fix: mangle OpenQASM keywords (#28)

* Fix: Append '_' to the variable names that are reserved keywords

1. Fixed few existing test cases that got affected due to this change
2. Added reserved keyword list

* Add test to verify name mangling works for reserved keywords

1. Created a new file for the reserved keywords

* Change return type to tuple

* Change function signature to return new name

* Separate keywords using comments

* turn into single-liner

Co-authored-by: Lauren Capelluto <laurecap@amazon.com>

---------

Co-authored-by: Jean-Christophe Jaskula <99367153+jcjaskula-aws@users.noreply.github.com>
Co-authored-by: Ryan Shaffer <3620100+rmshaffer@users.noreply.github.com>
Co-authored-by: Lauren Capelluto <laurecap@amazon.com>

src/autoqasm/api.py

@@ -33,6 +33,7 @@
 import autoqasm.types as aq_types
 from autoqasm import errors
 from autoqasm.program.gate_calibrations import GateCalibration
+from autoqasm.reserved_keywords import sanitize_parameter_name
 from autoqasm.types import QubitIdentifierType as Qubit
 
 
@@ -323,6 +324,11 @@ def _convert_subroutine(
     with aq_program.build_program() as program_conversion_context:
         oqpy_program = program_conversion_context.get_oqpy_program()
 
+        # Iterate over list of dictionary keys to avoid runtime error
+        for key in list(kwargs):
+            new_name = sanitize_parameter_name(key)
+            kwargs[new_name] = kwargs.pop(key)
+
         if f not in program_conversion_context.subroutines_processing:
             # Mark that we are starting to process this function to short-circuit recursion
             program_conversion_context.subroutines_processing.add(f)
@@ -419,6 +425,12 @@ def _wrap_for_oqpy_subroutine(f: Callable, options: converter.ConversionOptions)
     def _func(*args, **kwargs) -> Any:
         inner_program: oqpy.Program = args[0]
         with aq_program.get_program_conversion_context().push_oqpy_program(inner_program):
+            # Bind args and kwargs to '_func' signature
+            sig = inspect.signature(_func)
+            bound_args = sig.bind(*args, **kwargs)
+            bound_args.apply_defaults()
+            args = bound_args.args
+            kwargs = bound_args.kwargs
             result = aq_transpiler.converted_call(f, args[1:], kwargs, options=options)
         inner_program.autodeclare()
         return result
@@ -441,8 +453,12 @@ def _func(*args, **kwargs) -> Any:
                 "is missing a required type hint."
             )
 
+        # Check whether 'param.name' is a reserved keyword
+        new_name = sanitize_parameter_name(param.name)
+        _func.__annotations__.pop(param.name)
+
         new_param = inspect.Parameter(
-            name=param.name,
+            name=new_name,
             kind=param.kind,
             annotation=aq_types.map_parameter_type(param.annotation),
         )

src/autoqasm/reserved_keywords.py

@@ -0,0 +1,77 @@
+# Copied from:
+# https://github.com/openqasm/openqasm/blob/main/source/grammar/qasm3Lexer.g4
+# https://github.com/openqasm/openpulse-python/blob/main/source/grammar/openpulseLexer.g4
+
+reserved_keywords = {
+    # openQASM keywords
+    "angle",
+    "array",
+    "barrier",
+    "bit",
+    "bool",
+    "box",
+    "cal",
+    "case",
+    "complex",
+    "const",
+    "creg",
+    "ctrl",
+    "default",
+    "defcal",
+    "defcalgrammar",
+    "delay",
+    "duration",
+    "durationof",
+    "end",
+    "euler",
+    "extern",
+    "false",
+    "float",
+    "gate",
+    "gphase",
+    "im",
+    "include",
+    "input",
+    "int",
+    "inv",
+    "let",
+    "OPENQASM",
+    "measure",
+    "mutable",
+    "negctrl",
+    "output",
+    "pi",
+    "pragma",
+    "qreg",
+    "qubit",
+    "readonly",
+    "reset",
+    "return",
+    "sizeof",
+    "stretch",
+    "switch",
+    "tau",
+    "true",
+    "U",
+    "uint",
+    "void",
+    # openpulse keywords
+    "frame",
+    "port",
+    "waveform",
+}
+
+
+def sanitize_parameter_name(name: str) -> str:
+    """
+    Method to modify the variable name if it is a
+    reserved keyword
+
+    Args:
+        name (str): Name of the variable to be checked
+
+    Returns:
+        str: Returns a modified 'name' that has an underscore ('_') appended to it;
+        otherwise, it returns the original 'name' unchanged
+    """
+    return f"{name}_" if name in reserved_keywords else name

test/unit_tests/autoqasm/test_api.py

@@ -16,6 +16,8 @@
 the local simulator.
 """
 
