Rust & Amethyst - Error [E0433]: failed to resolve: could not find `__rt` in `quote` - rust

Question

I'm learning Rust from "Practical Rust Projects" by Shing Lyu. I'm now trying to build a game following the steps in Chapter 4. I'm working on Ubuntu 18.04 LTS.
After installing Rust and the Amethyst command line, I created a new project via amethyst new cat_volleyball. The next step is to run the engine using cargo run --features=vulkan
. When I do so, I get the error prompt below. Do you have suggestions on how to fix this?
error[E0433]: failed to resolve: could not find `__rt` in `quote`
--> /home/alberto/.cargo/registry/src/github.com-1ecc6299db9ec823/err-derive-0.1.6/src/lib.rs:145:63
|
145 | fn display_body(s: &synstructure::Structure) -> Option<quote::__rt::TokenStream> {
| ^^^^ could not find `__rt` in `quote`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0433`.
error: could not compile `err-derive`.
warning: build failed, waiting for other jobs to finish...

Answer 1

TL;DR Edit the Cargo.lock manually, please check the title below : How to force cargo to use yanked version of sub-dependency (for the proper steps)
Why this happens ?
This happened because in err-derive-0.1.6 is using quote-1.0.2 as dependency but in it's cargo.toml dependency declared like this:
[dependencies.quote]
version = "1.0.2"
This means cargo will use the latest minor update, so if quote-1.0.3 is out then cargo will use 1.0.3 instead 1.0.2. Please check caret-requirement. The problem in here is quote-1.0.3 breaks backward compatibility that comes from quote-1.0.2. In this case quote
How to force cargo to use specific version of sub-dependency
You can fix this issue by forcing the sub-dependency to use compatible version for your dependency.
This command will do it :
> cargo update -p quote --precise 1.0.2
How to force cargo to use yanked version of sub-dependency
Looks like quote-1.0.2 was yanked from crates.io, so command up above will not work because cargo will not be able to find the yanked version on crates.io . Since cargo update modifies the cargo.lock we can do it manually. To start clean :
Remove Cargo.lock
Run cargo update ( this will generate latest version Cargo.lock )
Edit Cargo.lock
Find the incompatible version of package in cargo.lock which is quote-1.0.3, It should look like this:
[[package]]
name = "quote"
version = "1.0.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
]
then simply change version to the compatible version in our case it is "1.0.2"
[[package]]
name = "quote"
version = "1.0.2"
After doing that do not run cargo update again, it will overwrite your changes and you'll not able to compile your project. Please remember this is a workaround for being able to continue the development, there is a reason to yank crates, do not use it in production it is best to wait dependent crates to update itself.
Note : In some cases you may get an error after editing cargo.lock:
error: Found argument 'Cargo.lock' which wasn't expected, or isn't valid in this context
#albus_c fixed this by doing :
A note for posterity: I fixed the issue removing rustc
(sudo apt remove rustc) and reinstalled as recommended on the Rust website,
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
After that everything worked fine.