Tests: Add RunCMake helper to run cmake with raw execute_process args

Tests/RunCMake/RunCMake.cmake

@@ -119,12 +119,16 @@ function(run_cmake test)
   else()
     set(RunCMake_TEST_OPTIONS "")
   endif()
+  if(NOT DEFINED RunCMake_TEST_RAW_ARGS)
+    set(RunCMake_TEST_RAW_ARGS "")
+  endif()
   if(NOT RunCMake_TEST_COMMAND_WORKING_DIRECTORY)
     set(RunCMake_TEST_COMMAND_WORKING_DIRECTORY "${RunCMake_TEST_BINARY_DIR}")
   endif()
-  execute_process(
+  string(CONCAT _code [[execute_process(
     COMMAND ${RunCMake_TEST_COMMAND}
             ${RunCMake_TEST_OPTIONS}
+            ]] "${RunCMake_TEST_RAW_ARGS}\n" [[
     WORKING_DIRECTORY "${RunCMake_TEST_COMMAND_WORKING_DIRECTORY}"
     OUTPUT_VARIABLE actual_stdout
     ERROR_VARIABLE ${actual_stderr_var}
@@ -132,7 +136,8 @@ function(run_cmake test)
     ENCODING UTF8
     ${maybe_timeout}
     ${maybe_input_file}
-    )
+    )]])
+  cmake_language(EVAL CODE "${_code}")
   set(msg "")
   if(NOT "${actual_result}" MATCHES "${expect_result}")
     string(APPEND msg "Result is [${actual_result}], not [${expect_result}].\n")
@@ -196,6 +201,9 @@ function(run_cmake test)
       string(REPLACE ";" "\" \"" options "\"${RunCMake_TEST_OPTIONS}\"")
       string(APPEND command " ${options}")
     endif()
+    if(RunCMake_TEST_RAW_ARGS)
+      string(APPEND command " ${RunCMake_TEST_RAW_ARGS}")
+    endif()
     string(APPEND msg "Command was:\n command> ${command}\n")
   endif()
   if(msg)
@@ -228,6 +236,11 @@ function(run_cmake_with_options test)
   run_cmake(${test})
 endfunction()
 
+function(run_cmake_with_raw_args test args)
+  set(RunCMake_TEST_RAW_ARGS "${args}")
+  run_cmake(${test})
+endfunction()
+
 function(ensure_files_match expected_file actual_file)
   if(NOT EXISTS "${expected_file}")
     message(FATAL_ERROR "Expected file does not exist:\n  ${expected_file}")