Handle unknown fields part of a oneof

protobuf/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 1.0.2
+
+* Handle cases where a field that is part of a oneof is removed by the
+  protobuf aware treeshaker.
+
 ## 1.0.1
 
 * Fix issue with the non-json name of a field (`protoName`) not being set correctly.

protobuf/lib/src/protobuf/coded_buffer.dart

@@ -42,6 +42,7 @@ void _mergeFromCodedBufferReader(
     }
 
     if (fi == null || !_wireTypeMatches(fi.type, wireType)) {
+      fs._updateOneOfCase(tagNumber);
       if (!fs._ensureUnknownFields().mergeFieldFromBuffer(tag, input)) {
         return;
       }

protobuf/lib/src/protobuf/field_set.dart

@@ -265,8 +265,9 @@ class _FieldSet {
       }
     }
 
-    // neither a regular field nor an extension.
-    // TODO(skybrian) throw?
+    if (_hasUnknownFields) {
+      _unknownFields._clearField(tagNumber);
+    }
   }
 
   /// Sets a non-repeated field with error-checking.
@@ -342,14 +343,17 @@ class _FieldSet {
     return newValue;
   }
 
-  /// Sets a non-extended field and fires events.
-  void _setNonExtensionFieldUnchecked(FieldInfo fi, value) {
-    int tag = fi.tagNumber;
-    int oneofIndex = _meta.oneofs[tag];
+  void _updateOneOfCase(int newTagnumber) {
+    int oneofIndex = _meta.oneofs[newTagnumber];
     if (oneofIndex != null) {
       _clearField(_oneofCases[oneofIndex]);
-      _oneofCases[oneofIndex] = tag;
+      _oneofCases[oneofIndex] = newTagnumber;
     }
+  }
+
+  /// Sets a non-extended field and fires events.
+  void _setNonExtensionFieldUnchecked(FieldInfo fi, value) {
+    _updateOneOfCase(fi.tagNumber);
 
     // It is important that the callback to the observers is not moved to the
     // beginning of this method but happens just before the value is set.

protobuf/lib/src/protobuf/generated_message.dart

@@ -300,8 +300,11 @@ abstract class GeneratedMessage {
 
   /// Clears the contents of a given field.
   ///
-  /// If it's an extension field, the Extension will be kept.
-  /// The tagNumber should be a valid tag or extension.
+  /// If it's an extension field, the value will be removed, but the Extension
+  /// will be kept.
+  ///
+  /// If the tagNumber is present as an unknown field, that field will be
+  /// removed.
   void clearField(int tagNumber) => _fieldSet._clearField(tagNumber);
 
   int $_whichOneof(int oneofIndex) => _fieldSet._oneofCases[oneofIndex] ?? 0;

protobuf/lib/src/protobuf/unknown_field_set.dart

@@ -31,8 +31,15 @@ class UnknownFieldSet {
 
   UnknownFieldSetField getField(int tagNumber) => _fields[tagNumber];
 
+  /// Returns `true` if [tagNumber] is set in [this].
   bool hasField(int tagNumber) => _fields.containsKey(tagNumber);
 
+  /// Removes [tagNumber] from [this].
+  ///
+  /// Does nothing if [tagNumber] is unset.
+  void _clearField(int tagNumber) => _fields.remove(tagNumber);
+
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void addField(int number, UnknownFieldSetField field) {
     _ensureWritable('addField');
     _checkFieldNumber(number);
@@ -49,6 +56,10 @@ class UnknownFieldSet {
       ..groups.addAll(field.groups);
   }
 
+  /// Merges the field following [tag] into [this].
+  ///
+  /// Returns `false` if the tag is the end of a group. `true` otherwise.
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   bool mergeFieldFromBuffer(int tag, CodedBufferReader input) {
     _ensureWritable('mergeFieldFromBuffer');
     int number = getTagFieldNumber(tag);
@@ -76,6 +87,7 @@ class UnknownFieldSet {
     }
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeFromCodedBufferReader(CodedBufferReader input) {
     _ensureWritable('mergeFromCodedBufferReader');
     while (true) {
@@ -86,6 +98,7 @@ class UnknownFieldSet {
     }
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeFromUnknownFieldSet(UnknownFieldSet other) {
     _ensureWritable('mergeFromUnknownFieldSet');
     for (int key in other._fields.keys) {
@@ -99,26 +112,31 @@ class UnknownFieldSet {
     }
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeFixed32Field(int number, int value) {
     _ensureWritable('mergeFixed32Field');
     _getField(number).addFixed32(value);
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeFixed64Field(int number, Int64 value) {
     _ensureWritable('mergeFixed64Field');
     _getField(number).addFixed64(value);
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeGroupField(int number, UnknownFieldSet value) {
     _ensureWritable('mergeGroupField');
     _getField(number).addGroup(value);
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeLengthDelimitedField(int number, List<int> value) {
     _ensureWritable('mergeLengthDelimitedField');
     _getField(number).addLengthDelimited(value);
   }
 
+  // TODO(sigurdm): Does not update oneofs. Consider deprecating.
   void mergeVarintField(int number, Int64 value) {
     _ensureWritable('mergeVarintField');
     _getField(number).addVarint(value);

protobuf/pubspec.yaml

@@ -1,5 +1,5 @@
 name: protobuf
-version: 1.0.1
+version: 1.0.2
 author: Dart Team <[email protected]>
 description: >
   Runtime library for protocol buffers support.