Rutefig/194 add check that the signal is in the circuit (privacy-scal…

…ing-explorations#198)

Adds a check if the signal that is trying to be exposed is already in
the circuit or not, this way the user will always know if is trying to
expose a non existing signal.

src/sbpir/mod.rs

@@ -119,6 +119,19 @@ impl<F, TraceArgs> SBPIR<F, TraceArgs> {
     pub fn expose(&mut self, signal: Queriable<F>, offset: ExposeOffset) {
         match signal {
             Queriable::Forward(..) | Queriable::Shared(..) => {
+                let existing_forward_signal = self
+                    .forward_signals
+                    .clone()
+                    .iter()
+                    .any(|s| s.uuid() == signal.uuid());
+                let existing_shared_signal = self
+                    .shared_signals
+                    .clone()
+                    .iter()
+                    .any(|s| s.uuid() == signal.uuid());
+                if !existing_forward_signal && !existing_shared_signal {
+                    panic!("Signal not found in forward signals.");
+                }
                 self.exposed.push((signal, offset));
             }
             _ => panic!("Can only expose forward and shared signals."),
@@ -530,4 +543,37 @@ mod tests {
         let circuit: SBPIR<i32, i32> = SBPIR::default();
         assert!(circuit.q_enable);
     }
+
+    #[test]
+    #[should_panic]
+    fn test_expose_non_existing_signal() {
+        let mut circuit: SBPIR<i32, i32> = SBPIR::default();
+        let signal = Queriable::Forward(
+            ForwardSignal::new_with_phase(0, "signal".to_string()),
+            false,
+        );
+        let offset = ExposeOffset::First;
+
+        circuit.expose(signal, offset);
+    }
+
+    #[test]
+    fn test_expose_forward_signal() {
+        let mut circuit: SBPIR<i32, i32> = SBPIR::default();
+        let signal = circuit.add_forward("signal", 0);
+        let offset = ExposeOffset::Last;
+        assert_eq!(circuit.exposed.len(), 0);
+        circuit.expose(Queriable::Forward(signal, false), offset);
+        assert_eq!(circuit.exposed.len(), 1);
+    }
+
+    #[test]
+    fn test_expose_shared_signal() {
+        let mut circuit: SBPIR<i32, i32> = SBPIR::default();
+        let signal = circuit.add_shared("signal", 0);
+        let offset = ExposeOffset::Last;
+        assert_eq!(circuit.exposed.len(), 0);
+        circuit.expose(Queriable::Shared(signal, 10), offset);
+        assert_eq!(circuit.exposed.len(), 1);
+    }
 }