Enhancement: Pydantic v2 Package Shim Compatibility (#55)

* Implements `compatibility` subpackage for easier version compatibility maintenance
* Adds Pydantic v1 / Pydantic v2 compatibility via shim
* Adds Pydantic v1 / Pydantic v2 to testing CI matrix
* Updates examples and adds compatibility notice

.github/workflows/tests.yml

@@ -17,6 +17,7 @@ jobs:
       matrix:
         os: [ "ubuntu-latest", "macos-13", "windows-latest" ]
         python-version: [ "3.8", "3.9", "3.10", "3.11", "3.12" ]
+        pydantic-version: [ "1.0", "2.0" ]
       fail-fast: false
     defaults:
       run:
@@ -34,9 +35,11 @@ jobs:
         uses: actions/cache@v4
         with:
           path: .venv
-          key: venv-${{ runner.os }}-${{ matrix.python-version }}-${{ hashFiles('pyproject.toml') }}
+          key: venv-${{ runner.os }}-${{ matrix.python-version }}-${{ matrix.pydantic-version }}-${{ hashFiles('pyproject.toml') }}
       - name: Install Hatch
         run: pip install git+https://github.com/pypa/hatch.git@master
+      - name: Install Pydantic
+        run: hatch run uv pip install pydantic~=${{ matrix.pydantic-version }}
       - name: Run Build Hooks
         run: hatch build --hooks-only
       - name: Run Tests
@@ -45,7 +48,7 @@ jobs:
         uses: coverallsapp/github-action@v2
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
-          flag-name: ${{ matrix.os }}-${{ matrix.python-version }}
+          flag-name: ${{ matrix.os }}-${{ matrix.python-version }}-${{ matrix.pydantic-version }}
           parallel: true
 
   coverage:

README.md

@@ -38,6 +38,9 @@
 ## Help
 See [documentation](https://pydantic-argparse.supimdos.com) for help.
 
+## Requirements
+Requires Python 3.8+, and is compatible with the Pydantic v1 API.
+
 ## Installation
 Installation with `pip` is simple:
 ```console
@@ -46,7 +49,7 @@ $ pip install pydantic-argparse
 
 ## Example
 ```py
-import pydantic
+import pydantic.v1 as pydantic
 import pydantic_argparse
 
 

docs/index.md

@@ -41,7 +41,8 @@
 provides declarative *typed* argument parsing using `pydantic` models.
 
 ## Requirements
-`pydantic-argparse` requires Python 3.8+
+`pydantic-argparse` requires Python 3.8+, and is compatible with the Pydantic
+v1 API.
 
 ## Installation
 Installation with `pip` is simple:

docs/showcase.md

@@ -7,7 +7,7 @@ The `pydantic-argparse` command-line interface construction is simple.
 
 === "Pydantic Argparse"
     ```python
-    import pydantic
+    import pydantic.v1 as pydantic
     import pydantic_argparse
 
     # Declare Arguments

examples/commands.py

@@ -2,7 +2,7 @@
 
 
 # Third-Party
-import pydantic
+import pydantic.v1 as pydantic
 import pydantic_argparse
 
 # Typing

examples/simple.py

@@ -2,7 +2,7 @@
 
 
 # Third-Party
-import pydantic
+import pydantic.v1 as pydantic
 import pydantic_argparse
 
 

pyproject.toml

@@ -9,7 +9,7 @@ authors = [{ name = "Hayden Richards", email = "[email protected]" }]
 readme = "README.md"
 license = { file = "LICENSE" }
 requires-python = ">=3.8"
-dependencies = ["pydantic<2"]
+dependencies = ["pydantic"]
 classifiers = [
     "Development Status :: 4 - Beta",
     'Programming Language :: Python',
@@ -102,7 +102,7 @@ warn_return_any = true
 warn_unused_ignores = true
 no_implicit_optional = true
 show_error_codes = true
-plugins = ["pydantic.mypy"]
+plugins = ["pydantic.v1.mypy"]
 
 [tool.pydantic-mypy]
 init_forbid_extra = true

src/pydantic_argparse/argparse/actions.py

@@ -7,8 +7,8 @@
 """
 
 
-# Standard
-import argparse
+# Local
+from pydantic_argparse.compatibility import argparse
 
 # Typing
 from typing import Any, Callable, Iterable, List, Optional, Sequence, Tuple, TypeVar, Union, cast

src/pydantic_argparse/argparse/parser.py

@@ -16,17 +16,14 @@
 
 
 # Standard
-import argparse
 import sys
 
-# Third-Party
-import pydantic
-
 # Local
 from pydantic_argparse import parsers
 from pydantic_argparse import utils
 from pydantic_argparse.argparse import actions
-from pydantic_argparse.argparse import patches  # noqa: F401
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Any, Dict, Generic, List, NoReturn, Optional, Type, TypeVar

src/pydantic_argparse/compatibility/__init__.py

@@ -0,0 +1,11 @@
+"""Compatibiltity Shims for Declarative Typed Argument Parsing.
+
+This package contains compatibility shims for the `pydantic` and `argparse`
+modules, so that we can properly maintain version compatibility in one place.
+
+The public interface exposed by this package is the module shims themselves.
+"""
+
+# Local
+from pydantic_argparse.compatibility.argparse import argparse as argparse
+from pydantic_argparse.compatibility.pydantic import pydantic as pydantic

src/pydantic_argparse/argparse/patches.py → src/pydantic_argparse/compatibility/argparse.py

@@ -1,4 +1,4 @@
-"""Monkey patches for ArgumentParser.
+"""Compatibility Shim for ArgumentParser.
 
