Merge pull request #1367 from lf-lang/rust.synchronous-physical-schedule

Support scheduling physical actions synchronously

org.lflang/src/org/lflang/generator/rust/RustReactorEmitter.kt

@@ -390,7 +390,7 @@ ${"             |        "..declareChildConnections()}
                 else                                   -> "&$rsRuntime::ReadablePort<$dataType>" // note: a reference
             }
             is TimerData  -> "&${toType()}"
-            is ActionData -> if (isLogical && kind == DepKind.Effects) "&mut ${toType()}" else "&${toType()}"
+            is ActionData -> if (kind == DepKind.Effects) "&mut ${toType()}" else "&${toType()}"
         }
 
     /**

test/Rust/src/PhysicalActionCanBeScheduledSynchronously.lf

@@ -0,0 +1,28 @@
+// Tests that physical actions can be scheduled like logical actions within the
+// body of reactions.
+target Rust
+
+main reactor {
+    physical action act: u32
+
+    state count: u32
+
+    reaction(startup) -> act {=
+        ctx.schedule(act, Asap);
+        ctx.schedule(act, after!(20 ms));
+    =}
+
+    reaction(act) {=
+        println!("---- Invocation at {}", ctx.get_tag());
+        self.count += 1;
+
+        // If the physical time is used then it is unlikely to be
+        // exactly TO + 20 ms.
+        assert_ne!(ctx.get_elapsed_logical_time(), delay!(20 ms));
+    =}
+
+    reaction(shutdown) {=
+        assert_eq!(self.count, 2);
+        println!("success");
+    =}
+}

test/Rust/src/README.md

@@ -55,6 +55,7 @@ This is not exhaustive. Ideally each of those bullet points would have a test ca
   - [x] `PhysicalActionWithKeepalive.lf`: keepalive option should keep the scheduler alive when there are async threads which can send notifications
   - [x] `PhysicalActionWakesSleepingScheduler.lf`: a physical action triggered during a period of idleness of the scheduler should wake it timely
   - [x] `PhysicalActionKeepaliveIsSmart.lf`: keepalive option doesn't keep the program alive if live threads do not have a reference to the scheduler
+  - [x] `PhysicalActionCanBeScheduledSynchronously.lf`: physical actions do not need to be carried by an asynchronous thread to be scheduled. When they are scheduled within a reaction, they still use physical time and not logical time.
   - [ ] todo does shutdown abort async threads or not?
 - [x] timers
   - [x] `TimerDefaults.lf`: timer with all params defaulted (`timer t;`) is non-periodic and has offset zero