fix: test for const arguments

src/Quasar.jl

@@ -615,7 +615,7 @@ function parse_expression(tokens::Vector{Tuple{Int64, Int32, Token}}, stack, sta
         token_name = parse_classical_type(pushfirst!(tokens, start_token), stack, start, qasm)
     elseif start_token[end] ∈ (string_token, integer, float, hex, oct, bin, irrational, dot, boolean)
         token_name = parse_literal(pushfirst!(tokens, start_token), stack, start, qasm)
-    elseif start_token[end] ∈ (mutable, readonly)
+    elseif start_token[end] ∈ (mutable, readonly, const_token)
         token_name = parse_identifier(start_token, qasm)
     elseif start_token[end] == dim_token
         raw_dim = qasm[start_token[1]:start_token[1]+start_token[2]-1]
@@ -659,7 +659,7 @@ function parse_expression(tokens::Vector{Tuple{Int64, Int32, Token}}, stack, sta
             stop = parse_expression(tokens, stack, start, qasm)::QasmExpression
         end
         expr = QasmExpression(:range, QasmExpression[start, step, stop])
-    elseif next_token[end] == classical_type && start_token[end] ∈ (mutable, readonly)
+    elseif next_token[end] == classical_type && start_token[end] ∈ (mutable, readonly, const_token)
         type = parse_classical_type(tokens, stack, start, qasm)
         is_mutable = (start_token[end] == mutable)
         header = is_mutable ? :classical_declaration : :const_declaration

test/test_openqasm3.jl

@@ -1229,6 +1229,28 @@ get_tol(shots::Int) = return (
         @test visitor.classical_defs["array_1"].val == [1, 2, 3, 4, 5]
         @test visitor.classical_defs["array_2"].val == collect(1:10)
     end
+    @testset "Const array argument" begin
+        qasm_string = """
+        qubit q;
+
+        def sum(const array[int[8], #dim = 1] arr) -> int {
+            int size = sizeof(arr);
+            int x = 0;
+            for int i in [0:size - 1] {
+                x += arr[i];
+            }
+            return x;
+        }
+
+        array[int, 10] arr = {9, 3, 6, 2, 2, 4, 3, 1, 12, 7};
+        int s = sum(arr);
+        rx(s*π/4) q;
+        """
+        parsed = parse_qasm(qasm_string)
+        visitor = QasmProgramVisitor()
+        visitor(parsed)
+        @test visitor.classical_defs["s"].val == sum([ 9, 3, 6, 2, 2, 4, 3, 1, 12, 7 ])
+    end
     @testset "Array ref subroutine with mutation" begin
         qasm = """
         def mutate_array(mutable array[int[8], #dim = 1] arr) {