Method collect

src/_pytest/main.py:669–814

(self)

        return items

    def collect(self) -> Iterator[Union[nodes.Item, nodes.Collector]]:
        from _pytest.python import Package

        # Keep track of any collected nodes in here, so we don't duplicate fixtures.
        node_cache1: Dict[Path, Sequence[nodes.Collector]] = {}
        node_cache2: Dict[Tuple[Type[nodes.Collector], Path], nodes.Collector] = {}

        # Keep track of any collected collectors in matchnodes paths, so they
        # are not collected more than once.
        matchnodes_cache: Dict[Tuple[Type[nodes.Collector], str], CollectReport] = {}

        # Dirnames of pkgs with dunder-init files.
        pkg_roots: Dict[str, Package] = {}

        for argpath, names in self._initial_parts:
            self.trace("processing argument", (argpath, names))
            self.trace.root.indent += 1

            # Start with a Session root, and delve to argpath item (dir or file)
            # and stack all Packages found on the way.
            # No point in finding packages when collecting doctests.
            if not self.config.getoption("doctestmodules", False):
                pm = self.config.pluginmanager
                confcutdir = pm._confcutdir
                for parent in (argpath, *argpath.parents):
                    if confcutdir and parent in confcutdir.parents:
                        break

                    if parent.is_dir():
                        pkginit = parent / "__init__.py"
                        if pkginit.is_file() and pkginit not in node_cache1:
                            col = self._collectfile(pkginit, handle_dupes=False)
                            if col:
                                if isinstance(col[0], Package):
                                    pkg_roots[str(parent)] = col[0]
                                node_cache1[col[0].path] = [col[0]]

            # If it's a directory argument, recurse and look for any Subpackages.
            # Let the Package collector deal with subnodes, don't collect here.
            if argpath.is_dir():
                assert not names, f"invalid arg {(argpath, names)!r}"

                seen_dirs: Set[Path] = set()
                for direntry in visit(str(argpath), self._recurse):
                    if not direntry.is_file():
                        continue

                    path = Path(direntry.path)
                    dirpath = path.parent

                    if dirpath not in seen_dirs:
                        # Collect packages first.
                        seen_dirs.add(dirpath)
                        pkginit = dirpath / "__init__.py"
                        if pkginit.exists():
                            for x in self._collectfile(pkginit):
                                yield x
                                if isinstance(x, Package):