Validate explicit diago_proc bounds (#7739)

Author: Stardust0831

source/source_io/module_parameter/read_input_item_system.cpp

@@ -594,11 +594,21 @@ Available options are:
         item.availability = "Used only for plane wave basis set.";
         read_sync_int(input.diago_proc);
         item.reset_value = [](const Input_Item& item, Parameter& para) {
-            if (para.input.diago_proc > GlobalV::NPROC || para.input.diago_proc <= 0)
+            if (para.input.diago_proc == 0)
             {
                 para.input.diago_proc = GlobalV::NPROC;
             }
         };
+        item.check_value = [](const Input_Item& item, const Parameter& para) {
+            if (para.input.diago_proc < 0)
+            {
+                ModuleBase::WARNING_QUIT("ReadInput", "diago_proc must not be negative");
+            }
+            if (para.input.diago_proc > GlobalV::NPROC)
+            {
+                ModuleBase::WARNING_QUIT("ReadInput", "diago_proc cannot exceed the number of MPI processes");
+            }
+        };
         this->add_item(item);
     }
     {

source/source_io/test/read_input_ptest.cpp

@@ -147,7 +147,7 @@ TEST_F(InputParaTest, ParaRead)
     EXPECT_EQ(param.inp.ndx, 0);
     EXPECT_EQ(param.inp.ndy, 0);
     EXPECT_EQ(param.inp.ndz, 0);
-    EXPECT_EQ(param.inp.diago_proc, std::min(GlobalV::NPROC, 4));
+    EXPECT_EQ(param.inp.diago_proc, GlobalV::NPROC);
     EXPECT_EQ(param.inp.pw_diag_nmax, 50);
     EXPECT_EQ(param.inp.diago_cg_prec, 1);
     EXPECT_EQ(param.inp.pw_diag_ndim, 4);
@@ -456,6 +456,29 @@ TEST_F(InputParaTest, ParaRead)
     EXPECT_DOUBLE_EQ(param.inp.rdmft_power_alpha, 0.656);
 }
 
+TEST_F(InputParaTest, DiagoProc)
+{
+    int rank = 0;
+    int nproc = 0;
+    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+    MPI_Comm_size(MPI_COMM_WORLD, &nproc);
+
+    ModuleIO::ReadInput readinput(rank);
+    readinput.check_ntype_flag = false;
+    Parameter full_param;
+    readinput.read_parameters(full_param, "./support/INPUT.diago_proc_full");
+    EXPECT_EQ(full_param.inp.diago_proc, nproc);
+
+    if (nproc == 4)
+    {
+        ModuleIO::ReadInput subset_readinput(rank);
+        subset_readinput.check_ntype_flag = false;
+        Parameter subset_param;
+        subset_readinput.read_parameters(subset_param, "./support/INPUT.diago_proc_subset");
+        EXPECT_EQ(subset_param.inp.diago_proc, 2);
+    }
+}
+
 // comment out this part of tests, since Parameter is in another directory now, mohan 2025-05-18
 // besides, the following tests will cause strange error in MPI_Finalize()
 // I tried the following modification, it worked well in my own environment, but not in the Github test, Xinyuan 2025-05-25

source/source_io/test/support/INPUT

@@ -33,7 +33,7 @@ out_freq_elec                  0 #the frequency ( >= 0) of electronic iter to ou
 dft_plus_dmft                  0 #true:DFT+DMFT; false: standard DFT calcullation(default)
 rpa                            0 #true:generate output files used in rpa calculation; false:(default)
 mem_saver                      0 #Only for nscf calculations. if set to 1, then a memory saving technique will be used for many k point calculations.
-diago_proc                     4 #the number of procs used to do diagonalization
+diago_proc                     0 #the number of procs used to do diagonalization
 nbspline                       -1 #the order of B-spline basis
 soc_lambda                     1 #The fraction of averaged SOC pseudopotential is given by (1-soc_lambda)
 cal_force                      0 #if calculate the force at the end of the electronic iteration

source/source_io/test/support/INPUT.diago_proc_full

@@ -0,0 +1,2 @@
+INPUT_PARAMETERS
+diago_proc 0

source/source_io/test/support/INPUT.diago_proc_subset

@@ -0,0 +1,2 @@
+INPUT_PARAMETERS
+diago_proc 2

source/source_io/test_serial/read_input_test.cpp

@@ -336,6 +336,24 @@ TEST_F(InputTest, ValidateDeepksOutputFrequency)
     EXPECT_EQ(enabled_param.inp.deepks_out_freq_elec, 2);
 }
 
+TEST_F(InputTest, ValidateDiagoProc)
+{
+    set_nproc(4);
+
+    Parameter full_param;
+    EXPECT_NO_THROW(read_parameters("diago_proc_full_INPUT", "diago_proc 0\n", full_param));
+    EXPECT_EQ(full_param.inp.diago_proc, 4);
+
+    Parameter subset_param;
+    EXPECT_NO_THROW(read_parameters("diago_proc_subset_INPUT", "diago_proc 2\n", subset_param));
+    EXPECT_EQ(subset_param.inp.diago_proc, 2);
+
+    expect_invalid_input("diago_proc_negative_INPUT", "diago_proc -1\n", "diago_proc must not be negative");
+    expect_invalid_input("diago_proc_oversized_INPUT",
+                         "diago_proc 5\n",
+                         "diago_proc cannot exceed the number of MPI processes");
+}
+
 TEST_F(InputTest, Check)
 {
     ModuleIO::ReadInput readinput(0);