Python 3.12 in pipelines

.github/workflows/main.yml

@@ -28,7 +28,7 @@ jobs:
     strategy:
       matrix:
         os: [Ubuntu, macOS, Windows]
-        python-version: ["3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12-dev"]
         include:
           - os: Ubuntu
             image: ubuntu-22.04
@@ -117,7 +117,8 @@ jobs:
           ref: refs/tags/${{ steps.poetry-plugin-export-version.outputs.version }}
 
       - name: Run pytest (poetry-plugin-export)
-        run: poetry run pytest -v poetry-plugin-export/tests/
+        working-directory: ./poetry-plugin-export
+        run: poetry run -C .. pytest -v
 
       - name: Check for clean working tree
         run: |

docs/configuration.md

@@ -375,6 +375,12 @@ If set to `true` the `--no-setuptools` parameter is passed to `virtualenv` on cr
 means when a new virtual environment is created, `setuptools` will not be installed in the environment. Poetry, for its
 internal operations, does not require `setuptools` and this can safely be set to `true`.
 
+For environments using python 3.12 or later, `virtualenv` defaults to not
+installing `setuptools` when creating a virtual environment.
+In such environments this poetry configuration option therefore has no effect:
+`setuptools` is not installed either way.
+If your project relies on `setuptools`, you should declare it as a dependency.
+
 {{% warning %}}
 Some development tools like IDEs, make an assumption that `setuptools` (and other) packages are always present and
 available within a virtual environment. This can cause some features in these tools to not work as expected.

pyproject.toml

@@ -57,7 +57,7 @@ tomli = { version = "^2.0.1", python = "<3.11" }
 tomlkit = ">=0.11.4,<1.0.0"
 # trove-classifiers uses calver, so version is unclamped
 trove-classifiers = ">=2022.5.19"
-virtualenv = "^20.22.0"
+virtualenv = "^20.23.0"
 xattr = { version = "^0.10.0", markers = "sys_platform == 'darwin'" }
 
 [tool.poetry.group.dev.dependencies]

tests/utils/test_env.py

@@ -1513,6 +1513,14 @@ def test_env_no_pip(
         if package.name != "sqlite3"
     }
 
+    # For python >= 3.12, virtualenv defaults to "--no-setuptools" and "--no-wheel"
+    # behaviour, so setting these values to False becomes meaningless.
+    if sys.version_info >= (3, 12):
+        if not flags.get("no-setuptools", True):
+            packages.discard("setuptools")
+        if not flags.get("no-wheel", True):
+            packages.discard("wheel")
+
     assert installed_packages == packages