Merge commit 'b82d68ced2e73c8188f3bbf287c1321033103986' into HEAD

Author: yashikno

.github/workflows/main.yml

@@ -71,7 +71,7 @@ jobs:
         python runTests.py -j4 ${{ matrix.config.tests }}
 
     - name: Upload gtest_output xml
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       if: failure()
       with:
         name: gtest_outputs_xml
@@ -134,7 +134,7 @@ jobs:
         python runTests.py -j2 $MixFunProbTestsArray[(${{ matrix.group }} - 1)]
 
     - name: Upload gtest_output xml
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       if: failure()
       with:
         name: gtest_outputs_xml

stan/math/prim/err/validate_positive_index.hpp

@@ -10,19 +10,21 @@ namespace stan {
 namespace math {
 
 /**
- * Check that simplex is at least size 1
+ * Check that size is at least 1. Used for simplexes and
+ * other constraints that do a (size - 1) operation.
  *
- * @param var_name Name of simplex variable
+ * @param var_name Name of variable
  * @param expr Expression in which variable is declared
- * @param val Size of simplex
- * @throw std::invalid_argument if simplex size is less than 1
+ * @param val Size to check
+ * @throw std::invalid_argument if size is less than 1
  */
 inline void validate_positive_index(const char* var_name, const char* expr,
                                     int val) {
   if (val < 1) {
     [&]() STAN_COLD_PATH {
       std::stringstream msg;
-      msg << "Found dimension size less than one in simplex declaration"
+      msg << "Found dimension size less than one in constrained type "
+             "declaration (simplex, sum_to_zero_vector, etc.)"
           << "; variable=" << var_name << "; dimension size expression=" << expr
           << "; expression value=" << val;
       std::string msg_str(msg.str());