Merge pull request #540 from pyiron/valid_connection_refactor

Refactor connection validity

pyiron_workflow/channels.py

@@ -118,12 +118,6 @@ def full_label(self) -> str:
         """A label combining the channel's usual label and its owner's semantic path"""
         return f"{self.owner.full_label}.{self.label}"
 
-    @abstractmethod
-    def _valid_connection(self, other: object) -> bool:
-        """
-        Logic for determining if a connection is valid.
-        """
-
     def connect(self, *others: ConjugateType) -> None:
         """
         Form a connection between this and one or more other channels.
@@ -146,22 +140,30 @@ def connect(self, *others: ConjugateType) -> None:
         for other in others:
             if other in self.connections:
                 continue
-            elif self._valid_connection(other):
-                # Prepend new connections
-                # so that connection searches run newest to oldest
-                self.connections.insert(0, other)
-                other.connections.insert(0, self)
-            else:
-                if isinstance(other, self.connection_conjugate()):
+            elif isinstance(other, self.connection_conjugate()):
+                if self._valid_connection(other):
+                    # Prepend new connections
+                    # so that connection searches run newest to oldest
+                    self.connections.insert(0, other)
+                    other.connections.insert(0, self)
+                else:
                     raise ChannelConnectionError(
                         self._connection_conjugate_failure_message(other)
                     ) from None
-                else:
-                    raise TypeError(
-                        f"Can only connect to {self.connection_conjugate()} "
-                        f"objects, but {self.full_label} ({self.__class__}) "
-                        f"got {other} ({type(other)})"
-                    )
+            else:
+                raise TypeError(
+                    f"Can only connect to {self.connection_conjugate()} "
+                    f"objects, but {self.full_label} ({self.__class__}) "
+                    f"got {other} ({type(other)})"
+                )
+
+    def _valid_connection(self, other: ConjugateType) -> bool:
+        """
+        Logic for determining if a connection to a conjugate partner is valid.
+
+        Override in child classes as necessary.
+        """
+        return True
 
     def _connection_conjugate_failure_message(self, other: ConjugateType) -> str:
         return (
@@ -466,21 +468,18 @@ def _value_is_data(self) -> bool:
     def _has_hint(self) -> bool:
         return self.type_hint is not None
 
-    def _valid_connection(self, other: object) -> bool:
-        if isinstance(other, self.connection_conjugate()):
-            if self._both_typed(other):
-                out, inp = self._figure_out_who_is_who(other)
-                if not inp.strict_hints:
-                    return True
-                else:
-                    return type_hint_is_as_or_more_specific_than(
-                        out.type_hint, inp.type_hint
-                    )
-            else:
-                # If either is untyped, don't do type checking
+    def _valid_connection(self, other: DataChannel) -> bool:
+        if self._both_typed(other):
+            out, inp = self._figure_out_who_is_who(other)
+            if not inp.strict_hints:
                 return True
+            else:
+                return type_hint_is_as_or_more_specific_than(
+                    out.type_hint, inp.type_hint
+                )
         else:
-            return False
+            # If either is untyped, don't do type checking
+            return True
 
     def _connection_conjugate_failure_message(self, other: DataChannel) -> str:
         msg = super()._connection_conjugate_failure_message(other)
@@ -599,9 +598,6 @@ class SignalChannel(FlavorChannel[SignalType], ABC):
     def __call__(self) -> None:
         pass
 
-    def _valid_connection(self, other: object) -> bool:
-        return isinstance(other, self.connection_conjugate())
-
 
 class BadCallbackError(ValueError):
     pass