Parse Struct Declarations

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

Tests/p4rseTests/Declarations.swift

@@ -0,0 +1,53 @@
+// 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 P4Runtime
+import P4Lang
+import SwiftTreeSitter
+import Testing
+import TreeSitter
+import TreeSitterP4
+
+@testable import P4Compiler
+
+@Test func test_struct_declaration_and_field_write() async throws {
+  let simple_parser_declaration = """
+      struct Testing {
+        bool yesno;
+        int count;
+      };
+      parser main_parser() {
+        state start {
+          Testing ts;
+          ts.yesno = true;
+          bool where_to = ts.yesno;
+          transition select (where_to) {
+            true: accept;
+            false: reject;
+          };
+        }
+      };
+    """
+  let program = try #UseOkResult(
+    Program.Compile(simple_parser_declaration))
+  let runtime = try #UseOkResult(P4Runtime.ParserRuntime.create(program: program))
+  let (state_result, _) = try! #UseOkResult(runtime.run())
+  #expect(state_result == P4Lang.accept)
+}

Tests/p4rseTests/ParserCompilerTests.swift

@@ -61,22 +61,6 @@ import P4Lang
   #expect(state.statements.count == 1)
 }
 
-@Test func test_simple_compilation_with_instantiation() async throws {
-  let simple_parser_declaration = """
-    parser main_parser() {
-       state start {
-           true;
-           false;
-           transition start;
-       }
-    };
-    bool() main;
-    """
-
-  let program = try #UseOkResult(Program.Compile(simple_parser_declaration))
-  #expect(#RequireOkResult(program.find_parser(withName: Identifier(name: "main_parser"))))
-}
-
 @Test func test_invalid_transition_expression_keyset_expressions() async throws {
   let simple_parser_declaration = """
     parser main_parser() {
@@ -114,5 +98,5 @@ import P4Lang
     #RequireErrorResult<(EvaluatableStatement, CompilerContext)>(
       Error(withMessage: "{2, 154}: Did not find assignment statement"),
       ParserAssignmentStatement.Compile( // Note: Calling ParserAssignmentStatement compilation directly.
-        node: result.rootNode!, withContext: CompilerContext(withNames: VarTypeScopes()))))
+        node: result.rootNode!, withContext: CompilerContext(withInstances: VarTypeScopes()))))
 }