feat: add handling for extension range options

src/parse.js

@@ -144,7 +144,24 @@ function parse(source, root, options) {
             else
                 target.push([ start = parseId(next()), skip("to", true) ? parseId(next()) : start ]);
         } while (skip(",", true));
-        skip(";");
+        var dummy = {options: undefined};
+        dummy.setOption = function(name, value) {
+          if (this.options === undefined) this.options = {};
+          this.options[name] = value;
+        };
+        ifBlock(
+            dummy,
+            function parseRange_block(token) {
+              /* istanbul ignore else */
+              if (token === "option") {
+                parseOption(dummy, token);  // skip
+                skip(";");
+              } else
+                throw illegal(token);
+            },
+            function parseRange_line() {
+              parseInlineOptions(dummy);  // skip
+            });
     }
 
     function parseNumber(token, insideTryCatch) {

tests/data/google/protobuf/descriptor.proto

@@ -101,6 +101,8 @@ message DescriptorProto {
   message ExtensionRange {
     optional int32 start = 1;
     optional int32 end = 2;
+
+    optional ExtensionRangeOptions options = 3;
   }
   repeated ExtensionRange extension_range = 5;
 
@@ -121,6 +123,63 @@ message DescriptorProto {
   repeated string reserved_name = 10;
 }
 
+
+message ExtensionRangeOptions {
+  // The parser stores options it doesn't recognize here. See above.
+  repeated UninterpretedOption uninterpreted_option = 999;
+
+  message Declaration {
+    // The extension number declared within the extension range.
+    optional int32 number = 1;
+
+    // The fully-qualified name of the extension field. There must be a leading
+    // dot in front of the full name.
+    optional string full_name = 2;
+
+    // The fully-qualified type name of the extension field. Unlike
+    // Metadata.type, Declaration.type must have a leading dot for messages
+    // and enums.
+    optional string type = 3;
+
+    // If true, indicates that the number is reserved in the extension range,
+    // and any extension field with the number will fail to compile. Set this
+    // when a declared extension field is deleted.
+    optional bool reserved = 5;
+
+    // If true, indicates that the extension must be defined as repeated.
+    // Otherwise the extension must be defined as optional.
+    optional bool repeated = 6;
+
+    reserved 4;  // removed is_repeated
+  }
+
+  // For external users: DO NOT USE. We are in the process of open sourcing
+  // extension declaration and executing internal cleanups before it can be
+  // used externally.
+  repeated Declaration declaration = 2 [retention = RETENTION_SOURCE];
+
+  // The verification state of the extension range.
+  enum VerificationState {
+    // All the extensions of the range must be declared.
+    DECLARATION = 0;
+    UNVERIFIED = 1;
+  }
+
+  // The verification state of the range.
+  // TODO(b/278783756): flip the default to DECLARATION once all empty ranges
+  // are marked as UNVERIFIED.
+  optional VerificationState verification = 3
+      [default = UNVERIFIED, retention = RETENTION_SOURCE];
+
+  // Clients can define custom options in extensions of this message. See above.
+  // BEGIN GOOGLE-INTERNAL
+  // Extension numbers > 530,000,000 must be forward-declared in
+  // google3/third_party/protobuf/extdecl_extension_range_options.h. See
+  // go/extension-declaration-reserved-numbers for more information.
+  // END GOOGLE-INTERNAL
+  extensions 1000 to max;
+}
+
 // Describes a field within a message.
 message FieldDescriptorProto {
   enum Type {
@@ -813,4 +872,4 @@ message GeneratedCodeInfo {
     // the last relevant byte (so the length of the text = end - begin).
     optional int32 end = 4;
   }
-}
+}

tests/data/uncommon.proto

@@ -47,6 +47,13 @@ message Test2 {
     extend Test;
     extend Test{};
     extend Test{required int32 a=1;} // not validated by the parser
+    extend Test{Test inner_ext=1000;} // not validated by the parser
+
+    extensions 1000 to 1999 [declaration = {
+        number: 1000
+        full_name: 'uncommon.Test.inner_ext'
+        type: 'uncommon.Test'
+    }];
 };
 
 enum Test3;