Vendor attrs to avoid unpickle issues #3179 #3192

We have vendored attrs only for its use in licensedcode.models.
With this, we avoid updates to the attrs library that would make
unpickling the license index fail.

Reported-by: Soim @soimkim
Reference: #3192
Reference: #3179
Signed-off-by: Philippe Ombredanne <pombredanne@nexb.com>

Author: pombredanne

requirements-dev.txt

@@ -29,3 +29,5 @@ tomli==2.0.1
 tqdm==4.64.0
 twine==4.0.1
 typing_extensions==4.3.0
+vendorize==0.3.0
+

setup-mini.cfg

@@ -130,6 +130,7 @@ testing =
     twine
     black
     isort
+    vendorize >= 0.3.0
 
 docs =
     Sphinx >= 3.3.1

setup.cfg

@@ -130,6 +130,7 @@ testing =
     twine
     black
     isort
+    vendorize >= 0.3.0
 
 docs =
     Sphinx >= 3.3.1

src/licensedcode/_vendor/__init__.py

@@ -0,0 +1,80 @@
+# SPDX-License-Identifier: MIT
+
+from __future__ import absolute_import, division, print_function
+
+import sys
+
+from functools import partial
+
+from . import converters, exceptions, filters, setters, validators
+from ._cmp import cmp_using
+from ._config import get_run_validators, set_run_validators
+from ._funcs import asdict, assoc, astuple, evolve, has, resolve_types
+from ._make import (
+    NOTHING,
+    Attribute,
+    Factory,
+    attrib,
+    attrs,
+    fields,
+    fields_dict,
+    make_class,
+    validate,
+)
+from ._version_info import VersionInfo
+
+
+__version__ = "21.4.0"
+__version_info__ = VersionInfo._from_version_string(__version__)
+
+__title__ = "attrs"
+__description__ = "Classes Without Boilerplate"
+__url__ = "https://www.attrs.org/"
+__uri__ = __url__
+__doc__ = __description__ + " <" + __uri__ + ">"
+
+__author__ = "Hynek Schlawack"
+__email__ = "hs@ox.cx"
+
+__license__ = "MIT"
+__copyright__ = "Copyright (c) 2015 Hynek Schlawack"
+
+
+s = attributes = attrs
+ib = attr = attrib
+dataclass = partial(attrs, auto_attribs=True)  # happy Easter ;)
+
+__all__ = [
+    "Attribute",
+    "Factory",
+    "NOTHING",
+    "asdict",
+    "assoc",
+    "astuple",
+    "attr",
+    "attrib",
+    "attributes",
+    "attrs",
+    "cmp_using",
+    "converters",
+    "evolve",
+    "exceptions",
+    "fields",
+    "fields_dict",
+    "filters",
+    "get_run_validators",
+    "has",
+    "ib",
+    "make_class",
+    "resolve_types",
+    "s",
+    "set_run_validators",
+    "setters",
+    "validate",
+    "validators",
+]
+
+if sys.version_info[:2] >= (3, 6):
+    from ._next_gen import define, field, frozen, mutable  # noqa: F401
+
+    __all__.extend(("define", "field", "frozen", "mutable"))