[petsc-dev] how do people manage projects that require two or more PETSc branches

[Satish Balay]

On Sat, 17 Apr 2021, Barry Smith wrote:

> 
>    Say I have a project (a code whose source is not in the PETSc repository) that requires code from two PETSc branches (that may or may not yet be MR) but I do not want to make a single PETSc branch (since it would be incoherent).

The primary issue is managing the dependencies between changes (commits, features). And when making a new change - (for each new change) evaluate and update, reorder the prior commits as needed.

Attempting to avoid this usually results in a bad commit history - and I've been trying to avoid in petsc history. [currently a single merge commit - which is not cohesive - or easily debuggable is what I'm falling back on]

Any work-flow below won't be able to mask the above problem easily.

If the above problem is managed (requires constant rebasing/collapsing/rerordering/moving-commits etc] - then the workflow below is just book-keeping.. [one can aswell use a single branch  and split into 2 branches when the features are complete]

Satish


> I may possibly be needing to add code to both of the PETSc branches as I develop the project. I also need to do development sometimes on different machines.
> 
>    I can do 
> 
>       git checkout branch1
>       git checkout -b combinedbranch
>       git merge branch2 
>       configure
>       make
>       use for a while
> 
> but now I need to fix or add something to branch1 (which, of course, will be an iterative process as I write the code and fix it) and then add something in branch2. 
> 
> Doing the above procedure over and over again is tedious and prone to produce errors, editing in the wrong branch etc.
> 
> Does anyone have advice on good work flows for this situation?
> 
> Barry
>