[PATCH 30/32] read-cache: force split index mode with GIT_TEST_SPLIT_INDEX

This could be used to run the whole test suite with split indexes. Index splitting is carried out at random. git read-tree also resets the index and forces splitting at the next update. I had a lot of headaches with the test suite, which proves it exercises split index pretty good.

[PATCH 30/32] read-cache: force split index mode with GIT_TEST_SPLIT_INDEX

This could be used to run the whole test suite with split indexes. Index splitting is carried out at random. git read-tree also resets the index and forces splitting at the next update. I had a lot of headaches with the test suite, which proves it exercises split index pretty good.