ENH: Test included header in Fortran preprocessing

This extends the Fortran preprocessing test to include a header file
through a preprocessor directive.

Tests/Fortran/CMakeLists.txt

@@ -127,6 +127,7 @@ if(CMAKE_Fortran_COMPILER_SUPPORTS_F90)
     in_interface/module.f90)
 
   add_definitions(-DFOO -DBAR=1)
+  include_directories(${testf_SOURCE_DIR}/include)
   add_executable(test_preprocess test_preprocess.F90)
 
   set(TEST_MODULE_DEPENDS 1)

Tests/Fortran/include/test_preprocess.h

@@ -0,0 +1,5 @@
+#ifdef BAR
+  PRINT * , 'BAR was defined via ADD_DEFINITIONS'
+#else
+  PRINT *, 'If you can read this something went wrong'
+#endif

Tests/Fortran/test_preprocess.F90

@@ -46,10 +46,6 @@ PROGRAM PPTEST
 #endif
 ! 0 ; <empty>
 
-#ifdef BAR
+#include "test_preprocess.h"
-  PRINT * , 'BAR was defined via ADD_DEFINITIONS'
-#else
-  PRINT *, 'If you can read this something went wrong'
-#endif
 
 END PROGRAM