[Test] add "empty" test package with no configuration in config file

noxfile.py

@@ -40,10 +40,10 @@
 
 examples = "minimal-program", "pybind11-project", "nanobind-project"
 examples += "swig-project", "minimal"
-test_packages = "namespace-project-a", "namespace-project-b"
+test_packages = "empty-config", "namespace-project-a", "namespace-project-b"
 test_packages += "bare-c-module", "cmake-preset", "cmake-options"
 
-purity = {"namespace-project-b": True}
+purity = {"empty-config": True, "namespace-project-b": True}
 
 
 def get_platform():

test-packages/empty-config/README.md

@@ -0,0 +1,3 @@
+# Empty config
+
+No options beyond metadata in pyproject.toml.

test-packages/empty-config/pyproject.toml

@@ -0,0 +1,11 @@
+[project]
+name = "empty-config"
+readme = "README.md"
+requires-python = ">=3.7"
+license = { "file" = "LICENSE" }
+authors = [{ "name" = "Pieter P", "email" = "[email protected]" }]
+dynamic = ["version", "description"]
+
+[build-system]
+requires = ["py-build-cmake~=0.4.0a1.dev0"]
+build-backend = "py_build_cmake.build"

test-packages/empty-config/src/empty_config/__init__.py

@@ -0,0 +1,9 @@
+"""
+Empty config
+"""
+
+__version__ = "0.4.0a1.dev0"
+
+
+def add(a, b):
+    return a + b

test-packages/empty-config/tests/test_empty.py

@@ -0,0 +1,5 @@
+from empty_config import add
+
+
+def test_add():
+    assert add(1, 2) == 3

tests/expected_contents/empty-config/sdist.txt

@@ -0,0 +1,5 @@
+empty_config-{{version}}/LICENSE
+empty_config-{{version}}/PKG-INFO
+empty_config-{{version}}/README.md
+empty_config-{{version}}/pyproject.toml
+empty_config-{{version}}/src/empty_config/__init__.py

tests/expected_contents/empty-config/whl.txt

@@ -0,0 +1,6 @@
+empty_config-{{version}}.dist-info/LICENSE
+empty_config-{{version}}.dist-info/METADATA
+empty_config-{{version}}.dist-info/RECORD
+empty_config-{{version}}.dist-info/WHEEL
+empty_config-{{version}}.dist-info/entry_points.txt
+empty_config/__init__.py