Hi Peff, On 20/09/2021 21:50, Jeff King wrote: > On Mon, Sep 20, 2021 at 12:40:21PM +0100, Philip Oakley wrote: > >> One thing that catches me, and I think others, is how the 'strategies' >> work. IIUC a merge will look at each line in the diff, and accept any >> change on either side that has no conflicts within the context zone. >> It's only when there are changes from both sides that the selection >> strategy kicks in. But it is difficult to describe, so it's easy to be >> confused. > I think you might be confusing the "ours" strategy (which takes the > tree state of the first parent entirely) with the "ours" (and "theirs") > options of the merge-recursive (or ort) strategy. > > You can see the difference with: > > git init repo > cd repo > > echo base >file > git add file > git commit -m base > > echo main >file > git add file > git commit -m main > > git checkout -b side HEAD^ > echo side >file > echo unrelated >another > git add file another > git commit -m side > > git checkout -b strategy-ours main > git merge -s ours side > > git checkout -b option-ours main > git merge -X ours side > > The strategy-ours merge will drop "another", because it was not in the > first parent. Whereas option-ours will keep it, preferring the > first parent only for the conflict in "file". > > You could construct a similar example where instead of a second file, > there's enough content in "file" that some of it does not conflict. > > -Peff Thanks for the clarification. I was probably over thinking the problem, by starting at the default and adding conditions that are extras to that, rather than reducing the conditions! The `theirs` strategy is really only suitable for maintainers, rather than solo coders, as it need to be 'old releases` that are kept, rather 'old cruft` (I've generated too much of that in my time). Dscho's scripts (for anyone interested) for GfW are in https://github.com/git-for-windows/build-extra/blob/main/shears.sh#L16-L18 and https://github.com/git-for-windows/build-extra/blob/main/ever-green.sh, though from the script perspective it's an 'ours' strategy. Dscho has to locate the start commit via it's subject line, rather than it's topology. -- Philip
