Add EvalFuncVar binding via descriptor and drop manual rebinding

Author: dmamelin

custom_components/pyscript/eval.py

@@ -873,6 +873,15 @@ def get_ast_ctx(self):
         """Return the ast context."""
         return self.ast_ctx
 
+    def __get__(self, obj, objtype=None):
+        """Support descriptor protocol so class attributes bind to instances."""
+        if obj is None:
+            return self
+        # we use weak references when we bind the method calls to the instance inst;
+        # otherwise these self references cause the object to not be deleted until
+        # it is later garbage collected
+        return EvalFuncVarClassInst(self.func, self.ast_ctx, weakref.ref(obj))
+
     def __del__(self):
         """On deletion, stop any triggers for this function."""
         if self.func:
@@ -1983,22 +1992,6 @@ async def call_func(self, func, func_name, *args, **kwargs):
         if inspect.isclass(func) and hasattr(func, "__init__evalfunc_wrap__"):
             has_init_wrapper = getattr(func, "__init__evalfunc_wrap__") is not None
             inst = func(*args, **kwargs) if not has_init_wrapper else func()
-            #
-            # we use weak references when we bind the method calls to the instance inst;
-            # otherwise these self references cause the object to not be deleted until
-            # it is later garbage collected
-            #
-            inst_weak = weakref.ref(inst)
-            for name in dir(inst):
-                try:
-                    value = getattr(inst, name)
-                except AttributeError:
-                    # same effect as hasattr (which also catches AttributeError)
-                    # dir() may list names that aren't actually accessible attributes
-                    continue
-                if type(value) is not EvalFuncVar:
-                    continue
-                setattr(inst, name, EvalFuncVarClassInst(value.get_func(), value.get_ast_ctx(), inst_weak))
             if has_init_wrapper:
                 #
                 # since our __init__ function is async, call the renamed one

tests/test_unit_eval.py

@@ -181,6 +181,58 @@ class Color(Enum):
     ],
     [
         """
+from enum import Enum
+
+class HomeState(Enum):
+    HOME = "home"
+    AWAY = "away"
+
+    def name_and_value(self):
+        return f"{self.name}:{self.value}"
+
+[HomeState.HOME.name_and_value(), HomeState.AWAY.name_and_value()]
+""",
+        ["HOME:home", "AWAY:away"],
+    ],
+    [
+        """
+class Device:
+    def greet(self, name):
+        return f"hi {name} from {self.__class__.__name__}"
+
+d = Device()
+d.greet("Alice")
+""",
+        "hi Alice from Device",
+    ],
+    [
+        """
+def add(self, x, y=0):
+    return x + y
+
+class Calc:
+    pass
+
+Calc.add = add
+Calc().add(2, 3)
+""",
+        5,
+    ],
+    [
+        """
+class Base:
+    def tag(self):
+        return "base"
+
+class Child(Base):
+    pass
+
+Child().tag()
+""",
+        "base",
+    ],
+    [
+        """
 from dataclasses import dataclass
 
 @dataclass()