[TOPIC 4/17] Sparse checkout

["James Ramsay" <james@jramsay.com.au>]

1. Stolee: built in! We’re making improvements! We’re looking at UX 
- add, remove, state. Harder things like grep needs everything, but not 
expected.

2. Elijah: we do have a strongly worded warning, so we could just change 
it.

3. Jonathan N: I like both modes.

4. Terry: how is GC wired up? If I change a cone, will it be reclaimed?

5. Stolee: GC doesn’t remove reachable objects. Haven’t found people 
need to do this, unless they accidentally rehydrated something massive 
they didn’t really need. Day to day work doesn’t introduce too much.

6. Terry: Android devs have massive special machines. Constantly running 
out of disk space.

7. Stolee: more of a partial clone feature, than a sparse checkout 
feature. If I checkout three branches, go offline, I don’t want GC to 
clean things that I had downloaded.

8. Jonathan N: switching between Word and Powerpoint. Would it be useful 
to attach cone to branch rather than repo.

9. Stolee: Office team is building some kind of magic to automatically 
detect from branch.

10. Brian: can use reflog maybe. Prune based on that? People who run out 
of disk space could have shorter reflog.

11. Elijah: biggest problem people run into doing a rebase/pull, hit 
conflicts, then they need to update sparsity patterns, which they 
can’t do because there are conflicts. Working on a patch.

12. Stolee: Office scoper tool would automatically recalculate 
dependencies and update sparsity config so that they can build.

13. During break, Minh brought up an idea that we could use in-tree data 
to manage the dependency chain: The tree could contain files that 
contain directory names, and users use config to specify the list of 
those files to use for the sparse-checkout definition. When Git updates 
the working directory and those files change, the sparse-checkout can be 
updated to include the union of those directories. Stolee will look into 
how this could work and whether this works for existing customers.