Fix #11915 Assert failure in getTemplateNamePosition() (#5403)

Author: chrchr-github

lib/templatesimplifier.cpp

@@ -454,8 +454,9 @@ unsigned int TemplateSimplifier::templateParameters(const Token *tok)
                 if (level == 1)
                     return numberOfParameters;
                 level -= 2;
-            } else if (tok->str() == "," && level == 0) {
-                ++numberOfParameters;
+            } else if (tok->str() == ",") {
+                if (level == 0)
+                    ++numberOfParameters;
                 tok = tok->next();
                 continue;
             }

test/testsimplifytemplate.cpp

@@ -5318,6 +5318,7 @@ class TestSimplifyTemplate : public TestFixture {
         ASSERT_EQUALS(3U, templateParameters("template <class T, class... Args, class Tup = std::tuple<Args&&...>> void f() {}"));
         ASSERT_EQUALS(3U, templateParameters("template <class T, class... Args, class Tup = std::tuple<Args*...>> void f() {}"));
         ASSERT_EQUALS(1U, templateParameters("S<4 < sizeof(uintptr_t)> x;"));
+        ASSERT_EQUALS(2U, templateParameters("template <typename... Ts, typename = std::enable_if_t<std::is_same<Ts..., int>::value>> void g() {}")); // #11915
     }
 
     // Helper function to unit test TemplateSimplifier::getTemplateNamePosition