compiler, testing: Build System for Compilation

The compilation code was written as a precursor for implementation
with macros. The updates in this commit make the switch.

There is still plenty to do:

1. Comment Walker.
2. Comment Macros.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Tests/p4rseTests/ControlCompilerTests.swift

@@ -107,6 +107,36 @@ import P4Lang
   #expect(#RequireOkResult(Program.Compile(simple_parser_declaration)))
 }
 
+@Test func test_simple_control_declaration_with_multiple_tables() async throws {
+  let simple_parser_declaration = """
+    control simple(bool x, bool y, bool a, bool b) {
+      action a() {
+      }
+      table t {
+        key = {
+          x: exact;
+          y: exact;
+        }
+      }
+      table u {
+        key = {
+          a: exact;
+          b: exact;
+        }
+      }
+      apply {
+      }
+    };
+    """
+  #expect(
+    #RequireErrorResult(
+      Error(
+        withMessage: "{0, 215}: More than one table in control declaration"
+      ),
+      Program.Compile(simple_parser_declaration))
+  )
+}
+
 @Test func test_simple_control_declaration_with_action_using_parameter() async throws {
   let simple_parser_declaration = """
     control simple(bool x, bool y) {
@@ -150,4 +180,36 @@ import P4Lang
       ),
       Program.Compile(simple_parser_declaration))
   )
+}
+
+@Test func test_simple_control_declaration_with_element_after_apply() async throws {
+  let simple_parser_declaration = """
+    control simple(bool x, bool y) {
+      action a(int z) {
+        z = false;
+      }
+      table t {
+        key = {
+          x: exact;
+          y: exact;
+        }
+      }
+      apply {
+      }
+      table x {
+        key = {
+          x: exact;
+          y: exact;
+        }
+      }
+    };
+    """
+  #expect(
+    #RequireErrorResult(
+      Error(
+        withMessage:
+          "Could not compile the P4 program"
+      ),
+      Program.Compile(simple_parser_declaration))
+  )
 }

Tests/p4rseTests/SupportTests/Macros.swift

@@ -0,0 +1,51 @@
+// p4rse, Copyright 2026, Will Hawkins
+//
+// This file is part of p4rse.
+//
+// This file is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+import Common
+import Foundation
+import Macros
+import P4Lang
+import P4Runtime
+import SwiftTreeSitter
+import Testing
+import TreeSitter
+import TreeSitterP4
+
+@testable import Macros
+
+func wrapper_test_mustor() -> Int {
+    let x: Int? = 2
+    var i = 0
+    #MustOr(result: i, thing: x, or: 1)
+    return i
+}
+
+func wrapper_test_mustor_none() -> Int {
+    let x: Int? = .none
+    var i = 0
+    #MustOr(result: i, thing: x, or: 1)
+    return i
+}
+
+
+@Test func test_mustor() async throws {
+    #expect(wrapper_test_mustor() == 2)
+}
+
+@Test func test_mustor_none() async throws {
+    #expect(wrapper_test_mustor_none() == 1)
+}