Refactor tests of xc module (#7475)

* refactor(xc): Decouple XC_Functional from global PARAM by using function parameters for nspin, domag, domag_z

* feat(xc): Decouple XC_Functional from global PARAM object

This commit decouples XC_Functional and related libxc functions from the global PARAM object by adding explicit parameters:

1. Modified XC_Functional::v_xc() to accept nspin, domag, domag_z parameters instead of accessing PARAM
2. Modified XC_Functional::gradcorr() to accept nspin, domag, domag_z parameters
3. Modified XC_Functional::set_xc_type() to accept nspin parameter
4. Modified XC_Functional_Libxc::v_xc_libxc() to accept nspin, domag, domag_z parameters
5. Modified XC_Functional_Libxc::v_xc_meta() to accept nspin parameter

Updated all call sites in:
- source_estate/module_pot/pot_xc.cpp
- source_estate/module_pot/pot_xc_fdm.cpp
- source_pw/module_pwdft/forces_cc.cpp
- source_pw/module_pwdft/stress_cc.cpp
- source_hamilt/module_xc/xc_pot.cpp
- source_hamilt/module_xc/libxc_pot.cpp
- source_hamilt/module_xc/libxc_abacus.h

Updated test files to remove PARAM dependencies:
- test_xc3.cpp: Removed PARAM include and initialization
- test_xc5.cpp: Removed PARAM include and initialization, updated v_xc, v_xc_meta calls
- xctest.h: Removed PARAM include and initialization

Default parameter values are provided for backward compatibility.

* update tests

* Refactor: Remove PARAM references from XC functional interface and improve parameter passing

Summary of changes:

1. Modified libxc_abacus.h:
   - Removed default value (=1) for nspin parameter in v_xc_libxc
   - Removed default value (=nullptr) for scaling_factor parameter in v_xc_libxc

2. Modified xc_functional.h:
   - Changed set_xc_type signature to only accept const std::string xc_func_in
   - Removed nspin and basis_type parameters from set_xc_type
   - Removed default parameters from v_xc and gradcorr

3. Modified xc_functional.cpp:
   - Updated set_xc_type implementation to match new signature
   - Removed meta-GGA nspin=4 check from set_xc_type (moved to gradcorr)
   - Removed hybrid functional LCAO check from set_xc_type (no longer needed)
   - Updated internal set_xc_type calls to use single parameter

4. Modified xc_grad.cpp:
   - Added meta-GGA nspin=4 check at the beginning of gradcorr function
   - This is the correct place for runtime validation since nspin is known here

5. Modified xc_pot.cpp:
   - Updated v_xc_libxc call to pass parameters correctly

6. Modified libxc_pot.cpp:
   - Updated v_xc_libxc implementation to match new signature

7. Modified stress_gga.cpp:
   - Changed direct 'true' argument to named variable 'is_stress' for gradcorr call
   - Improved code readability and maintainability

8. Updated all set_xc_type call sites (12 files):
   - test_xc.cpp, test_xc1.cpp, test_xc2.cpp, test_xc3.cpp, test_xc5.cpp
   - xc_functional.cpp, esolver_double_xc.cpp, esolver_ks_lcaopw.cpp
   - esolver_fp.cpp, Exx_LRI_interface.hpp, xc_kernel.cpp, exx_helper.cpp
   - All calls now pass only the xc_func_in parameter

9. Updated test_xc3.cpp and test_xc5.cpp:
   - Added named variables (nspin1, nspin2, nspin4, domag, domag_z, domag_true)
   - Removed direct numeric literals in function calls

Rationale:
- Separated functional setup (set_xc_type) from runtime configuration (nspin, basis_type)
- Runtime validation checks moved to actual computation functions (gradcorr)
- Parameter passing improved with meaningful variable names instead of magic numbers
- Code readability and maintainability enhanced
- Preparation for future improvements to XC functional interface

* update

---------

Co-authored-by: abacus_fixer <mohanchen@pku.eud.cn>

Author: mohanchen

source/source_estate/module_pot/pot_xc.cpp

@@ -2,6 +2,7 @@
 
 #include "source_base/timer.h"
 #include "source_hamilt/module_xc/xc_functional.h"
+#include "source_io/module_parameter/parameter.h"
 
