Missing cargo install --upgrade

[mqudsi]

The current procedure for updating a binary installed via cargo isn't ergonomic and is prone to human error, as there is no one-stop process for installing an updated version of a package if it exists, else leaving the current version undisturbed.

The default behavior of cargo install foo when foo is already installed is to fail to install with an error message that contains enough information to determine whether or not the output is out of date:

~> cargo install racer
    Updating crates.io index
  Installing racer v2.1.16
error: binary `racer` already exists in destination as part of `racer v2.1.16`
Add --force to overwrite

So the current process for possibly upgrading a package requires

1. cargo install foo
2. Observe the output and compare the information about the currently installed version of foo vs the version of foo that was found in the index.
3. If an upgrade is available, run cargo install foo again, but this time with the --force flag.

(The alternative is to use --force from the beginning, forcing a lengthy recompile process and wasting far more time than the above.)

[ehuss]

Thanks for the report! This is a duplicate of #2082, so closing in favor of that. There's cargo-update which handles upgrades.