chore: add grammar tests

Author: sofisl

src/parse.js

@@ -378,6 +378,8 @@ function parse(source, root, options) {
 
                 case "optional":
                     /* istanbul ignore if */
+                    // console.log('in optional?')
+                    // console.log('')
                     if (isProto3) {
                         parseField(type, "proto3_optional");
                     } else if (edition) {

tests/feature_grammar.js

@@ -0,0 +1,33 @@
+var tape = require("tape");
+
+var protobuf = require("..");
+
+var protoEditionsRequired = `edition = "2023";
+    message A {\
+        required uint32 a = 1;\
+    }`;
+var protoEditionsOptional = `edition = "2023";
+    message A {\
+        optional uint32 a = 1;\
+    }`;
+
+var protoEditionsGroup = `edition = "2023";
+    message A {\
+        group uint32 a = 1;\
+    }`;
+
+tape.test("editions grammar", function(test) {
+    test.throws(function() {
+        protobuf.parse(protoEditionsRequired);
+    }, Error, "Error: illegal token 'required'");
+
+    test.throws(function() {
+        protobuf.parse(protoEditionsOptional);
+    }, Error, "Error: illegal token 'optional'");
+
+    test.throws(function() {
+        protobuf.parse(protoEditionsGroup);
+    }, Error, "Error: illegal token 'group'");
+
+    test.end();
+});