[PATCH RFC STABLE] introduce new RequirementError (issue2649)

[Adrian Buehlmann]

On 2011-02-18 21:58, Adrian Buehlmann wrote:
> # HG changeset patch
> # User Adrian Buehlmann <adrian at cadifra.com>
> # Date 1298057125 -3600
> # Branch stable
> # Node ID eee8ff74d9d09f0da56db07c0799397839772ef1
> # Parent  d724a69309e0ce9a7d8efb13e11ba45a4c85045c
> introduce new RequirementError (issue2649)
> 
> We do not inherit from RepoError to make sure this error is not caught by
> "except error.RepoError" blocks like in dispatch.py line 581, so we can
> avoid obscuring the original error message, which explicitly mentions the
> unknown requirement ("requirement ... not supported").
> 
> RequirementError is a non-recoverable error.
> 
> diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
> --- a/mercurial/dispatch.py
> +++ b/mercurial/dispatch.py
> @@ -94,6 +94,8 @@ def _runcatch(ui, args):
>          else:
>              ui.warn(_("hg: %s\n") % inst.args[1])
>              commands.help_(ui, 'shortlist')
> +    except error.RequirementError, inst:
> +        ui.warn(_("abort: %s!\n") % inst)
>      except error.RepoError, inst:
>          ui.warn(_("abort: %s!\n") % inst)
>      except error.ResponseError, inst:
> diff --git a/mercurial/error.py b/mercurial/error.py
> --- a/mercurial/error.py
> +++ b/mercurial/error.py
> @@ -51,6 +51,11 @@ class RepoLookupError(RepoError):
>  class CapabilityError(RepoError):
>      pass
>  
> +class RequirementError(Exception):
> +    """Exception raised if .hg/requires has an unknown entry.
> +    Intentionally not inherited from RepoError"""
> +    pass
> +

I must say I'm not really sure about whether RequirementError should
inherit from RepoError or not.

Thus the RFC tag.

Iff it would inherit from RepoError, then something like


diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
--- a/mercurial/dispatch.py
+++ b/mercurial/dispatch.py
@@ -576,6 +576,8 @@ def _dispatch(ui, args):
             if not repo.local():
                 raise util.Abort(_("repository '%s' is not local") % path)
             ui.setconfig("bundle", "mainreporoot", repo.root)
+        except error.RequirementError:
+            raise
         except error.RepoError:
             if cmd not in commands.optionalrepo.split():
                 if args and not path: # try to infer -R from command args


for dispatch.py would be needed to make sure the RequirementError is not
sucked up by the "except error.RepoError" handler block.

>  class LockError(IOError):
>      def __init__(self, errno, strerror, filename, desc):
>          IOError.__init__(self, errno, strerror, filename)
> diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
> --- a/mercurial/localrepo.py
> +++ b/mercurial/localrepo.py
> @@ -75,7 +75,8 @@ class localrepository(repo.repository):
>                  if inst.errno != errno.ENOENT:
>                      raise
>              for r in requirements - self.supported:
> -                raise error.RepoError(_("requirement '%s' not supported") % r)
> +                raise error.RequirementError(
> +                          _("requirement '%s' not supported") % r)
>  
>          self.sharedpath = self.path
>          try:
> diff --git a/mercurial/statichttprepo.py b/mercurial/statichttprepo.py
> --- a/mercurial/statichttprepo.py
> +++ b/mercurial/statichttprepo.py
> @@ -112,7 +112,8 @@ class statichttprepository(localrepo.loc
>          # check them
>          for r in requirements:
>              if r not in self.supported:
> -                raise error.RepoError(_("requirement '%s' not supported") % r)
> +                raise error.RequirementError(
> +                        _("requirement '%s' not supported") % r)
>  
>          # setup store
>          self.store = store.store(requirements, self.path, opener)
> diff --git a/tests/test-commit.t b/tests/test-commit.t
> --- a/tests/test-commit.t
> +++ b/tests/test-commit.t
> @@ -92,6 +92,15 @@ An empty date was interpreted as epoch o
>    $ hg commit -d '' -m commit-no-date
>    $ hg tip --template '{date|isodate}\n' | grep '1970'
>    [1]
> +
> +Make sure we do not obscure unknown requires file entries (issue2649)
> +
> +  $ echo foo >> foo
> +  $ echo fake >> .hg/requires
> +  $ hg commit -m bla
> +  abort: requirement 'fake' not supported!
> +  [255]
> +
>    $ cd ..
>  
>  
> diff --git a/tests/test-identify.t b/tests/test-identify.t
> --- a/tests/test-identify.t
> +++ b/tests/test-identify.t
> @@ -67,3 +67,11 @@ remote with tags?
>    $ hg id -t http://localhost:$HGPORT1/
>    abort: can't query remote revision number, branch, or tags
>    [255]
> +
> +Make sure we do not obscure unknown requires file entries (issue2649)
> +
> +  $ echo fake >> .hg/requires
> +  $ hg id
> +  abort: requirement 'fake' not supported!
> +  [255]
> +