Tests: Cover genex behavior in CROSSCOMPILING_EMULATOR test case

A `$<TARGET_FILE:tgt>` generator expression does not cause insertion of
the emulator.  Add a test covering this.  While at it, extend the test
case to cover executables in a subdirectory.  Also make the test
matching expressions more robust to support multiple add_test calls
without mixing them while matching.

Tests/RunCMake/CrosscompilingEmulator/AddTest-check.cmake

@@ -4,9 +4,25 @@ if(EXISTS "${testfile}")
 else()
   message(FATAL_ERROR "Could not find expected CTestTestfile.cmake.")
 endif()
-if(testfile_contents MATCHES "add_test[(]DoesNotUseEmulator ^(pseudo_emulator)+$")
-  message(SEND_ERROR "Used emulator when it should not be used.")
+
+set(error_details "There is a problem with generated test file: ${testfile}")
+
+if(testfile_contents MATCHES "add_test[(]DoesNotUseEmulator [^\n]+pseudo_emulator[^\n]+\n")
+  message(SEND_ERROR "Used emulator when it should not be used. ${error_details}")
 endif()
-if(NOT testfile_contents MATCHES "add_test[(]UsesEmulator .+pseudo_emulator.+$")
-  message(SEND_ERROR "Did not use emulator when it should be used.")
+
+if(NOT testfile_contents MATCHES "add_test[(]UsesEmulator [^\n]+pseudo_emulator[^\n]+\n")
+  message(SEND_ERROR "Did not use emulator when it should be used. ${error_details}")
+endif()
+
+if(testfile_contents MATCHES "add_test[(]DoesNotUseEmulatorWithGenex [^\n]+pseudo_emulator[^\n]+\n")
+  message(SEND_ERROR "Used emulator when it should not be used. ${error_details}")
+endif()
+
+if(NOT testfile_contents MATCHES "add_test[(]UsesEmulatorWithExecTargetFromSubdirAddedWithoutGenex [^\n]+pseudo_emulator[^\n]+\n")
+  message(SEND_ERROR "Did not use emulator when it should be used. ${error_details}")
+endif()
+
+if(testfile_contents MATCHES "add_test[(]DoesNotUseEmulatorWithExecTargetFromSubdirAddedWithGenex [^\n]+pseudo_emulator[^\n]+\n")
+  message(SEND_ERROR "Used emulator when it should not be used. ${error_details}")
 endif()

Tests/RunCMake/CrosscompilingEmulator/AddTest.cmake

@@ -4,5 +4,17 @@ add_test(NAME DoesNotUseEmulator
   COMMAND ${CMAKE_COMMAND} -E echo "Hi")
 
 add_executable(generated_exe simple_src.cxx)
+
 add_test(NAME UsesEmulator
   COMMAND generated_exe)
+
+add_test(NAME DoesNotUseEmulatorWithGenex
+  COMMAND $<TARGET_FILE:generated_exe>)
+
+add_subdirectory(AddTest)
+
+add_test(NAME UsesEmulatorWithExecTargetFromSubdirAddedWithoutGenex
+  COMMAND generated_exe_in_subdir_added_to_test_without_genex)
+
+add_test(NAME DoesNotUseEmulatorWithExecTargetFromSubdirAddedWithGenex
+  COMMAND $<TARGET_FILE:generated_exe_in_subdir_added_to_test_with_genex>)

Tests/RunCMake/CrosscompilingEmulator/AddTest/CMakeLists.txt

+add_executable(generated_exe_in_subdir_added_to_test_without_genex ${CMAKE_CURRENT_SOURCE_DIR}/../simple_src.cxx)
+
+add_executable(generated_exe_in_subdir_added_to_test_with_genex ${CMAKE_CURRENT_SOURCE_DIR}/../simple_src.cxx)