StopIteration raised every time

In /text/init.py
StopIteration gets raised every time

def _read(path, encoding="utf-8", comment=";;;"):
    """ Returns an iterator over the lines in the file at the given path,
        strippping comments and decoding each line to Unicode.
    """
    if path:
        if isinstance(path, str) and os.path.exists(path):
            # From file path.
            f = open(path, "r", encoding="utf-8")
        elif isinstance(path, str):
            # From string.
            f = path.splitlines()
        else:
            # From file or buffer.
            f = path
        for i, line in enumerate(f):
            line = line.strip(BOM_UTF8) if i == 0 and isinstance(line, str) else line
            line = line.strip()
            line = decode_utf8(line, encoding)
            if not line or (comment and line.startswith(comment)):
                continue
            yield line
    raise StopIteration

Start in /text/init.py and inspect the _read function across its path, string, and file-or-buffer inputs. Verify the iterator’s behavior after normal input is consumed; done means valid inputs can be read without an unexpected StopIteration, with any relevant existing tests passing.