On 3/30/2021 4:11 PM, Junio C Hamano wrote: > "Derrick Stolee via GitGitGadget" <gitgitgadget@xxxxxxxxx> writes: > >> @@ repo-settings.c: void prepare_repo_settings(struct repository *r) >> + * Initialize this as off. >> + */ >> + r->settings.sparse_index = 0; >> -+ if (!repo_config_get_bool(r, "extensions.sparseindex", &value) && value) >> ++ if (!repo_config_get_bool(r, "index.sparse", &value) && value) >> + r->settings.sparse_index = 1; >> } > > It would be helpful to have a way for the repository owner to say > "Even if the version of Git may be capable of handling 'sdir' > extension, and my checkout uses sparse-cone settings, I do not want > to use it", and the other way around, i.e. "Even if my checkout > currently does not use sparse-cone settings, do use 'sdir' > extension". But for that, .sparse_index member may need to be > tristate (i.e. forbidden, enable-if-needed, use-even-unneeded)? I believe as presented, index.sparse=false will prevent the sdir extension from being used. If index.sparse=true, then it will only be used if sparse-checkout is enabled in cone mode. I don't see the value in using the 'sdir' extension when not using sparse-checkout in cone mode (and hence there are no sparse directory entries in the index). What am I missing? > We have a similar setting in index.version; I believe we always > auto-demote 3 down to 2 when extended flags are not used, and > I think "always auto-demote" would be sufficient (iow, > "use-even-unneeded" may not be necessary, even though that might > help debugging). Yes, the same is happening here: we auto-demote to not use 'sdir' if it the other settings are not configured as well. There is the rare scenario where these things all occur: 1. index.sparse = true 2. core.sparseCheckout = true 3. core.sparseCheckoutCone = true 4. Every path in the index matches the cone-mode patterns. In this case, convert_to_sparse() is called and the istate->sparse bit is set, telling do_write_index() to add the 'sdir' extension. This seems like a rare occurrence. Is it still worth adding logic to avoid 'sdir' when these are all true? Thanks, -Stolee
