Tests/bpy: Add installation verification test

Makes it slightly easier to test whether the installed module works
or not. Depends on D10656

Ref T86579
Reviewed By: mont29, campbellbarton
Differential Revision: https://developer.blender.org/D10665

tests/CMakeLists.txt

@@ -51,5 +51,10 @@ if(WITH_BLENDER AND WITH_PYTHON AND NOT WITH_PYTHON_MODULE)
   add_subdirectory(python)
 endif()
 
+# Blender as python module tests.
+if(WITH_PYTHON_MODULE)
+  add_subdirectory(blender_as_python_module)
+endif()
+
 # GTest
 add_subdirectory(gtests)

tests/blender_as_python_module/CMakeLists.txt

+# ***** BEGIN GPL LICENSE BLOCK *****
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# The Original Code is Copyright (C) 2021, Blender Foundation
+# All rights reserved.
+#
+# ***** END GPL LICENSE BLOCK *****
+
+function(add_blender_as_python_module_test testname testscript)
+  if(NOT TEST_PYTHON_EXE)
+    message(FATAL_ERROR "No Python configured for running tests, set TEST_PYTHON_EXE.")
+  endif()
+
+  add_test(
+    NAME ${testname}
+    COMMAND ${TEST_PYTHON_EXE} ${testscript} ${ARGN}
+  )
+endfunction()
+
+add_blender_as_python_module_test(import_bpy ${CMAKE_CURRENT_LIST_DIR}/import_bpy.py)

tests/blender_as_python_module/import_bpy.py

+# ***** BEGIN GPL LICENSE BLOCK *****
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+# ***** END GPL LICENSE BLOCK *****
+
+# Just import bpy and see if there are any dynamic loader errors.
+import bpy