriting
(via '\--parents' or '\--children') are used. The following settings
the example, we get
+
-----------------------------------------------------------------------
- I A B N D O P
+ I A B N D O P Q
-----------------------------------------------------------------------
+
`M` was excluded because it is TREESAME to both parents. `E`,
themselves. This results in
+
-----------------------------------------------------------------------
- .-A---M---N---O---P
+ .-A---M---N---O---P---Q
/ / / / /
I B / D /
\ / / / /
Compare to '\--full-history' without rewriting above. Note that `E`
was pruned away because it is TREESAME, but the parent list of P was
rewritten to contain `E`'s parent `I`. The same happened for `C` and
-`N`.
+`N`, and `X`, `Y` and `Q`.
In addition to the above settings, you can change whether TREESAME
affects inclusion:
* Set `C'` to `C`.
+
* Replace each parent `P` of `C'` with its simplification `P'`. In
- the process, drop parents that are ancestors of other parents, and
- remove duplicates.
+ the process, drop parents that are ancestors of other parents or that are
+ root commits TREESAME to an empty tree, and remove duplicates, but take care
+ to never drop all parents that we are TREESAME to.
+
* If after this parent rewriting, `C'` is a root or merge commit (has
zero or >1 parents), a boundary commit, or !TREESAME, it remains.
`---------'
-----------------------------------------------------------------------
+
-Note the major differences in `N` and `P` over '--full-history':
+Note the major differences in `N`, `P` and `Q` over '--full-history':
+
--
* `N`'s parent list had `I` removed, because it is an ancestor of the
+
* `P`'s parent list similarly had `I` removed. `P` was then
removed completely, because it had one parent and is TREESAME.
++
+* `Q`'s parent list had `Y` simplified to `X`. `X` was then removed, because it
+ was a TREESAME root. `Q` was then removed completely, because it had one
+ parent and is TREESAME.
--
Finally, there is a fifth simplification mode available:
Show no parents before all of its children are shown, but
otherwise show commits in the commit timestamp order.
+--author-date-order::
+ Show no parents before all of its children are shown, but
+ otherwise show commits in the author timestamp order.
+
--topo-order::
Show no parents before all of its children are shown, and
avoid showing commits on multiple lines of history
-t::
Show the tree objects in the diff output. This implies '-r'.
-
--s::
- Suppress diff output.
endif::git-rev-list[]