Add tests that showcase cmake -S limitations

Tests/RunCMake/CommandLine/RunCMakeTest.cmake

@@ -130,6 +130,19 @@ project(ExplicitDirsMissing LANGUAGES NONE)
   set(RunCMake_TEST_BINARY_DIR "${source_dir}")
   run_cmake_with_options(no-S-B -DFOO=BAR)
 
+  file(WRITE ${source_dir}/CMakeLists.txt [=[
+cmake_minimum_required(VERSION 3.13)
+project(ExplicitDirsMissing LANGUAGES NONE)
+if(CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)
+  message(FATAL_ERROR "CWD used as binary dir")
+endif()
+]=])
+
+  file(REMOVE_RECURSE "${source_dir}/build")
+  # Test with a setup where binary_dir won't be created by `run_cmake_with_options`
+  run_cmake_with_options(S-arg-build-dir-not-created -S ${source_dir} build/)
+  run_cmake_with_options(S-arg-reverse-build-dir-not-created build/ -S${source_dir} )
+
   set(source_dir ${RunCMake_SOURCE_DIR}/ExplicitDirs)
   set(binary_dir ${RunCMake_BINARY_DIR}/ExplicitDirs-build)