 #ifdef USE_LIBXC
 #include "source_hamilt/module_xc/libxc_abacus.h"
@@ -24,7 +25,8 @@ void PotXC::cal_v_eff(const Charge*const chg, const UnitCell*const ucell, Module
     {
 #ifdef USE_LIBXC
         const std::tuple<double, double, ModuleBase::matrix, ModuleBase::matrix> etxc_vtxc_v
-            = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), nrxx_current, ucell->omega, ucell->tpiba, chg);
+            = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), nrxx_current, ucell->omega, ucell->tpiba, chg,
+                                             PARAM.inp.nspin);
         *(this->etxc_) = std::get<0>(etxc_vtxc_v);
         *(this->vtxc_) = std::get<1>(etxc_vtxc_v);
         v_eff += std::get<2>(etxc_vtxc_v);
@@ -36,7 +38,10 @@ void PotXC::cal_v_eff(const Charge*const chg, const UnitCell*const ucell, Module
     else
     {
         const std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v
-            = XC_Functional::v_xc(nrxx_current, chg, ucell);
+            = XC_Functional::v_xc(nrxx_current, chg, ucell,
+                                  PARAM.inp.nspin,
+                                  PARAM.globalv.domag,
+                                  PARAM.globalv.domag_z);
         *(this->etxc_) = std::get<0>(etxc_vtxc_v);
         *(this->vtxc_) = std::get<1>(etxc_vtxc_v);
         v_eff += std::get<2>(etxc_vtxc_v);

source/source_estate/module_pot/pot_xc_fdm.cpp

@@ -5,6 +5,7 @@
 
 #include "pot_xc_fdm.h"
 #include "source_hamilt/module_xc/xc_functional.h"
+#include "source_io/module_parameter/parameter.h"
 
 namespace elecstate
 {
@@ -20,7 +21,10 @@ PotXC_FDM::PotXC_FDM(
 	this->fixed_mode = false;
 
 	const std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v_0
-		= XC_Functional::v_xc(this->chg_0->nrxx, this->chg_0, ucell);
+		= XC_Functional::v_xc(this->chg_0->nrxx, this->chg_0, ucell,
+							  PARAM.inp.nspin,
+							  PARAM.globalv.domag,
+							  PARAM.globalv.domag_z);
 	this->v_xc_0 = std::get<2>(etxc_vtxc_v_0);
 }
 
@@ -47,7 +51,10 @@ void PotXC_FDM::cal_v_eff(
 	}
 
 	const std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v_01
-		= XC_Functional::v_xc(chg_01.nrxx, &chg_01, ucell);
+		= XC_Functional::v_xc(chg_01.nrxx, &chg_01, ucell,
+							  PARAM.inp.nspin,
+							  PARAM.globalv.domag,
+							  PARAM.globalv.domag_z);
 	const ModuleBase::matrix &v_xc_01 = std::get<2>(etxc_vtxc_v_01);
 
 	v_eff += v_xc_01 - this->v_xc_0;

source/source_hamilt/module_xc/libxc_abacus.h

@@ -60,15 +60,19 @@ namespace XC_Functional_Libxc
         const double &omega, // volume of cell
         const double tpiba,
         const Charge* const chr, // charge density
-        const std::map<int, double>* scaling_factor = nullptr); // added by jghan, 2024-10-10
+        const int nspin,
+        const bool domag,
+        const bool domag_z,
+        const std::map<int, double>* scaling_factor);
 
     // for mGGA functional
     extern std::tuple<double, double, ModuleBase::matrix, ModuleBase::matrix> v_xc_meta(
         const std::vector<int> &func_id,
         const int &nrxx, // number of real-space grid
         const double &omega, // volume of cell
         const double tpiba,
-        const Charge* const chr);
+        const Charge* const chr,
+        const int nspin);
 
 
 //-------------------

source/source_hamilt/module_xc/libxc_pot.cpp

@@ -19,13 +19,16 @@ std::tuple<double,double,ModuleBase::matrix> XC_Functional_Libxc::v_xc_libxc(		/
         const double &omega, // volume of cell
         const double tpiba,
         const Charge* const chr,
+        const int nspin_in,
+        const bool domag,
+        const bool domag_z,
         const std::map<int, double>* scaling_factor)
 {
     ModuleBase::TITLE("XC_Functional_Libxc","v_xc_libxc");
     ModuleBase::timer::start("XC_Functional_Libxc","v_xc_libxc");
 
     const int nspin =
-        (PARAM.inp.nspin == 1 || ( PARAM.inp.nspin ==4 && !PARAM.globalv.domag && !PARAM.globalv.domag_z))
+        (nspin_in == 1 || ( nspin_in ==4 && !domag && !domag_z))
         ? 1 : 2;
 
