localrepo: read requirements file in makelocalrepository() Previously, scmutil.readrequires() loaded the requirements file and validated its content against what was supported. Requirements translate to repository features and are critical to our plans to dynamically create local repository types. So, we must load them in makelocalrepository() before a repository instance is constructed. This commit moves the reading of the .hg/requires file to makelocalrepository(). Because scmutil.readrequires() was performing I/O and validation, we inlined the validation into localrepository.__init__ and removed scmutil.readrequires(). I plan to remove scmutil.readrequires() in a future commit (we can't do it now because statichttprepo uses it). Differential Revision: https://phab.mercurial-scm.org/D4568

localrepo: check for .hg/ directory in makelocalrepository() As part of this, we move the check to before .hg/hgrc is loaded, as it makes sense to check for the directory before attempting to open a file in it. Differential Revision: https://phab.mercurial-scm.org/D4567

localrepo: load extensions in makelocalrepository() Behavior does change subtly. First, we now load the hgrc before optionally setting up the vfs ward. That's fine: the vfs ward is for debugging and we know we won't hit it when reading .hg/hgrc. If the loaded extension were performing repo/vfs I/O, then we'd be worried. But extensions don't have access to the repo object that loaded them when they are loaded. Unless they are doing stack walking as part of module loading (which would be crazy), they shouldn't have access to the repo that incurred their load. Second, we now load extensions outside of the try..except IOError block. Previously, if loading an extension raised IOError, it would be silently ignored. I'm pretty sure the IOError is there for missing .hgrc files and should never have been ignored for issues loading extensions. I don't think this matters in reality because extension loading traps I/O errors. Differential Revision: https://phab.mercurial-scm.org/D4566