nodemap: keep track of the docket for loaded data To perform incremental update of the on disk data, we need to keep tracks of some aspect of that data. Differential Revision: https://phab.mercurial-scm.org/D7885

nodemap: introduce an explicit class/object for the docket We are about to add more information to this docket, having a clear location to stock them in memory will help. Differential Revision: https://phab.mercurial-scm.org/D7884

nodemap: keep track of the ondisk id of nodemap blocks If we are to incrementally update the files, we need to keep some details about the data we read. Differential Revision: https://phab.mercurial-scm.org/D7883

nodemap: provide the on disk data to indexes who support it Time to start defining the API and prepare the rust index support. We provide a method to do so. We use a distinct method instead of passing them in the constructor because we will need this method anyway later (to refresh the mmap once we update the data on disk). Differential Revision: https://phab.mercurial-scm.org/D7847

nodemap: all check that revision and nodes match in the nodemap More check is always useful. Differential Revision: https://phab.mercurial-scm.org/D7846

nodemap: add basic checking of the on disk nodemap content The simplest check it so verify we have all the revision we needs, and nothing more. Differential Revision: https://phab.mercurial-scm.org/D7845