Method run_update

copier/_main.py:1304–1353

Update a subproject that was already generated. See [updating a project][updating-a-project].

(self)

    @as_operation("update")
    def run_update(self) -> None:
        """Update a subproject that was already generated.

        See [updating a project][updating-a-project].
        """
        self._check_unsafe("update")
        # Check all you need is there
        if self.subproject.vcs != "git":
            raise UserMessageError(
                "Updating is only supported in git-tracked subprojects."
            )
        if self.subproject.is_dirty():
            raise UserMessageError(
                "Destination repository is dirty; cannot continue. "
                "Please commit or stash your local changes and retry."
            )
        if self.subproject.template is None or self.subproject.template.ref is None:
            raise UserMessageError(
                "Cannot update because cannot obtain old template references "
                f"from `{self.subproject.answers_relpath}`."
            )
        if self.template.commit is None:
            raise UserMessageError(
                "Updating is only supported in git-tracked templates."
            )
        if not self.subproject.template.version:
            raise UserMessageError(
                "Cannot update: version from last update not detected."
            )
        if not self.template.version:
            raise UserMessageError("Cannot update: version from template not detected.")
        if self.subproject.template.version > self.template.version:
            raise UserMessageError(
                f"You are downgrading from {self.subproject.template.version} to {self.template.version}. "
                "Downgrades are not supported."
            )
        if not self.overwrite:
            # Only git-tracked subprojects can be updated, so the user can
            # review the diff before committing; so we can safely avoid
            # asking for confirmation
            raise UserMessageError("Enable overwrite to update a subproject.")
        self._print_message(self.template.message_before_update)
        self._print_template_update_info(self.subproject.template)
        with suppress(AttributeError):
            # We might have switched operation context, ensure the cached property
            # is regenerated to re-render templates.
            del self.match_exclude

        self._apply_update()
        self._print_message(self.template.message_after_update)

    def _apply_update(self) -> None:  # noqa: C901
        git = get_git()