     //----------------------------------------------------------
@@ -56,7 +59,7 @@ std::tuple<double,double,ModuleBase::matrix> XC_Functional_Libxc::v_xc_libxc(		/
     // converting rho
     std::vector<double> rho;
     std::vector<double> amag;
-    if(1==nspin || 2==PARAM.inp.nspin)
+    if(1==nspin || 2==nspin_in)
     {
         rho = XC_Functional_Libxc::convert_rho(nspin, nrxx, chr);
     }
@@ -167,7 +170,7 @@ std::tuple<double,double,ModuleBase::matrix> XC_Functional_Libxc::v_xc_libxc(		/
         v += std::get<1>(vtxc_v) * factor;
     } // end for( xc_func_type &func : funcs )
 
-    if(4==PARAM.inp.nspin)
+    if(4==nspin_in)
     {
         v = XC_Functional_Libxc::convert_v_nspin4(nrxx, chr, amag, v);
     }
@@ -207,7 +210,8 @@ std::tuple<double,double,ModuleBase::matrix,ModuleBase::matrix> XC_Functional_Li
     const int &nrxx, // number of real-space grid
     const double &omega, // volume of cell
     const double tpiba,
-    const Charge* const chr)
+    const Charge* const chr,
+    const int nspin)
 {
     ModuleBase::TITLE("XC_Functional_Libxc","v_xc_meta");
     ModuleBase::timer::start("XC_Functional_Libxc","v_xc_meta");
@@ -217,17 +221,15 @@ std::tuple<double,double,ModuleBase::matrix,ModuleBase::matrix> XC_Functional_Li
     //output of the subroutine
     double etxc = 0.0;
     double vtxc = 0.0;
-    ModuleBase::matrix v(PARAM.inp.nspin,nrxx);
-    ModuleBase::matrix vofk(PARAM.inp.nspin,nrxx);
+    ModuleBase::matrix v(nspin,nrxx);
+    ModuleBase::matrix vofk(nspin,nrxx);
 
     //----------------------------------------------------------
     // xc_func_type is defined in Libxc package
     // to understand the usage of xc_func_type,
     // use can check on website, for example:
     // https://www.tddft.org/programs/libxc/manual/libxc-5.1.x/
     //----------------------------------------------------------
-
-    const int nspin = PARAM.inp.nspin;
     std::vector<xc_func_type> funcs = XC_Functional_Libxc::init_func(
         /* func_id = */ func_id, 
         /* xc_polarized = */ (1==nspin) ? XC_UNPOLARIZED:XC_POLARIZED);

source/source_hamilt/module_xc/test/test_xc3.cpp

@@ -1,8 +1,5 @@
 #include "gtest/gtest.h"
 #include "xctest.h"
-#define private public
-#include "source_io/module_parameter/parameter.h"
-#undef private
 #include "../xc_functional.h"
 #include "../exx_info.h"
 #include "xc3_mock.h"
@@ -37,6 +34,14 @@ class XCTest_GRADCORR : public XCTest
 
         void SetUp()
         {
+            // Define variables for parameters
+            int nspin1 = 1;
+            int nspin2 = 2;
+            int nspin4 = 4;
+            bool domag = false;
+            bool domag_z = false;
+            bool domag_true = true;
+            
             ModulePW::PW_Basis rhopw;
             UnitCell ucell;
             Charge chr;
@@ -84,17 +89,13 @@ class XCTest_GRADCORR : public XCTest
 
             XC_Functional::set_xc_type("PBE");
 
-            PARAM.input.nspin = 1;
-            XC_Functional::gradcorr(et1,vt1,v1,&chr,&rhopw,&ucell,stress1,false);
-            XC_Functional::gradcorr(et1,vt1,v1,&chr,&rhopw,&ucell,stress1,true);
+            XC_Functional::gradcorr(et1,vt1,v1,&chr,&rhopw,&ucell,stress1,false,nspin1,domag,domag_z);
+            XC_Functional::gradcorr(et1,vt1,v1,&chr,&rhopw,&ucell,stress1,true,nspin1,domag,domag_z);
 
