view tests/test-update-reverse.t @ 37271:0194dac77c93

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

  $ hg init

  $ touch a
  $ hg add a
  $ hg commit -m "Added a"

  $ touch main
  $ hg add main
  $ hg commit -m "Added main"
  $ hg checkout 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

'main' should be gone:

  $ ls
  a

  $ touch side1
  $ hg add side1
  $ hg commit -m "Added side1"
  created new head
  $ touch side2
  $ hg add side2
  $ hg commit -m "Added side2"

  $ hg log
  changeset:   3:91ebc10ed028
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side2
  
  changeset:   2:b932d7dbb1e1
  parent:      0:c2eda428b523
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side1
  
  changeset:   1:71a760306caf
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added main
  
  changeset:   0:c2eda428b523
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added a
  

  $ hg heads
  changeset:   3:91ebc10ed028
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side2
  
  changeset:   1:71a760306caf
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added main
  
  $ ls
  a
  side1
  side2

  $ hg update --debug -C 1
  resolving manifests
   branchmerge: False, force: True, partial: False
   ancestor: 91ebc10ed028+, local: 91ebc10ed028+, remote: 71a760306caf
   side1: other deleted -> r
  removing side1
   side2: other deleted -> r
  removing side2
   main: remote created -> g
  getting main
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ ls
  a
  main