fix(kpoints): reject zero line interpolation counts

Author: zxy.monado

source/source_cell/klist.cpp

@@ -463,15 +463,23 @@ void K_Vectors::interpolate_k_between(std::ifstream& ifk, std::vector<ModuleBase
         ifk >> ks[iks].z;
         ModuleBase::GlobalFunc::READ_VALUE(ifk, nkl[iks]);
 
-        assert(nkl[iks] >= 0);
+        if (nkl[iks] <= 0)
+        {
+            ModuleBase::WARNING_QUIT("K_Vectors::interpolate_k_between",
+                                     "Line-mode interpolation counts must be positive.");
+        }
         nkstot += nkl[iks];
         /* ISSUE#3482: to distinguish different kline segments */
         if ((nkl[iks] == 1) && (iks != (nks_special - 1))) {
             kpt_segid++;
         }
         kpt_segids.push_back(kpt_segid);
     }
-    assert(nkl[nks_special - 1] == 1);
+    if (nkl[nks_special - 1] != 1)
+    {
+        ModuleBase::WARNING_QUIT("K_Vectors::interpolate_k_between",
+                                 "The final line-mode k-point must have an interpolation count of 1.");
+    }
 
     // std::cout << " nkstot = " << nkstot << std::endl;
     this->renew(nkstot * nspin); // mohan fix bug 2009-09-01

source/source_cell/test/klist_test.cpp

@@ -395,6 +395,21 @@ TEST_F(KlistTest, ReadKpointsLine)
     EXPECT_EQ(kv->get_nkstot(), 122);
 }
 
+TEST_F(KlistTest, ReadKpointsLineRejectsZeroInterpolationCount)
+{
+    ModuleSymmetry::Symmetry::symm_flag = 0;
+    const bool gamma_only_local = false;
+    const double kspacing[3] = {0.0, 0.0, 0.0};
+    const std::string kmesh_type = "gamma";
+    const double koffset[3] = {0.0, 0.0, 0.0};
+    const std::string k_file = "./support/KPT_ZERO_LINE_COUNT";
+    kv->nspin = 1;
+
+    EXPECT_EXIT(kv->read_kpoints(ucell, k_file, gamma_only_local, kspacing, kmesh_type, koffset),
+                ::testing::ExitedWithCode(1),
+                "");
+}
+
 TEST_F(KlistTest, ReadKpointsCartesian)
 {
     const bool gamma_only_local = false;

source/source_cell/test/support/KPT_ZERO_LINE_COUNT

@@ -0,0 +1,5 @@
+K_POINTS
+2
+Line
+0.0 0.0 0.0 0
+0.5 0.0 0.0 1