Bash syntax errors reported when loading cargo shell completions

[jimmycuadra]

This is a re-report of rust-lang/rustup#1799, per the comment it received.

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Problem

The cargo command completion shell script produces syntax errors when loaded:

-bash: /redacted/.rustup/toolchains/stable-x86_64-apple-darwin/etc/bash_completion.d/cargo: line 82: syntax error in conditional expression: unexpected token `('
-bash: /redacted/.rustup/toolchains/stable-x86_64-apple-darwin/etc/bash_completion.d/cargo: line 82: syntax error near `@(t'
-bash: /redacted/.rustup/toolchains/stable-x86_64-apple-darwin/etc/bash_completion.d/cargo: line 82: `		if [[ "${cmd}" = @(test|bench) ]]; then'

Steps

1. Install latest rustup. I'm using rustup 1.18.0 (8603e2c56 2019-04-22).
2. Run source $(rustc --print sysroot)/etc/bash_completion.d/cargo in a shell.
3. Observe output.

Possible Solution(s)

Notes

Output of bash --version:
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin18)
Copyright (C) 2007 Free Software Foundation, Inc.

Output of rustup --version: rustup 1.18.0 (8603e2c56 2019-04-22)
Output of cargo --version: cargo 1.34.0 (6789d8a 2019-04-01)

[ArifRoktim]

The @(pattern-list) syntax was introduced in bash 4.0 4.1*. Is it feasible for you to update your version of bash?

The feature was actually introduced in bash 2.02, controlled by the extglob option, but enabled by default starting with version 4.1. So you can either upgrade bash to be version 4.1 or greater, or manually enable the extglob option in your .bashrc.

Source: http://tiswww.case.edu/php/chet/bash/NEWS

[jimmycuadra]

I'm apparently using the version that comes installed on the latest macOS. I could have sworn I used to have a more recent version installed via Homebrew...

In any case, I can fix upgrade/enable the option, but if this script will fail in the same way for everyone else on stock macOS, that doesn't seem acceptable.