bindgen: Fix dropped constructors and out params

A static function that makes the class it sits on was not read at all,
so every named constructor in the API was missing.

An out parameter fared worse: it was declared as the pointer it is
passed through, handed to the C function uninitialised and by value,
and left out of the result. A `gboolean` method that answers through
one now binds as a nullable, and any other out parameter is refused
rather than bound as a result the caller cannot read.

src/frida_bindgen/codegen.py

@@ -4,6 +4,7 @@ import textwrap
 from pathlib import Path
 from typing import Dict, List, Optional
 
+from frida_bindgen_core import Direction
 from .model import (ClassObjectType, CustomTypeKind, Enumeration,
                     InterfaceObjectType, Method, Model, ObjectType, Parameter,
                     Procedure, Property, Signal, Tuple, to_camel_case,
@@ -1517,8 +1518,12 @@ def generate_parameter_variable_declarations(
     decls = []
 
     for param in proc.parameters:
-        line = f"{param.type.c.replace('const ', '')} {param.name}"
-        if initialize:
+        c_type = param.type.c.replace("const ", "")
+        is_out = param.direction == Direction.OUT
+        if is_out:
+            c_type = c_type[:-1].strip()
+        line = f"{c_type} {param.name}"
+        if initialize and not is_out:
             default_val = param.type.default_value
             if default_val is not None:
                 line += f" = {default_val}"
@@ -1592,7 +1597,12 @@ def generate_call_arguments_code(
     names = []
     if instance_arg is not None:
         names.append(instance_arg)
-    names += [f"{storage_prefix}{param.name}" for param in proc.parameters]
+    names += [
+        f"&{storage_prefix}{param.name}"
+        if param.direction == Direction.OUT
+        else f"{storage_prefix}{param.name}"
+        for param in proc.parameters
+    ]
     if proc.throws:
         names.append(f"&{storage_prefix}error")
     return ", ".join(names)
@@ -1611,6 +1621,13 @@ def generate_return_assignment_code(method: Method, storage_prefix: str) -> str:
 
 
 def generate_return_conversion_code(method: Method, storage_prefix: str) -> str:
+    out = method.optional_out_parameter
+    if out is not None:
+        convert = f"js_retval = fdn_{out.type.nick}_to_value (env, {storage_prefix}{out.name});"
+        return (f"if ({storage_prefix}retval)" + "\n"
+                + f"  {convert}" + "\n"
+                + "else" + "\n"
+                + "  napi_get_null (env, &js_retval);")
     if method.return_value is not None:
         custom = method.customizations
         if custom is not None and custom.return_cconversion is not None:

src/frida_bindgen/model.py

@@ -39,6 +39,13 @@ class Model(core.Model):
 
 
 class ObjectType(core.ObjectType):
+    @cached_property
+    def methods(self) -> List["Method"]:
+        return [
+            m for m in super().methods
+            if not m.out_parameters or m.optional_out_parameter is not None
+        ]
+
     @cached_property
     def js_name(self) -> str:
         custom = self.customizations
@@ -211,8 +218,12 @@ class Method(core.Method):
 
     @cached_property
     def prefixed_return_typing(self) -> str:
-        retval = self.return_value
-        typing = retval.typing if retval is not None else "void"
+        out = self.optional_out_parameter
+        if out is not None:
+            typing = f"{self.object_type.model.resolve_js_type(out.type)} | null"
+        else:
+            retval = self.return_value
+            typing = retval.typing if retval is not None else "void"
         return f"Promise<{typing}>" if self.is_async else typing
 
     @property
@@ -559,6 +570,7 @@ def _make_class(
     type_struct,
     parent,
     constructors,
+    functions,
     methods,
     properties,
     signals,
@@ -573,6 +585,7 @@ def _make_class(
         type_struct,
         parent,
         constructors,
+        functions,
         methods,
         properties,
         signals,
@@ -590,6 +603,7 @@ def _make_interface(
     type_struct,
     parent,
     constructors,
+    functions,
     methods,
     properties,
     signals,
@@ -603,6 +617,7 @@ def _make_interface(
         type_struct,
         parent,
         constructors,
+        functions,
         methods,
         properties,
         signals,