Method _catch_revision_errors

alembic/script/base.py:204–247

(
        self,
        ancestor: Optional[str] = None,
        multiple_heads: Optional[str] = None,
        start: Optional[str] = None,
        end: Optional[str] = None,
        resolution: Optional[str] = None,
    )

    @contextmanager
    def _catch_revision_errors(
        self,
        ancestor: Optional[str] = None,
        multiple_heads: Optional[str] = None,
        start: Optional[str] = None,
        end: Optional[str] = None,
        resolution: Optional[str] = None,
    ) -> Iterator[None]:
        try:
            yield
        except revision.RangeNotAncestorError as rna:
            if start is None:
                start = cast(Any, rna.lower)
            if end is None:
                end = cast(Any, rna.upper)
            if not ancestor:
                ancestor = (
                    "Requested range %(start)s:%(end)s does not refer to "
                    "ancestor/descendant revisions along the same branch"
                )
            ancestor = ancestor % {"start": start, "end": end}
            raise util.CommandError(ancestor) from rna
        except revision.MultipleHeads as mh:
            if not multiple_heads:
                multiple_heads = (
                    "Multiple head revisions are present for given "
                    "argument '%(head_arg)s'; please "
                    "specify a specific target revision, "
                    "'<branchname>@%(head_arg)s' to "
                    "narrow to a specific head, or 'heads' for all heads"
                )
            multiple_heads = multiple_heads % {
                "head_arg": end or mh.argument,
                "heads": util.format_as_comma(mh.heads),
            }
            raise util.CommandError(multiple_heads) from mh
        except revision.ResolutionError as re:
            if resolution is None:
                resolution = "Can't locate revision identified by '%s'" % (
                    re.argument
                )
            raise util.CommandError(resolution) from re
        except revision.RevisionError as err:
            raise util.CommandError(err.args[0]) from err

    def walk_revisions(
        self, base: str = "base", head: str = "heads"