scmutil: add method for looking up a context given a revision symbol changectx's constructor currently supports a mix if inputs: * integer revnums * binary nodeids * '.', 'tip', 'null' * stringified revnums * namespaced identifiers (e.g. bookmarks and tags) * hex nodeids * partial hex nodeids The first two are always internal [1]. The other five can be specified by the user. The third type ('.', 'tip', 'null') often comes from either the user or internal callers. We probably have some internal callers that pass hex nodeids too, perhaps even partial ones (histedit?). There are only a few callers that pass user-supplied strings: revsets.stringset, peer.lookup, webutil.changeidctx, and maybe one or two more. Supporting this mix of things in the constructor is convenient, but a bit strange, IMO. For example, if repo[node] is given a node that's not in the repo, it will first check if it's bookmark etc before raising an exception. Of course, the risk of it being a bookmark is extremely small, but it just feels ugly. Also, a problem with having this code in the constructor (whether it supports a mix of types or not) is that it's harder to override (I'd like to override it, and that's how this series started). This patch starts moving out the handling of user-supplied strings by introducing scmutil.revsymbol(). So far, that just checks that the input is indeed a string, and then delegates to repo[symbol]. The patch also calls it from revsets.stringset to prove that it works. [1] Well, you probably can enter a 20-byte binary nodeid on the command line, but I don't think we should care to preserve support for that. Differential Revision: https://phab.mercurial-scm.org/D3024

narrow: add trailing slash to dir earlier for debug{revlog,index,data} The treemanifest code internally uses trailing slashes on directories (except for the root directory, which is an empty string). We should make sure we pass in directories with trailing slashes when we work with the treemanifest code. For some reason, I seem to have decided to be nice to the callers instead in 49c583ca48c4 (treemanifest: add --dir option to debug{revlog,data,index}, 2015-04-12). Let's fix that and pay the cost of fixing up the directory name close close to where we get it from the user. Differential Revision: https://phab.mercurial-scm.org/D3032

addremove: remove dry_run, similarity from scmutil.addremove (API) Differential Revision: https://phab.mercurial-scm.org/D3000

histedit: make errror message translatable This is a follow up patch to https://phab.mercurial-scm.org/D2394 As suggested by Yuya, this patch makes the error message translatable Differential Revision: https://phab.mercurial-scm.org/D3031

context: drop support for changeid='' (API) Since the previous commit, there seem to be no users who pass '' to repo.__getitem__, so let's drop support for it. It may seem like a small cost to keep support for it, but I've spent time being confused by it twice already. Differential Revision: https://phab.mercurial-scm.org/D3021

subrepo: use repo['.'] instead of repo[''] The "state" value (a revision) passed to abstractsubrepo.phase() can be '' to represent the currently checked out revisions. Let's convert that to the more common '.'. I think this is the last of use of repo['.'] in core. Differential Revision: https://phab.mercurial-scm.org/D3019

children: use repo['.'] instead of repo[''] Differential Revision: https://phab.mercurial-scm.org/D3020

revset: drop support for '' as alias for '.' Not marked BC because I think support for using '' on the CLI was there by accident, and we don't seem to have documented it. Differential Revision: https://phab.mercurial-scm.org/D3018

tests: add test showing current parse of empty string symbol in revset We support e.g. parents(""), but I think that's by accident and I'll change it soon. Differential Revision: https://phab.mercurial-scm.org/D3017

clone: rename "rev" to "revs" since there can be many It was a little tricky in hg.clone(), since there was a local "revs" variable defined there, but "rev" was never used after "revs", so I just overwrote it. Note that clonewithshare() should also have its "rev" argument renamed to "revs", but I'll leave that to someone else. Differential Revision: https://phab.mercurial-scm.org/D3016