Fix Target.instruction_supported to correctly evaluate targets with n…

…um_qubits==None (restore pre-Rust-migration behavior)
ElePT · Jan 13, 2025 · 4e9194f · 4e9194f
1 parent 8d8da66
commit 4e9194f
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Showing 2 changed files with 14 additions and 2 deletions.
diff --git a/crates/accelerate/src/target_transpiler/mod.rs b/crates/accelerate/src/target_transpiler/mod.rs
@@ -1163,6 +1163,7 @@ impl Target {
                         match obj {
                             TargetOperation::Variadic(_) => {
                                 return qargs.is_none()
+                                    || self.num_qubits == None
                                     || _qargs.iter().all(|qarg| {
                                         qarg.index() <= self.num_qubits.unwrap_or_default()
                                     }) && qarg_set.len() == _qargs.len();
@@ -1171,7 +1172,8 @@ impl Target {
                                 let qubit_comparison = obj.operation.num_qubits();
                                 return qubit_comparison == _qargs.len() as u32
                                     && _qargs.iter().all(|qarg| {
-                                        qarg.index() < self.num_qubits.unwrap_or_default()
+                                        (qarg.index() < self.num_qubits.unwrap_or_default())
+                                            || self.num_qubits == None
                                     });
                             }
                         }
@@ -1182,6 +1184,7 @@ impl Target {
                     match obj {
                         TargetOperation::Variadic(_) => {
                             return qargs.is_none()
+                                || self.num_qubits == None
                                 || _qargs.iter().all(|qarg| {
                                     qarg.index() <= self.num_qubits.unwrap_or_default()
                                 }) && qarg_set.len() == _qargs.len();
@@ -1190,7 +1193,8 @@ impl Target {
                             let qubit_comparison = obj.operation.num_qubits();
                             return qubit_comparison == _qargs.len() as u32
                                 && _qargs.iter().all(|qarg| {
-                                    qarg.index() < self.num_qubits.unwrap_or_default()
+                                    (qarg.index() < self.num_qubits.unwrap_or_default())
+                                        || self.num_qubits == None
                                 });
                         }
                     }

diff --git a/test/python/transpiler/test_target.py b/test/python/transpiler/test_target.py
@@ -1169,6 +1169,14 @@ def test_instruction_supported_no_args(self):
     def test_instruction_supported_no_operation(self):
         self.assertFalse(self.ibm_target.instruction_supported(qargs=(0,), parameters=[math.pi]))
 
+    def test_instruction_supported_no_qubits(self):
+        """Checks that instruction supported works when target.num_qubits is None."""
+        target = Target.from_configuration(["u", "cx", "rxx"])
+        self.assertTrue(target.instruction_supported("u", (0,)))
+        self.assertTrue(target.instruction_supported("cx", (0,1)))
+        self.assertTrue(target.instruction_supported("cx", None))
+        self.assertTrue(target.instruction_supported("rxx", (2,3)))
+
     def test_target_serialization_preserve_variadic(self):
         """Checks that variadics are still seen as variadic after serialization"""