+import math
+
 import pytest
 from braket.devices import LocalSimulator
 from braket.tasks.local_quantum_task import LocalQuantumTask
@@ -1266,3 +1268,27 @@ def test(int[32] a, int[32] b) {
 test(2, 3);
 test(4, 5);"""
     assert main.build().to_ir() == expected
+
+
+def test_subroutine_call_with_reserved_keyword():
+    """Test that subroutine call works with reserved keyword as a variable name"""
+
+    @aq.subroutine
+    def make_input_state(input: int, theta: float):
+        rx(input, theta)
+        measure(input)
+
+    @aq.main(num_qubits=3)
+    def teleportation():
+        input, theta = 0, math.pi / 2
+        make_input_state(theta=theta, input=input)
+
+    expected = """OPENQASM 3.0;
+def make_input_state(int[32] input_, float[64] theta) {
+    rx(theta) __qubits__[input_];
+    bit __bit_0__;
+    __bit_0__ = measure __qubits__[input_];
+}
+qubit[3] __qubits__;
+make_input_state(0, 1.5707963267948966);"""
+    assert teleportation.build().to_ir() == expected

test/unit_tests/autoqasm/test_parameters.py

@@ -401,8 +401,8 @@ def sub(float[64] alpha, float[64] theta) {
     rx(theta) __qubits__[0];
     rx(alpha) __qubits__[1];
 }
-def rx_alpha(int[32] qubit) {
-    rx(alpha) __qubits__[qubit];
+def rx_alpha(int[32] qubit_) {
+    rx(alpha) __qubits__[qubit_];
 }
 float alpha = 0.5;
 float beta = 1.5;
@@ -427,8 +427,8 @@ def parametric(alpha: float, beta: float):
     bound_prog = parametric.build().make_bound_program({"beta": np.pi})
 
     expected = """OPENQASM 3.0;
-def rx_alpha(int[32] qubit, float[64] theta) {
-    rx(theta) __qubits__[qubit];
+def rx_alpha(int[32] qubit_, float[64] theta) {
+    rx(theta) __qubits__[qubit_];
 }
 input float alpha;
 float beta = 3.141592653589793;

test/unit_tests/autoqasm/test_program.py

@@ -95,8 +95,8 @@ def zne() -> aq.BitVar:
     def expected(scale, angle):
         return (
             """OPENQASM 3.0;
-def circuit(float[64] angle) {
-    rx(angle) __qubits__[0];
+def circuit(float[64] angle_) {
+    rx(angle_) __qubits__[0];
     cnot __qubits__[0], __qubits__[1];
 }
 output bit return_value;

test/unit_tests/autoqasm/test_types.py

@@ -309,7 +309,7 @@ def main():
         annotation_test(True)
 
     expected = """OPENQASM 3.0;
-def annotation_test(bool input) {
+def annotation_test(bool input_) {
 }
 annotation_test(true);"""
 
@@ -328,7 +328,7 @@ def main():
         annotation_test(1)
 
     expected = """OPENQASM 3.0;
-def annotation_test(int[32] input) {
+def annotation_test(int[32] input_) {
 }
 annotation_test(1);"""
 
@@ -347,7 +347,7 @@ def main():
         annotation_test(1.0)
 
     expected = """OPENQASM 3.0;
-def annotation_test(float[64] input) {
+def annotation_test(float[64] input_) {
 }
 annotation_test(1.0);"""
 
@@ -366,7 +366,7 @@ def main():
         annotation_test(1)
 
     expected = """OPENQASM 3.0;
-def annotation_test(qubit input) {
+def annotation_test(qubit input_) {
 }
 qubit[2] __qubits__;
 annotation_test(__qubits__[1]);"""
@@ -403,7 +403,7 @@ def main():
         annotation_test(a)
 
     expected = """OPENQASM 3.0;
-def annotation_test(bit input) {
+def annotation_test(bit input_) {
 }
 bit a = 1;
 annotation_test(a);"""
@@ -423,7 +423,7 @@ def main():
         annotation_test(aq.BitVar(1))
 
     expected = """OPENQASM 3.0;
-def annotation_test(bit input) {
+def annotation_test(bit input_) {
 }
 bit __bit_0__ = 1;
 annotation_test(__bit_0__);"""