feat(assert): add "object" class type guard

This facilitates the output of diagnostic data.

Author: Damian Rouson

src/assertions_implementation.F90

@@ -12,6 +12,7 @@
   module procedure assert
     use iso_fortran_env, only : error_unit
     use string_functions_interface, only : string
+    use object_interface, only : object
 
     character(len=:), allocatable :: header, trailer
     integer, parameter :: max_this_image_digits=9
@@ -32,21 +33,25 @@
         else
 
           block
-            character(len=*), parameter :: lede = "with diagnostic data"
+            character(len=*), parameter :: prefix = "with diagnostic data"
+            integer, parameter :: max_data_length = 1024
 
             select type(diagnostic_data)
               type is(character(len=*))
-                trailer =  lede // diagnostic_data
+                trailer =  prefix // diagnostic_data
               type is(integer)
-                trailer = lede // string(diagnostic_data)
+                trailer = prefix // string(diagnostic_data)
+              class is(object)
+                trailer = repeat(" ", ncopies =  max_data_length)
+                write(trailer,*) diagnostic_data
               class default
-                trailer = lede // 'of unsupported type'
+                trailer = prefix // 'of unsupported type'
             end select
           end block
 
         end if
 
-        error stop header // trailer
+        error stop header // trim(trailer)
 
       end if
 

src/object_interface.f90

@@ -1,16 +1,11 @@
-!! author: Damian Rouson, GSE LLC
-!! category: Morfeus-FD
-!! summary: Abstract base type, `object`
-!!
-!! ### Copyright notice
-!!
-!!     ```
-!!     (c) 2019-2020 Guide Star Engineering, LLC
-!!     This Software was developed for the US Nuclear Regulatory Commission (US NRC) under contract
-!!     "Multi-Dimensional Physics Implementation into Fuel Analysis under Steady-state and Transients (FAST)",
-!!     contract # NRC-HQ-60-17-C-0007
-!!     ```
-
+! ### Copyright notice
+!
+!     ```
+!     (c) 2019-2020 Guide Star Engineering, LLC
+!     This Software was developed for the US Nuclear Regulatory Commission (US NRC) under contract
+!     "Multi-Dimensional Physics Implementation into Fuel Analysis under Steady-state and Transients (FAST)",
+!     contract # NRC-HQ-60-17-C-0007
+!     ```
 module object_interface
   implicit none
 
@@ -31,6 +26,8 @@ module object_interface
   contains
     procedure :: mark_as_defined
     procedure :: user_defined
+    procedure(write_interface), deferred :: write_formatted
+    generic :: write(formatted) => write_formatted
   end type
 
   interface
@@ -50,4 +47,16 @@ pure module function user_defined(this) result(is_defined)
 
   end interface
 
+  abstract interface
+    subroutine write_interface(self, unit, iotype, v_list, iostat, iomsg)
+      import object
+      class(object), intent(in) :: self
+      integer, intent(in) :: unit
+      character(*), intent(in) :: iotype
+      integer, intent(in) :: v_list(:)
+      integer, intent(out) :: iostat
+      character(*), intent(inout) :: iomsg
+    end subroutine
+  end interface
+
 end module object_interface