Relocate multiple-interpreters tests

Author: XuehaiPan

tests/CMakeLists.txt

@@ -157,7 +157,7 @@ set(PYBIND11_TEST_FILES
     test_methods_and_attributes
     test_modules
     test_multiple_inheritance
-    test_multiple_interpreters.py
+    test_multiple_interpreters/test_multiple_interpreters.py
     test_native_enum
     test_numpy_array
     test_numpy_dtypes
@@ -578,24 +578,8 @@ add_custom_target(
   USES_TERMINAL)
 
 if(NOT PYBIND11_CUDA_TESTS)
-  # This module doesn't get mixed with other test modules because those aren't subinterpreter safe.
-  pybind11_add_module(mod_per_interpreter_gil THIN_LTO mod_per_interpreter_gil.cpp)
-  pybind11_add_module(mod_shared_interpreter_gil THIN_LTO mod_shared_interpreter_gil.cpp)
-  set_target_properties(mod_per_interpreter_gil PROPERTIES LIBRARY_OUTPUT_DIRECTORY
-                                                           "$<1:${CMAKE_CURRENT_BINARY_DIR}>")
-  set_target_properties(mod_shared_interpreter_gil PROPERTIES LIBRARY_OUTPUT_DIRECTORY
-                                                              "$<1:${CMAKE_CURRENT_BINARY_DIR}>")
-  if(PYBIND11_TEST_SMART_HOLDER)
-    target_compile_definitions(
-      mod_per_interpreter_gil
-      PUBLIC -DPYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE
-    )
-    target_compile_definitions(
-      mod_shared_interpreter_gil
-      PUBLIC -DPYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE
-    )
-  endif()
-  add_dependencies(pytest mod_per_interpreter_gil mod_shared_interpreter_gil)
+  # Multiple interpreters tests are in a separate subdirectory
+  add_subdirectory(test_multiple_interpreters)
 endif()
 
 if(PYBIND11_TEST_OVERRIDE)

tests/test_multiple_interpreters/CMakeLists.txt

@@ -0,0 +1,39 @@
+# CMakeLists.txt -- Build system for the pybind11 multiple interpreters test suite
+#
+# Copyright (c) 2015 Wenzel Jakob <[email protected]>
+#
+# All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+set(PYBIND11_MULTIPLE_INTERPRETERS_TEST_FILES test_multiple_interpreters.py)
+
+# These modules don't get mixed with other test modules because those aren't subinterpreter safe.
+pybind11_add_module(mod_per_interpreter_gil THIN_LTO mod_per_interpreter_gil.cpp)
+pybind11_add_module(mod_shared_interpreter_gil THIN_LTO mod_shared_interpreter_gil.cpp)
+pybind11_enable_warnings(mod_per_interpreter_gil)
+pybind11_enable_warnings(mod_shared_interpreter_gil)
+
+# Put the built modules next to `pybind11_tests.so` so that the test scripts can find them.
+get_target_property(pybind11_tests_output_directory pybind11_tests LIBRARY_OUTPUT_DIRECTORY)
+set_target_properties(mod_per_interpreter_gil PROPERTIES LIBRARY_OUTPUT_DIRECTORY
+                                                         "${pybind11_tests_output_directory}")
+set_target_properties(mod_shared_interpreter_gil PROPERTIES LIBRARY_OUTPUT_DIRECTORY
+                                                            "${pybind11_tests_output_directory}")
+
+if(PYBIND11_TEST_SMART_HOLDER)
+  target_compile_definitions(
+    mod_per_interpreter_gil
+    PUBLIC -DPYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE)
+  target_compile_definitions(
+    mod_shared_interpreter_gil
+    PUBLIC -DPYBIND11_RUN_TESTING_WITH_SMART_HOLDER_AS_DEFAULT_BUT_NEVER_USE_IN_PRODUCTION_PLEASE)
+endif()
+
+add_dependencies(pytest mod_per_interpreter_gil mod_shared_interpreter_gil)
+
+# Convert relative to full file names and add to pytest test files
+list(TRANSFORM PYBIND11_MULTIPLE_INTERPRETERS_TEST_FILES PREPEND "${CMAKE_CURRENT_SOURCE_DIR}/")
+list(APPEND PYBIND11_ABS_PYTEST_FILES ${PYBIND11_MULTIPLE_INTERPRETERS_TEST_FILES})
+set(PYBIND11_ABS_PYTEST_FILES
+    ${PYBIND11_ABS_PYTEST_FILES}
+    PARENT_SCOPE)