diff options
Diffstat (limited to 'src/buildstream/_loader/loadcontext.py')
| -rw-r--r-- | src/buildstream/_loader/loadcontext.py | 164 |
1 files changed, 134 insertions, 30 deletions
diff --git a/src/buildstream/_loader/loadcontext.py b/src/buildstream/_loader/loadcontext.py index 65b7e9157..c6d256050 100644 --- a/src/buildstream/_loader/loadcontext.py +++ b/src/buildstream/_loader/loadcontext.py @@ -21,6 +21,118 @@ from .._exceptions import LoadError from ..exceptions import LoadErrorReason +# ProjectLoaders() +# +# An object representing all of the loaders for a given project. +# +class ProjectLoaders: + def __init__(self, project_name): + + # The project name + self._name = project_name + + # A list of all loaded loaders for this project + self._collect = [] + + # register_loader() + # + # Register a Loader for this project + # + # Args: + # loader (Loader): The loader to register + # + def register_loader(self, loader): + assert loader.project.name == self._name + + self._collect.append(loader) + + # assert_loaders(): + # + # Asserts the validity of loaders for this project + # + # Raises: + # (LoadError): In case there is a CONFLICTING_JUNCTION error + # + def assert_loaders(self): + duplicates = {} + primary = [] + + for loader in self._collect: + duplicating = self._search_duplicates(loader) + if duplicating: + duplicates[loader] = duplicating + else: + primary.append(loader) + + if len(primary) > 1: + self._raise_conflict(duplicates) + + elif primary and duplicates: + self._raise_conflict(duplicates) + + # _search_duplicates() + # + # Searches this loader's ancestry for projects which mark this + # loader as a duplicate. + # + # Args: + # loader (Loader): The loader to search for duplicate markers of + # + # Returns: + # (list): A list of Loader objects who's project has marked + # this junction as a duplicate + # + def _search_duplicates(self, loader): + duplicates = [] + for parent in loader.ancestors(): + if parent.project.junction_is_duplicated(self._name, loader): + duplicates.append(parent) + return duplicates + + # _raise_conflict() + # + # Raises the LoadError indicating there was a conflict, this + # will list all of the instances in which the project has + # been loaded as the LoadError detail string + # + # Args: + # duplicates (dict): A table of duplicating Loaders, indexed + # by duplicated Loader + # + # Raises: + # (LoadError): In case there is a CONFLICTING_JUNCTION error + # + def _raise_conflict(self, duplicates): + lines = [self._loader_description(loader, duplicates) for loader in self._collect] + raise LoadError( + "Project '{}' was loaded in multiple contexts".format(self._name), + LoadErrorReason.CONFLICTING_JUNCTION, + detail="\n".join(lines), + ) + + # _loader_description() + # + # Args: + # loader (Loader): The loader to describe + # duplicates (dict): A table of duplicating Loaders, indexed + # by duplicated Loader + # + # Returns: + # (str): A string representing how this loader was loaded + # + def _loader_description(self, loader, duplicates): + + line = "{}\n".format(loader) + + # Mention projects which have marked this project as a duplicate + duplicating = duplicates.get(loader) + if duplicating: + for dup in duplicating: + line += " Duplicated by: {}\n".format(dup) + + return line + + # LoaderContext() # # An object to keep track of overall context during the load process. @@ -71,44 +183,36 @@ class LoadContext: def set_fetch_subprojects(self, fetch_subprojects): self.fetch_subprojects = fetch_subprojects + # assert_loaders() + # + # Asserts that there are no conflicting projects loaded. + # + # Raises: + # (LoadError): A CONFLICTING_JUNCTION LoadError in the case of a conflict + # + def assert_loaders(self): + for _, loaders in self._loaders.items(): + loaders.assert_loaders() + # register_loader() # # Registers a new loader in the load context, possibly - # raising an error in the case of a conflict + # raising an error in the case of a conflict. + # + # This must be called after a recursive load process has completed, + # and after the pipeline is resolved (which is to say that all related + # Plugin derived objects have been instantiated). # # Args: # loader (Loader): The Loader object to register into context # - # Raises: - # (LoadError): A CONFLICTING_JUNCTION LoadError in the case of a conflict - # def register_loader(self, loader): project = loader.project - existing_loader = self._loaders.get(project.name, None) - if existing_loader: + try: + project_loaders = self._loaders[project.name] + except KeyError: + project_loaders = ProjectLoaders(project.name) + self._loaders[project.name] = project_loaders - assert project.junction is not None - - if existing_loader.project.junction: - # The existing provenance can be None even if there is a junction, this - # can happen when specifying a full element path on the command line. - # - provenance_str = "" - if existing_loader.provenance: - provenance_str = ": {}".format(existing_loader.provenance) - - detail = "Project '{}' was already loaded by junction '{}'{}".format( - project.name, existing_loader.project.junction._get_full_name(), provenance_str - ) - else: - detail = "Project '{}' is also the toplevel project".format(project.name) - - raise LoadError( - "{}: Error loading project '{}' from junction: {}".format( - loader.provenance, project.name, project.junction._get_full_name() - ), - LoadErrorReason.CONFLICTING_JUNCTION, - detail=detail, - ) - self._loaders[project.name] = loader + project_loaders.register_loader(loader) |