upgrade: report size of backing files, not internal storage size upgrade.py is the only consumer of filelog.index, which I'd like to eliminate from the file storage interface. This commit changes the upgrade code to report the storage size of files by looking at the size of the files backing its storage instead of looking at the index. I'm not convinced the approach in this patch will live very long because it is relying on low-level attributes like "opener" and "files," which may behave very differently on non-revlog storage. But the data is only used for reporting purposes and it does get us one step closer to eliminating "index." A side-effect of this change is we now report the size of the revlog index data - not just the revision data. I think this is more accurate. Differential Revision: https://phab.mercurial-scm.org/D4717

filelog: store filename directly on revlog instance This attribute is only used by LFS. It is used by one of the revlog flag processor functions, which gets an instance of the revlog - not the file storage type. So, it makes sense to store this attribute on the revlog instead of the filelog. With this change, I'm pretty confident that LFS is no longer directly accessing file storage interface members that are revlog centric. i.e. it gets us one step closer to eliminating revlog-centric APIs from the file storage interface! Differential Revision: https://phab.mercurial-scm.org/D4715

lfs: access revlog directly LFS is monkeypatching filelog.filelog and is then accessing various filelog attributes in the monkeypatched function. This is all fine. But some of the attributes being accessed by LFS are revlog centric and shouldn't be exposed on the file storage interface. This commit changes the monkeypatched functions to access proxied attributes on self._revlog instead of self. This should be safe to do because non-revlog repositories should not be using filelog instances: instead they should have a separate class to represent file storage. So it is reasonable for LFS to assume the _revlog attribute exists and points to a revlog. Differential Revision: https://phab.mercurial-scm.org/D4714

largefiles: automatically load largefiles extension when required (BC) This is very similar to what we just did for LFS but for largefiles. See recent commit messages for the rationale here. Differential Revision: https://phab.mercurial-scm.org/D4713

lfs: don't add extension to hgrc after clone or share (BC) Now that repository loading in core supports automatically loading the lfs extension when the "lfs" requirement is present, we no longer need to update the .hg/hgrc of newly-created repos to load the lfs extension! I'm marking this as BC because it is a change in behavior. But users should not notice unless they create an LFS repo with new Mercurial and then attempt to use it with an old versions that doesn't support automatic extension loading. Differential Revision: https://phab.mercurial-scm.org/D4712

localrepo: automatically load lfs extension when required (BC) If an unrecognized requirement is present (possibly due to an unloaded extension), the user will get an error message telling them to go to https://mercurial-scm.org/wiki/MissingRequirement for more info. And some requirements clearly map to known extensions shipped by Mercurial. This commit teaches repository loading to automatically map requirements to extensions. We implement support for loading the lfs extension when the "lfs" requirement is present. This behavior feels more user-friendly to me and I'm having trouble coming up with a compelling reason to not do it. The strongest argument I have against is that - strictly speaking - requirements are general repository features and there could be N providers of that feature. e.g. in the case of LFS, there could be another extension implementing LFS support. And the user would want to use this non-official extension rather than the built-in one. The way this patch implements things, the non-official extension could be missing and Mercurial would load the official lfs extension, leading to unexpected behavior. But this feels like a highly marginal use case to me and doesn't outweigh the user benefit of "it just works." If someone really wanted to e.g. use a custom LFS extension, they could prevent the built-in one from being loaded by either defining "extensions.lfs=/path/to/custom/extension" or "extensions.lfs=!", as the automatic extension loading only occurs if there is no config entry for that extension. Differential Revision: https://phab.mercurial-scm.org/D4711

lfs: add repository feature denoting the use of LFS Whether LFS is enabled seems like a useful feature to expose. This will also facilitate some future work around LFS feature compatibility. Differential Revision: https://phab.mercurial-scm.org/D4710

localrepo: define "features" on repository instances (API) There are a handful of attributes/methods on repository instances that describe the behavior of the repository. Furthermore, there is an unbound set of repository descriptors that we may wish to expose. For example, an extension may wish to add a descriptor and have monkeypatched functions look for the presence of an attribute before taking actions. This commit introduces a "features" mechanism to allow repositories to self-advertise an arbitrary set of strings that describe repository behavior or capabilities. We implement basic support for advertising a few features to give an idea of what I want to use this for. Differential Revision: https://phab.mercurial-scm.org/D4709

localrepo: support writing shared file (API) Now that we can create a shared repository via creation options, we can handle other special actions related to share at repo creation time as well. One of the things we do after creating a shared repository is write out a .hg/shared file containing the list of additional things to share. Of which only "bookmarks" is supported. We add a creation option to hold the set of additional items to share. If items are defined, we write out the .hg/shared file at repo creation time. As part of this, we no longer hold the repo lock when writing the file. I'm pretty sure we don't care about the tiny race condition window. I'm also pretty sure the reason we used the lock was because the vfs auditor on the repo instance complained otherwise. Since the repo creation code doesn't have an audited vfs, we don't need to appease it. Because we no longer need to tell the post share hook what items are shared, the "bookmarks" argument to that function has been dropped, incurring an API change. Differential Revision: https://phab.mercurial-scm.org/D4708

localrepo: support shared repo creation Previously, hg.share() had its own logic for creating a new repository on the filesystem. With the recent introduction of the createopts dict for passing options to influence repository creation, it is now possible to consolidate the repo creation code for both the normal and shared use cases. This commit teaches the repo creation code in localrepo to recognize when we're creating a shared repo and to act appropriately. Meaningful behavior should be identical. However, there are a few subtle changes: * The .hg/requires file is written out in sorted order (rather than having share-related requirements appended at end). * The .hg directory is created with notindexed=True when a shared repo is being created. Differential Revision: https://phab.mercurial-scm.org/D4707