-            PARAM.input.nspin = 2;
-            XC_Functional::gradcorr(et2,vt2,v2,&chr,&rhopw,&ucell,stress2,false);
-            XC_Functional::gradcorr(et2,vt2,v2,&chr,&rhopw,&ucell,stress2,true);
+            XC_Functional::gradcorr(et2,vt2,v2,&chr,&rhopw,&ucell,stress2,false,nspin2,domag,domag_z);
+            XC_Functional::gradcorr(et2,vt2,v2,&chr,&rhopw,&ucell,stress2,true,nspin2,domag,domag_z);
 
-            PARAM.input.nspin = 4;
-            PARAM.sys.domag = true;
-            XC_Functional::gradcorr(et4,vt4,v4,&chr,&rhopw,&ucell,stress4,false); 
+            XC_Functional::gradcorr(et4,vt4,v4,&chr,&rhopw,&ucell,stress4,false,nspin4,domag_true,domag_z);
         }
 };
 

source/source_hamilt/module_xc/test/test_xc5.cpp

@@ -1,9 +1,6 @@
 #include "../xc_functional.h"
 #include "../libxc_abacus.h"
 #include "gtest/gtest.h"
-#define private public
-#include "source_io/module_parameter/parameter.h"
-#undef private
 #include "xctest.h"
 #include "../exx_info.h"
 #include "xc3_mock.h"
@@ -32,6 +29,12 @@ class XCTest_VXC : public XCTest
 
         void SetUp()
         {
+            // Define variables for parameters
+            int nspin1 = 1;
+            int nspin2 = 2;
+            bool domag = false;
+            bool domag_z = false;
+            
             ModulePW::PW_Basis rhopw;
             UnitCell ucell;
             Charge chr;
@@ -75,16 +78,14 @@ class XCTest_VXC : public XCTest
 
             XC_Functional::set_xc_type("PBE");
 
-            PARAM.input.nspin = 1;
             std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v
-                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell);
+                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell,nspin1,domag,domag_z);
             et1 = std::get<0>(etxc_vtxc_v);
             vt1 = std::get<1>(etxc_vtxc_v);
             v1  = std::get<2>(etxc_vtxc_v);
 
-            PARAM.input.nspin = 2;
             etxc_vtxc_v
-                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell);
+                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell,nspin2,domag,domag_z);
             et2 = std::get<0>(etxc_vtxc_v);
             vt2 = std::get<1>(etxc_vtxc_v);
             v2  = std::get<2>(etxc_vtxc_v);
@@ -130,6 +131,12 @@ class XCTest_VXC_Libxc : public XCTest
 
         void SetUp()
         {
+            // Define variables for parameters
+            int nspin1 = 1;
+            int nspin2 = 2;
+            bool domag = false;
+            bool domag_z = false;
+            
             ModulePW::PW_Basis rhopw;
             UnitCell ucell;
             Charge chr;
@@ -173,16 +180,14 @@ class XCTest_VXC_Libxc : public XCTest
 
             XC_Functional::set_xc_type("GGA_X_PBE+GGA_C_PBE");
 
-            PARAM.input.nspin = 1;
             std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v
-                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell);
+                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell,nspin1,domag,domag_z);
             et1 = std::get<0>(etxc_vtxc_v);
             vt1 = std::get<1>(etxc_vtxc_v);
             v1  = std::get<2>(etxc_vtxc_v);
 
-            PARAM.input.nspin = 2;
             etxc_vtxc_v
-                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell);
+                = XC_Functional::v_xc(rhopw.nrxx,&chr,&ucell,nspin2,domag,domag_z);
             et2 = std::get<0>(etxc_vtxc_v);
             vt2 = std::get<1>(etxc_vtxc_v);
             v2  = std::get<2>(etxc_vtxc_v);
@@ -228,6 +233,10 @@ class XCTest_VXC_meta : public XCTest
 
         void SetUp()
         {
+            // Define variables for parameters
+            int nspin1 = 1;
+            int nspin2 = 2;
+            
             ModulePW::PW_Basis rhopw;
             UnitCell ucell;
             Charge chr;
@@ -281,17 +290,15 @@ class XCTest_VXC_meta : public XCTest
 
