Cargo: `cargo install` should accept --version (in addition to --vers?)

[shepmaster]

It's a long command line option; it shouldn't be needlessly truncated.

[alexcrichton]

Unfortunately cargo install --version already prints out Cargo's version number (name clash here)

[shepmaster]

It appears that --version is currently unknown to cargo install:

$ cargo install diesel_cli --no-default-features --features postgres --version
error: Unknown flag: '--version'

$ cargo install diesel_cli --no-default-features --features postgres --version 0.16.0
error: Unknown flag: '--version'

$ cargo install --version diesel_cli
error: Unknown flag: '--version'

$ cargo install diesel_cli --version
error: Unknown flag: '--version'

$ cargo install --version
error: Unknown flag: '--version'

[alexcrichton]

Heh, I'd consider that a bug!

[shepmaster]

Heh, I'd consider that a bug!

It's not unique:

$ cargo new --version
error: Unknown flag: '--version'

$ cargo build --version
error: Unknown flag: '--version'

$ cargo clean --version
error: Unknown flag: '--version'

$ cargo test --version
error: Unknown flag: '--version'

$ cargo search --version
error: Unknown flag: '--version'

Can we make lemonade out of this lemon and only support --version on plain cargo? Especially if no one is complaining about the "bug"...

[alexcrichton]

Hm I suppose so yeah!

[shepmaster]

A quick skim through all the built-in subcommands shows they all have the same behavior.

Cleaned-up output of all commands

cargo bench --version
error: Unknown flag: '--version'

cargo build --version
error: Unknown flag: '--version'

cargo check --version
error: Unknown flag: '--version'

cargo clean --version
error: Unknown flag: '--version'

cargo doc --version
error: Unknown flag: '--version'

cargo fetch --version
error: Unknown flag: '--version'

cargo generate-lockfile --version
error: Unknown flag: '--version'

cargo git-checkout --version
error: Unknown flag: '--version'

cargo help --version
error: no such subcommand: `--version`

cargo init --version
error: Unknown flag: '--version'

cargo install --version
error: Unknown flag: '--version'

cargo locate-project --version
error: Unknown flag: '--version'

cargo login --version
error: Unknown flag: '--version'

cargo metadata --version
error: Unknown flag: '--version'

cargo new --version
error: Unknown flag: '--version'

cargo owner --version
error: Unknown flag: '--version'

cargo package --version
error: Unknown flag: '--version'

cargo pkgid --version
error: Unknown flag: '--version'

cargo publish --version
error: Unknown flag: '--version'

cargo read-manifest --version
error: Unknown flag: '--version'

cargo run --version
error: Unknown flag: '--version'

cargo rustc --version
error: Unknown flag: '--version'

cargo rustdoc --version
error: Unknown flag: '--version'

cargo search --version
error: Unknown flag: '--version'

cargo test --version
error: Unknown flag: '--version'

cargo uninstall --version
error: Unknown flag: '--version'

cargo update --version
error: Unknown flag: '--version'

cargo verify-project --version
error: Unknown flag: '--version'

cargo version --version
error: Unknown flag: '--version'. Did you mean 'version'?

cargo yank --version
error: Unknown flag: '--version'

---

Third-party cargo subcommands do frequently support --version, but that seems like a reasonable difference.

[carols10cents]

cargo version --version
error: Unknown flag: '--version'. Did you mean 'version'?

lol

[kivikakk]

It's real easy to fix this naïvely:

diff --git a/src/bin/install.rs b/src/bin/install.rs
index c7062d40..35a09a74 100644
--- a/src/bin/install.rs
+++ b/src/bin/install.rs
@@ -23,7 +23,7 @@ pub struct Options {
     flag_locked: bool,

     arg_crate: Vec<String>,
-    flag_vers: Option<String>,
+    flag_version: Option<String>,

     flag_git: Option<String>,
     flag_branch: Option<String>,
@@ -43,7 +43,7 @@ Usage:
     cargo install [options] --list

 Specifying what crate to install:
-    --vers VERS               Specify a version to install from crates.io
+    --version VERSION         Specify a version to install from crates.io
     --git URL                 Git URL to install the specified crate from
     --branch BRANCH           Branch to use when installing from git
     --tag TAG                 Tag to use when installing from git
@@ -151,7 +151,7 @@ pub fn execute(options: Options, config: &mut Config) -> CliResult {
     };

     let krates = options.arg_crate.iter().map(|s| &s[..]).collect::<Vec<_>>();
-    let vers = options.flag_vers.as_ref().map(|s| &s[..]);
+    let vers = options.flag_version.as_ref().map(|s| &s[..]);
     let root = options.flag_root.as_ref().map(|s| &s[..]);

The problem is we probably want to support --vers as well (for at least some period of time), but ideally without showing it in the USAGE string. This seems a bit complicated with the way cargo subcommands are put together currently.

[alexcrichton]

@kivikakk that looks fine to me, but I don't think we'll want to deprecate the --vers flag any time soon, instead we can probably just accept both flags (and prefer one arbitrarily if both are passed)

[kivikakk]

@alexcrichton agreed! Showing both in the USAGE feels a bit gross, is all. I'll see how it looks in practice.