 In order to support Python 3.8 while retaining the unit tests, we need to
 backport the bugfix for [`BPO-29298`](https://bugs.python.org/issue29298).

src/pydantic_argparse/compatibility/pydantic.py

@@ -0,0 +1,19 @@
+"""Compatibility Shim for Pydantic.
+
+In order to support both Pydantic v1 and Pydantic v2, we need to make sure we
+import the module correctly:
+
+* For `pydantic~=2.0` there is a working `v1` module.
+* For `pydantic==1.10.15` there is a broken `v1` module (with no `fields`).
+* For `pydantic<1.10.14` there is no `v1` module.
+"""
+
+
+# Pydantic Shim
+# There is a bit of fiddling around here to accomodate for the cases outlined
+# above, as well as to keep the type-checker and language-server happy.
+try:  # pragma: no cover
+    from pydantic import v1 as pydantic
+    pydantic.fields  # noqa: B018
+except (ImportError, AttributeError):  # pragma: no cover
+    import pydantic  # type: ignore[no-redef]

src/pydantic_argparse/parsers/boolean.py

@@ -7,18 +7,14 @@
 """
 
 
-# Standard
-import argparse
-
-# Third-Party
-import pydantic
-
 # Typing
 from typing import Optional
 
 # Local
 from pydantic_argparse import utils
 from pydantic_argparse.argparse import actions
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 
 def should_parse(field: pydantic.fields.ModelField) -> bool:

src/pydantic_argparse/parsers/command.py

@@ -7,17 +7,13 @@
 """
 
 
-# Standard
-import argparse
-
-# Third-Party
-import pydantic
-
 # Typing
 from typing import Optional
 
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 
 def should_parse(field: pydantic.fields.ModelField) -> bool:

src/pydantic_argparse/parsers/container.py

@@ -8,18 +8,16 @@
 
 
 # Standard
-import argparse
 import collections.abc
 import enum
 
-# Third-Party
-import pydantic
-
 # Typing
 from typing import Optional
 
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 
 def should_parse(field: pydantic.fields.ModelField) -> bool:

src/pydantic_argparse/parsers/enum.py

@@ -8,14 +8,12 @@
 
 
 # Standard
-import argparse
 import enum
 
-# Third-Party
-import pydantic
-
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Optional, Type

src/pydantic_argparse/parsers/literal.py

@@ -7,14 +7,10 @@
 """
 
 
-# Standard
-import argparse
-
-# Third-Party
-import pydantic
-
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Optional, Literal, get_args

src/pydantic_argparse/parsers/mapping.py

@@ -8,18 +8,16 @@
 
 
 # Standard
-import argparse
 import ast
 import collections.abc
 
-# Third-Party
-import pydantic
-
 # Typing
 from typing import Optional
 
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 
 def should_parse(field: pydantic.fields.ModelField) -> bool:

src/pydantic_argparse/parsers/standard.py

@@ -9,17 +9,13 @@
 """
 
 
-# Standard
-import argparse
-
-# Third-Party
-import pydantic
-
 # Typing
 from typing import Optional
 
 # Local
 from pydantic_argparse import utils
+from pydantic_argparse.compatibility import argparse
+from pydantic_argparse.compatibility import pydantic
 
 
 def parse_field(

src/pydantic_argparse/utils/arguments.py

@@ -5,8 +5,8 @@
 """
 
 
-# Third-Party
-import pydantic
+# Local
+from pydantic_argparse.compatibility import pydantic
 
 
 def name(field: pydantic.fields.ModelField, invert: bool = False) -> str:

src/pydantic_argparse/utils/errors.py

@@ -5,8 +5,8 @@
 """
 
 
-# Third-Party
-import pydantic
+# Local
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Union

src/pydantic_argparse/utils/namespaces.py

@@ -5,8 +5,8 @@
 """
 
 
-# Standard
-import argparse
+# Local
+from pydantic_argparse.compatibility import argparse
 
 # Typing
 from typing import Any, Dict

src/pydantic_argparse/utils/pydantic.py

@@ -10,8 +10,8 @@
 # Standard
 import contextlib
 
-# Third-Party
-import pydantic
+# Local
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Any, Callable, Dict, Optional, Type, TypeVar, Union

src/pydantic_argparse/utils/types.py

@@ -5,8 +5,8 @@
 """
 
 
-# Third-Party
-import pydantic
+# Local
+from pydantic_argparse.compatibility import pydantic
 
 # Typing
 from typing import Any, Tuple, Union, get_origin

tests/argparse/test_actions.py

@@ -6,14 +6,12 @@ class by testing the expected nested namespace functionality.
 """
 
 
-# Standard
-import argparse
-
 # Third-Party
 import pytest
 
 # Local
 from pydantic_argparse.argparse import actions
+from pydantic_argparse.compatibility import argparse
 from tests import conftest as conf