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A steam locomotive from 1993 broke my yarn test

(blog.cloudflare.com)
167 points jgrahamc | 5 comments | 02 Apr 25 13:10 UTC | HN request time: 0.431s | source
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bouke ◴[02 Apr 25 14:35 UTC] No.43557162[source]▶
So the real problem is that Jest just executes to whatever `sl` resolves. The fix they intent to release doesn't address that, but it tries to recognise the train steaming through. How is this acceptable behaviour from a test runner, as it looks like a disaster to happen. What if I have `alias sl=rm -rf /`, as one typically wants to have such a command close at hand?
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1. tlb ◴[02 Apr 25 14:51 UTC] No.43557349[source]▶
Exec doesn't know about shell aliases. Only what's in the $PATH.

I liked the shell in MPW (Mac Programmer's Workshop, pre-NeXT) where common commands had both long names and short ones. You'd type the short ones at the prompt, but use the long, unambiguous ones in scripts.

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2. Kwpolska ◴[02 Apr 25 15:09 UTC] No.43557546[source]▶
PowerShell has long commands and short aliases, but the aliases can still shadow executables, e.g. the `sc` alias for `Set-Content` shadows `sc.exe` for configuring services. And you only notice when you see no output and weird text files in the current working directory.
3. szszrk ◴[02 Apr 25 16:06 UTC] No.43558216[source]▶
Networking crowd probably think it's obvious. Because of things like Cisco cli, or even Mikrotik. Or "ip" cli as well, I guess.

I never bothered to check what's the origin of that pattern.

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4. hnlmorg ◴[02 Apr 25 18:51 UTC] No.43560094[source]▶
Ive taken entire web farms offline due to an unexpected expansion of a command on a Cisco load balancer.

The command in question was:

    administer-all-port-shutdown
(Or something to that effect —it’s been many years now)

And so I went to log in via serial port (like I said, *many years ago so this device didn’t have SSH), didn’t get the prompt I was expecting. So typed the user name again:

    admin
And shortly afterwards all of our alarms started going off.

The worst part of the story is that this happened twice before I realised what I’d done!

I still maintain that the full command is a stupid name if it means a phrase as common as “admin” can turn your load balancer off. But I also learned a few valuable lessons about being more careful when running commands on Cisco gear.

5. skykooler ◴[02 Apr 25 19:11 UTC] No.43560373[source]▶
Theoretically you could do this in Linux by calling /usr/bin/sl or whatever - but since various distros put binaries in different places, that would probably cause more problems than it could solve.