Log outputs, not task messages, for unmatched prerequisites

cylc/flow/task_pool.py

@@ -1672,9 +1672,15 @@ def _get_task_proxy_db_outputs(
                     itask.state.outputs.set_completed_by_msg(msg)
         return itask
 
-    def _standardise_prereqs(self, prereqs: 'List[str]') -> 'List[Tokens]':
-        """Convert prerequisites to task output messages."""
-        _prereqs = []
+    def _standardise_prereqs(
+        self, prereqs: 'List[str]'
+    ) -> 'Dict[Tokens, str]':
+        """Convert prerequisites to a map of task messages: outputs.
+
+        (So satsify_me logs failures)
+
+        """
+        _prereqs = {}
         for prereq in prereqs:
             pre = Tokens(prereq, relative=True)
             # add implicit "succeeded"; convert "succeed" to "succeeded" etc.
@@ -1690,12 +1696,13 @@ def _standardise_prereqs(self, prereqs: 'List[str]') -> 'List[Tokens]':
                 LOG.warning(
                     f"output {pre.relative_id_with_selectors} not found")
                 continue
-            _prereqs.append(
+            _prereqs[
                 pre.duplicate(
                     task_sel=msg,
                     cycle=standardise_point_string(pre['cycle'])
                 )
-            )
+            ] = prereq
+
         return _prereqs
 
     def _standardise_outputs(
@@ -1839,11 +1846,18 @@ def _set_prereqs_itask(
         if prereqs == ["all"]:
             itask.state.set_all_satisfied()
         else:
-            if not itask.satisfy_me(
-                self._standardise_prereqs(prereqs)
-            ):
+            # Attempt to set the given presrequisites.
+            # Log any that aren't valid for the task.
+            presus = self._standardise_prereqs(prereqs)
+            unmatched = itask.satisfy_me(list(presus.keys()))
+            for task_msg in unmatched:
+                LOG.warning(
+                    f"{itask.identity} does not depend on"
+                    f' "{presus[task_msg]}"'
+                )
+            if len(unmatched) == len(prereqs):
+                # No prereqs matched.
                 return False
-
         if (
             self.runahead_limit_point is not None
             and itask.point <= self.runahead_limit_point

cylc/flow/task_proxy.py

@@ -26,7 +26,6 @@
     Counter as TypingCounter,
     Dict,
     List,
-    Iterable,
     Optional,
     Set,
     TYPE_CHECKING,
@@ -536,23 +535,19 @@ def state_reset(
 
         return False
 
-    def satisfy_me(self, outputs: 'Iterable[Tokens]') -> bool:
-        """Try to satisfy my prerequisites with given outputs.
+    def satisfy_me(
+        self, task_messages: 'List[Tokens]'
+    ) -> 'Set[Tokens]':
+        """Try to satisfy my prerequisites with given output messages.
 
-        The output strings are of the form "cycle/task:message"
-        Log a warning for outputs that I don't depend on.
+        The task output messages are of the form "cycle/task:message"
+        Log a warning for messages that I don't depend on.
 
-        Return True if any match, else False.
+        Return a set of unmatched task messages.
 
         """
-        used = self.state.satisfy_me(outputs)
-        for output in set(outputs) - used:
-            # Note this logs the task message not the output.
-            LOG.warning(
-                f"{self.identity} does not depend on"
-                f' "{output.relative_id_with_selectors}"'
-            )
-        return bool(used)
+        used = self.state.satisfy_me(task_messages)
+        return set(task_messages) - used
 
     def clock_expire(self) -> bool:
         """Return True if clock expire time is up, else False."""

tests/integration/test_task_pool.py

@@ -1352,7 +1352,7 @@ async def test_set_prereqs(
         schd.pool.set_prereqs_and_outputs(
             ["20400101T0000Z/qux"], None, ["20400101T0000Z/foo:a"], ['all'])
         assert log_filter(
-            log, contains='20400101T0000Z/qux does not depend on "20400101T0000Z/foo:drugs and money"')
+            log, contains='20400101T0000Z/qux does not depend on "20400101T0000Z/foo:a"')
 
         # it should not add 20400101T0000Z/qux to the pool
         assert (