GTest functional tests that include parameters and uORB messaging (#12521)

* Add kdevelop to gitignore

* Add test stubs

* Rename px4_add_gtest to px4_add_unit_gtest

* Add infrastructure to run functional tests

* Add example tests with parameters and uorb messages

* Fix memory issues in destructors in uORB manager and CDev

* Add a more real-world test of the collision prevention

cmake/gtest/px4_add_gtest.cmake

@@ -39,12 +39,12 @@ include(px4_base)
 #
 #	Adds a googletest unit test to the test_results target.
 #
-function(px4_add_gtest)
+function(px4_add_unit_gtest)
 	# skip if unit testing is not configured
 	if(BUILD_TESTING)
 		# parse source file and library dependencies from arguments
 		px4_parse_function_args(
-			NAME px4_add_gtest
+			NAME px4_add_unit_gtest
 			ONE_VALUE SRC
 			MULTI_VALUE LINKLIBS
 			REQUIRED SRC
@@ -62,7 +62,57 @@ function(px4_add_gtest)
 		target_link_libraries(${TESTNAME} ${LINKLIBS} gtest_main)
 
 		# add the test to the ctest plan
-		add_test(NAME ${TESTNAME} COMMAND ${TESTNAME})
+		add_test(NAME ${TESTNAME}
+		         COMMAND ${TESTNAME}
+		         WORKING_DIRECTORY ${PX4_BINARY_DIR})
+
+		# attach it to the unit test target
+		add_dependencies(test_results ${TESTNAME})
+	endif()
+endfunction()
+
+function(px4_add_functional_gtest)
+	# skip if unit testing is not configured
+	if(BUILD_TESTING)
+		# parse source file and library dependencies from arguments
+		px4_parse_function_args(
+			NAME px4_add_functional_gtest
+			ONE_VALUE SRC
+			MULTI_VALUE LINKLIBS
+			REQUIRED SRC
+			ARGN ${ARGN})
+
+		# infer test name from source filname
+		get_filename_component(TESTNAME ${SRC} NAME_WE)
+		string(REPLACE Test "" TESTNAME ${TESTNAME})
+		set(TESTNAME functional-${TESTNAME})
+
+		# build a binary for the unit test
+		add_executable(${TESTNAME} EXCLUDE_FROM_ALL ${SRC})
+
+		# link the libary to test and gtest
+		target_link_libraries(${TESTNAME} ${LINKLIBS} gtest_main
+		                                              px4_daemon
+		                                              px4_platform
+		                                              modules__uORB
+		                                              px4_layer
+		                                              systemlib
+		                                              cdev
+		                                              px4_work_queue
+		                                              px4_daemon
+		                                              work_queue
+		                                              parameters
+		                                              perf
+		                                              tinybson
+		                                              uorb_msgs
+		                                              test_stubs)  #put test_stubs last
+
+		# add the test to the ctest plan
+		add_test(NAME ${TESTNAME}
+		         # functional tests need to run in a new process for each test,
+		         # since they set up and tear down system components
+		         COMMAND ${PX4_SOURCE_DIR}/Tools/run-gtest-isolated.py ${TESTNAME}
+		         WORKING_DIRECTORY ${PX4_BINARY_DIR})
 
 		# attach it to the unit test target
 		add_dependencies(test_results ${TESTNAME})