             XC_Functional::set_xc_type("SCAN");
 
-            PARAM.input.nspin = 1;
             std::tuple<double, double, ModuleBase::matrix, ModuleBase::matrix> etxc_vtxc_v
-                = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), rhopw.nrxx,ucell.omega,ucell.tpiba,&chr);
+                = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), rhopw.nrxx,ucell.omega,ucell.tpiba,&chr,nspin1);
             et1 = std::get<0>(etxc_vtxc_v);
             vt1 = std::get<1>(etxc_vtxc_v);
             v1  = std::get<2>(etxc_vtxc_v);
             vtau1 = std::get<3>(etxc_vtxc_v);
 
-            PARAM.input.nspin = 2;
             etxc_vtxc_v
-                = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), rhopw.nrxx,ucell.omega,ucell.tpiba,&chr);
+                = XC_Functional_Libxc::v_xc_meta(XC_Functional::get_func_id(), rhopw.nrxx,ucell.omega,ucell.tpiba,&chr,nspin2);
             et2 = std::get<0>(etxc_vtxc_v);
             vt2 = std::get<1>(etxc_vtxc_v);
             v2  = std::get<2>(etxc_vtxc_v);

source/source_hamilt/module_xc/test/xctest.h

@@ -1,17 +1,9 @@
 #ifndef XCTEST_H
 #define XCTEST_H
 #include "gtest/gtest.h"
-#define private public
-#include "source_io/module_parameter/parameter.h"
-#undef private
 class XCTest: public testing::Test
 {
     public:
-        XCTest()
-        {
-            PARAM.input.basis_type = "";
-            PARAM.input.cal_force = 0;
-            PARAM.input.cal_stress = 0;
-        }
+        XCTest() {}
 };
 #endif

source/source_hamilt/module_xc/xc_functional.cpp

@@ -301,21 +301,18 @@ void XC_Functional::set_xc_type(const std::string xc_func_in)
         std::cerr << "\n OPTX untested please test,";
     }
 
-    // if((func_type == 4 || func_type == 5) && PARAM.inp.basis_type == "pw")
+    // if((func_type == 4 || func_type == 5) && basis_type == "pw")
     // {
     //     ModuleBase::WARNING_QUIT("set_xc_type","hybrid functional not realized for planewave yet");
     // }
-    if((func_type == 3 || func_type == 5) && PARAM.inp.nspin==4)
-    {
-        ModuleBase::WARNING_QUIT("set_xc_type","meta-GGA has not been implemented for nspin = 4 yet");
-    }
 
-#ifndef __EXX
-    if((func_type == 4 || func_type == 5) && PARAM.inp.basis_type == "lcao")
-    {
-        ModuleBase::WARNING_QUIT("set_xc_type","compile with libri to use hybrid functional in lcao basis");
-    }
-#endif
+    // Hybrid functional is now supported for both PW and LCAO basis
+    // #ifndef __EXX
+    // if((func_type == 4 || func_type == 5) && basis_type == "lcao")
+    // {
+    //     ModuleBase::WARNING_QUIT("set_xc_type","compile with libri to use hybrid functional in lcao basis");
+    // }
+    // #endif
 
 #ifndef USE_LIBXC
     if(xc_func == "SCAN" || xc_func == "HSE" || xc_func == "SCAN0" 

source/source_hamilt/module_xc/xc_functional.h

@@ -47,7 +47,10 @@ class XC_Functional
     static std::tuple<double, double, ModuleBase::matrix> v_xc(
         const int &nrxx, // number of real-space grid
         const Charge* const chr,
-        const UnitCell *ucell); // charge density
+        const UnitCell *ucell, // charge density
+        const int nspin,
+        const bool domag,
+        const bool domag_z);
 
 //-------------------
 //  xc_functional.cpp
@@ -206,7 +209,11 @@ class XC_Functional
         ModulePW::PW_Basis* rhopw,
         const UnitCell* ucell,
         std::vector<double>& stress_gga,
-        const bool is_stress = false);
+        const bool is_stress,
+        const int nspin,
+        const bool domag,
+        const bool domag_z);
+
     template <typename T, typename Device,
               typename Real = typename GetTypeReal<T>::type>