revlog: rename `newversionflags` to `new_header` This make it consistent with the previous changeset. Differential Revision: https://phab.mercurial-scm.org/D10597

revlog: rename `versionflags` to header The variable is named as such because it contains "version" information and "flags" information. However you mostly needs to know the code to understand the name which is not great. The fact that this is the very first four bytes in all revlog seems more relevant, so we rename the variable "header". Differential Revision: https://phab.mercurial-scm.org/D10596

revlog: move index reading logic in a dedicated method They are multiple motivation to do it: * The logic is complicated enough to deserver its own method. * We will need to reuse this once we put a docket in use. * This split the actual reading from the processing of the read data better. Differential Revision: https://phab.mercurial-scm.org/D10595

revlog: define the actual index and datafile at loading time This is just code movement, to make the code closer to where we actually use it and where it will be defined in the future. Differential Revision: https://phab.mercurial-scm.org/D10594

revlog: simplify a conditionnal in _enforceinlinesize This is a gratuitous change to make things a bit easier to read. Differential Revision: https://phab.mercurial-scm.org/D10593

revlog: drop `flush` parameter from `_peek_iscensored` This is not used anywhere. Differential Revision: https://phab.mercurial-scm.org/D10592

revlog: fix error message when data are missing The error message the message was not using the requested offset, but the adjusted offset to that read more data for improved caching. This resulted in confusing error message. Differential Revision: https://phab.mercurial-scm.org/D10591

revlog: rename `nodemap_file` to `_nodemap_file` Same reasoning as for `indexfile and datafile`, lets hide these implementation details. Differential Revision: https://phab.mercurial-scm.org/D10590

revlog: use revlog.display_id in error related to bad revisions Differential Revision: https://phab.mercurial-scm.org/D10589

revlog: use revlog.display_id in "revision too big" errors Differential Revision: https://phab.mercurial-scm.org/D10588

revlog: use revlog.display_id in censor related errors Differential Revision: https://phab.mercurial-scm.org/D10587

revlog: use revlog.display_id in integrity error Differential Revision: https://phab.mercurial-scm.org/D10586

revlog: use revlog.display_id in ambiguity errors Differential Revision: https://phab.mercurial-scm.org/D10585

revlog: use revlog.display_id for corruption error Differential Revision: https://phab.mercurial-scm.org/D10584

revlog: use revlog.display_id in format related errors Differential Revision: https://phab.mercurial-scm.org/D10583

revlog: use revlog.display_id in narrow error message Differential Revision: https://phab.mercurial-scm.org/D10582

revlog: use revlog.display_id in LookupError Differential Revision: https://phab.mercurial-scm.org/D10581

revlog: use revlog.display_id for FilteredLookupError Differential Revision: https://phab.mercurial-scm.org/D10580

revlog: introduce a `display_id` property We currently using the "index file" to identify a revlog in error output. Since we are about to make the "index file" location more volatile, we need something better. We move to use the "radix", as it is close to what we currently use. We could probably do better, as pointed out in the comment, however that would be a quite detour from my current goal. Differential Revision: https://phab.mercurial-scm.org/D10579

revlog: also use radix when computing nodemap data file We have a radix, lets use it! Differential Revision: https://phab.mercurial-scm.org/D10578

revlog: stop usage of `_indexfile` to computing nodemap path We now have the radix explicitely lets use the radix explicitely Differential Revision: https://phab.mercurial-scm.org/D10577

revlog: use a "radix" to address revlog Instead of pointing to the index directly and to derive the other file from that, we directly provide the radix and let the revlog determine the associated file path internally. This is more robust and will give us more flexibility for picking this file name in the future. Differential Revision: https://phab.mercurial-scm.org/D10576

revlog: rename `datafile` to `datafile` We want to make the actual location of the datafile and location more of an implementation details than what is is currently. In that process, we make the attribute private. Differential Revision: https://phab.mercurial-scm.org/D10575

revlog: rename `indexfile` to `_indexfile` We want to make the actual location of the indexfile and location more of an implementation details than what is is currently. In that process, we make the attribute private. Differential Revision: https://phab.mercurial-scm.org/D10574

filelog: drop `indexfile` from `filelog` Since `filelog` objects are not revlog (no really, they are not…) we drop the revlog specific attribute. We need to directly access the underlying revlog in a couple of place that already assume that we have a revlog here. This is motivated by future change to that revlog attribute. Differential Revision: https://phab.mercurial-scm.org/D10573

manifest: drop the `indexfile` from `manifestrevlog` Since `manifestrevlog` object are not revlog (no really, they are not…) we drop the revlog specific attribute. We need to directly access the underlying revlog in a couple of place that already assume that we have a revlog here. This is motivated by future change to that revlog attribute. Differential Revision: https://phab.mercurial-scm.org/D10572

revlog: deal with special "postfix" explicitely revlog usually use a straight forward '.i' and '.d' naming except for two cases "in-transaction" changelog, and censoring. Our goal is to let the revlog code deal with the internal of the file naming itself. To do so, we need to start dealing with these postfix explicitly. Differential Revision: https://phab.mercurial-scm.org/D10571

revlog: split the option initialisation in its own method The part of the code is huge, keeping it separated will keep the `_loadindex` method simpler and help keeping logic well insulated. Differential Revision: https://phab.mercurial-scm.org/D10570

revlog: always "append" full size tuple Same reasoning as the previous patch. Differential Revision: https://phab.mercurial-scm.org/D10569

revlog: make the index always return the same tuple It is simpler to manage the diferrence in on disk format in the internal index code itself and lets the rest of the code always handle the same object. This will become even more important when the data we store will be entirely different (for example the changelog does not need the "linkrev" field. We start with item reading, we will deal with item writing in the next changesets. Differential Revision: https://phab.mercurial-scm.org/D10568