wren node: untrained targets left out of the prompt, a read beside a held-back set goes on whole

backend/fluksio/flow/nodes/wren.py

@@ -445,11 +445,14 @@ class WrenNode(Node):
         threshold = 1.0
         if self.pack is not None:
             wren = _wren()
+            # A target the model never learnt is left out: shown, it is a line
+            # unlike any in training, which shifts the answers on the others.
             targets = [
                 wren.Target(
                     **t, value=_unset(t) if current.get(p) is None else current[p]
                 )
                 for p, t in self.targets.items()
+                if p not in self.untrained
             ]
             # One BLAS thread answers in about half the time for a model
             # this small. Scoped to the call, so numpy elsewhere in the
@@ -470,6 +473,9 @@ class WrenNode(Node):
             and (call.value is not None or current.get(call.target) is not None)
             for call in calls
         )
+        # A reading answered beside a set that is not written would drop the
+        # set unsaid, so the whole command goes on instead.
+        held = not self.cfg.apply and any(call.value is not None for call in calls)
         specs = {spec.port: spec for spec in [*self.input_ports, *self.output_ports]}
         writes: dict[str, Any] = {}
         actions: list[dict[str, Any]] = []
@@ -477,7 +483,7 @@ class WrenNode(Node):
         answers: list[str] = []
         for call in calls:
             spec, unit = specs[call.target], self.targets[call.target]["unit"]
-            applied = sure if call.value is None else sure and self.cfg.apply
+            applied = sure and (not held if call.value is None else self.cfg.apply)
             if call.value is None:
                 value = current.get(call.target)
                 if applied: