syntax = "proto2";

package test;

message Message1 {
    optional int32 value = 1;
    extensions 100 to 150;
}

extend Message1 {
    optional int32 extension1 = 100;
}

extend Message1 {
    optional int32 value = 102;
}

message Message2 {
    extend Message1 {
        optional Message2 extension2 = 101;
    }
    optional int32 value = 1;
}