[PL/ST] Test ST using MPI on strict subdomain.

ProcessLib/HeatConduction/Tests.cmake

@@ -67,3 +67,16 @@ AddTest(
     line_1_line_1e2_pcs_0_ts_500_t_39062500.000000_reference.vtu line_1_line_1e2_pcs_0_ts_500_t_39062500.000000.vtu temperature temperature 1e-11 0.0
     REQUIREMENTS NOT OGS_USE_MPI
 )
+
+# test the source term on a subdomain with the PETSc embedded executable file
+AddTest(
+    NAME 1D_HeatConduction_dirichlet_SourceTerm_PETSc
+    PATH Parabolic/T/1D_dirichlet_source-term
+    EXECUTABLE_ARGS line_1_line_1e2_source_term.prj
+    WRAPPER mpirun
+    WRAPPER_ARGS -np 1
+    TESTER vtkdiff
+    REQUIREMENTS OGS_USE_MPI
+    DIFF_DATA
+    line_1_line_1e2_pcs_0_ts_500_t_39062500.000000_reference.vtu line_1_line_1e2_pcs_0_ts_500_t_39062500_000000_0.vtu temperature temperature 1e-10 0.0
+)