New versions of protobuf cause build failures

[mightybyte]

Whenever a new version of the protobuf library comes out, I get an error like the following:

   Compiling crypto-message v1.1.21 (https://github.com/mightybyte/crypto-msg-parser.git#37de71d1)
error[E0425]: cannot find value `VERSION_3_5_0` in crate `protobuf`
  --> /root/.cargo/git/checkouts/crypto-msg-parser-15bfe06dc6f1f762/37de71d/crypto-message/src/proto/message.rs:26:49
   |
26 | const _PROTOBUF_VERSION_CHECK: () = ::protobuf::VERSION_3_5_0;
   |                                                 ^^^^^^^^^^^^^ help: a constant with a similar name exists: `VERSION_3_6_0`
   |
  ::: /home/mightybyte/myproj/target/debug/build/protobuf-813fda9d6cf24c4f/out/version.rs:7:1
   |
7  | pub const VERSION_3_6_0: () = ();
   | --------------------------- similarly named constant `VERSION_3_6_0` defined here

It looks like this is caused by the use of a specific version on this line: https://github.com/crypto-crawler/crypto-msg-parser/blob/main/crypto-message/src/proto/message.rs#L26

Is there any way something can be done to avoid this error?

[drownbes]

@mightybyte you can just specify exact version of protobuf in your cargo.toml as a workaround. Like this:
protobuf = { version = "=3.5.0" }

[mightybyte]

That does seem to resolve the immediate build issue, thanks! However, the existence of this constant in the code seems like it will require either the above version override or a code change any time a new version of protobuf is desired. In the relatively short amount of time I've been playing with this library this has already come up for me multiple times, so maybe it could still be worthwhile to find some way to avoid having the code reference a specific version? I'll defer to others on whether to leave this ticket open though. I can see the argument for either side.