replace redundant function_record->class_ field with 1 bit

include/pybind11/attr.h

@@ -115,15 +115,15 @@ struct function_record {
     /// True if the function has a '**kwargs' argument
     bool has_kwargs : 1;
 
+    /// True if this is a method
+    bool is_method : 1;
+
     /// Number of arguments
     uint16_t nargs;
 
     /// Python method object
     PyMethodDef *def = nullptr;
 
-    /// Python handle to the associated class (if this is method)
-    handle class_;
-
     /// Python handle to the parent scope (a class or a module)
     handle scope;
 
@@ -235,7 +235,7 @@ template <> struct process_attribute<sibling> : process_attribute_default<siblin
 
 /// Process an attribute which indicates that this function is a method
 template <> struct process_attribute<is_method> : process_attribute_default<is_method> {
-    static void init(const is_method &s, function_record *r) { r->class_ = s.class_; r->scope = s.class_; }
+    static void init(const is_method &s, function_record *r) { r->is_method = true; r->scope = s.class_; }
 };
 
 /// Process an attribute which indicates the parent scope of a method
@@ -251,7 +251,7 @@ template <> struct process_attribute<is_operator> : process_attribute_default<is
 /// Process a keyword argument attribute (*without* a default value)
 template <> struct process_attribute<arg> : process_attribute_default<arg> {
     static void init(const arg &a, function_record *r) {
-        if (r->class_ && r->args.empty())
+        if (r->is_method && r->args.empty())
             r->args.emplace_back("self", nullptr, handle());
         r->args.emplace_back(a.name, nullptr, handle());
     }
@@ -260,17 +260,17 @@ template <> struct process_attribute<arg> : process_attribute_default<arg> {
 /// Process a keyword argument attribute (*with* a default value)
 template <> struct process_attribute<arg_v> : process_attribute_default<arg_v> {
     static void init(const arg_v &a, function_record *r) {
-        if (r->class_ && r->args.empty())
+        if (r->is_method && r->args.empty())
             r->args.emplace_back("self", nullptr, handle());
 
         if (!a.value) {
 #if !defined(NDEBUG)
             auto descr = "'" + std::string(a.name) + ": " + a.type + "'";
-            if (r->class_) {
+            if (r->is_method) {
                 if (r->name)
-                    descr += " in method '" + (std::string) str(r->class_) + "." + (std::string) r->name + "'";
+                    descr += " in method '" + (std::string) str(r->scope) + "." + (std::string) r->name + "'";
                 else
-                    descr += " in method of '" + (std::string) str(r->class_) + "'";
+                    descr += " in method of '" + (std::string) str(r->scope) + "'";
             } else if (r->name) {
                 descr += " in function named '" + (std::string) r->name + "'";
             }

include/pybind11/pybind11.h

@@ -194,10 +194,10 @@ protected:
                 if (type_depth == 0 && text[char_index] != '*' && arg_index < args) {
                     if (!rec->args.empty()) {
                         signature += rec->args[arg_index].name;
-                    } else if (arg_index == 0 && rec->class_) {
+                    } else if (arg_index == 0 && rec->is_method) {
                         signature += "self";
                     } else {
-                        signature += "arg" + std::to_string(arg_index - (rec->class_ ? 1 : 0));
+                        signature += "arg" + std::to_string(arg_index - (rec->is_method ? 1 : 0));
                     }
                     signature += ": ";
                 }
@@ -337,8 +337,8 @@ protected:
             std::free((char *) func->m_ml->ml_doc);
         func->m_ml->ml_doc = strdup(signatures.c_str());
 
-        if (rec->class_) {
-            m_ptr = PYBIND11_INSTANCE_METHOD_NEW(m_ptr, rec->class_.ptr());
+        if (rec->is_method) {
+            m_ptr = PYBIND11_INSTANCE_METHOD_NEW(m_ptr, rec->scope.ptr());
             if (!m_ptr)
                 pybind11_fail("cpp_function::cpp_function(): Could not allocate instance method object");
             Py_DECREF(func);
@@ -1120,7 +1120,7 @@ public:
         const auto property = reinterpret_steal<object>(
             PyObject_CallFunctionObjArgs((PyObject *) &PyProperty_Type, fget.ptr() ? fget.ptr() : Py_None,
                                          fset.ptr() ? fset.ptr() : Py_None, Py_None, doc_obj.ptr(), nullptr));
-        if (rec_fget->class_)
+        if (rec_fget->is_method && rec_fget->scope)
             attr(name) = property;
         else
             metaclass().attr(name) = property;