diff --git a/protobuf-codegen/src/extensions.rs b/protobuf-codegen/src/extensions.rs
index d3b417a46..b463dddd3 100644
--- a/protobuf-codegen/src/extensions.rs
+++ b/protobuf-codegen/src/extensions.rs
@@ -53,7 +53,7 @@ impl<'a> ExtGen<'a> {
         };
         let field_type = format!("::protobuf::ext::ExtField{}", suffix);
         w.pub_const(
-            self.field.get_name(), // TODO: escape
+            &self.field.rust_name(),
             &format!(
                 "{}<{}, {}>",
                 field_type,
diff --git a/protobuf-codegen/src/field.rs b/protobuf-codegen/src/field.rs
index bad0c6876..5bae17500 100644
--- a/protobuf-codegen/src/field.rs
+++ b/protobuf-codegen/src/field.rs
@@ -474,7 +474,7 @@ impl<'a> FieldGen<'a> {
         FieldGen {
             root_scope: root_scope,
             syntax: field.message.get_scope().file_scope.syntax(),
-            rust_name: field.rust_name(),
+            rust_name: field.field.rust_name(),
             proto_type: field.field.get_field_type(),
             wire_type: field_type_wire_type(field.field.get_field_type()),
             enum_default_value: enum_default_value,
diff --git a/protobuf-test/src/common/v2/test_ident_pb.proto b/protobuf-test/src/common/v2/test_ident_pb.proto
index 91ade19a9..280e59bb8 100644
--- a/protobuf-test/src/common/v2/test_ident_pb.proto
+++ b/protobuf-test/src/common/v2/test_ident_pb.proto
@@ -1,5 +1,7 @@
 syntax = "proto2";
 
+import "google/protobuf/descriptor.proto";
+
 package test_ident;
 
 // rust types defined in prelude
@@ -65,3 +67,7 @@ message MessageReferencesEnumWithDefaultValueReserved {
         EnumWithDefaultValueReserved e4 = 4;
     }
 }
+
+extend google.protobuf.EnumValueOptions {
+    optional string type = 51234;
+}
diff --git a/protobuf/src/descriptorx.rs b/protobuf/src/descriptorx.rs
index 6d8675821..cbc71d5fa 100644
--- a/protobuf/src/descriptorx.rs
+++ b/protobuf/src/descriptorx.rs
@@ -491,6 +491,19 @@ impl<'a> WithScope<'a> for MessageOrEnumWithScope<'a> {
     }
 }
 
+pub trait FieldDescriptorProtoExt {
+    fn rust_name(&self) -> String;
+}
+
+impl FieldDescriptorProtoExt for FieldDescriptorProto {
+    fn rust_name(&self) -> String {
+        if rust::is_rust_keyword(self.get_name()) {
+            format!("field_{}", self.get_name())
+        } else {
+            self.get_name().to_string()
+        }
+    }
+}
 
 #[derive(Clone)]
 pub struct FieldWithContext<'a> {
@@ -524,12 +537,9 @@ impl<'a> FieldWithContext<'a> {
     }
 
     // field name in generated code
+    #[deprecated]
     pub fn rust_name(&self) -> String {
-        if rust::is_rust_keyword(self.field.get_name()) {
-            format!("field_{}", self.field.get_name())
-        } else {
-            self.field.get_name().to_string()
-        }
+        self.field.rust_name()
     }
 
     // From field to file root