Empty string prefix is added as "."

[me-kell]

when registering or using registry records from an interface with prefix='' plone.registry.registry.forInterface and plone.registry.registry.forInterface add a dot . as prefix (see below).

The conditional not prefix.endswith(".") should be extended with and prefix != ""

i.e. if not prefix.endswith(".") and prefix != "":

    def forInterface(self, interface, check=True, omit=(), prefix=None,
                     factory=None):
        if prefix is None:
            prefix = interface.__identifier__

        if not prefix.endswith("."):    # <- if not prefix.endswith(".") and prefix != "":
            prefix += '.'

    ...

    def registerInterface(self, interface, omit=(), prefix=None):
        if prefix is None:
            prefix = interface.__identifier__

        if not prefix.endswith("."):    # <- if not prefix.endswith(".") and prefix != "":
            prefix += '.'
    ...