Using alt def with relative paths results in crash when running binary from different directory

[dotboris]

Here's a simple example:

$ alt def node 18 ./opt/node-18.12.1/bin/node
$ alt use node 18
Will now use node 18 (./opt/node-18.12.1/bin/node) when in /home/dotboris
$ node --version
v18.12.1
$ cd code/dotboris-io
$ alt show
Versions from: /home/dotboris/code/dotboris-io/.alt.toml
node
 * 18 (./opt/node-18.12.1/bin/node)
python (using system)
   3 (/usr/bin/python3)
$ node --version
🔥 alt failed to run node version 18!
error: Os { code: 2, kind: NotFound, message: "No such file or directory" }
command: node
command version: 18
args: ["--version"]
bin: ./opt/node-18.12.1/bin/node
current dir: Ok("/home/dotboris/code/dotboris-io")
thread 'main' panicked at 'explicit panic', src/exec_cmd.rs:47:13
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

The core of the issue is that alt def takes the path its given as is and stores it. When this path is relative, it's sensitive to the current directory which doesn't work in most cases.

The simple solution here is to make the path absolute before storing it.