failing to source virtualenvwrapper on alpine linux (ash)

Hi, currently the virtualenvwrapper.sh script fails to be sourced on alpine linux.

This line of code

Line 106 in c0f5193

export VIRTUALENVWRAPPER_SCRIPT="${.sh.file}"

currently causes -ash: /usr/bin/virtualenvwrapper.sh: line 109: syntax error: bad substitution when using the ash shell on alpine linux.

May be the same issue as with fish shell however I've not tried it there. Just guessing from the surrounding code.
#100

${.sh.file} is ksh syntax, but ksh support was dropped in commit d736549 so that branch probably should've been taken out too.

That still won't help your shell, though, because without a default VIRTUALENVWRAPPER_SCRIPT won't get set.

Really, using $0 should probably be the default -- that will even work in Bash, under most cases, although $BASH_SOURCE is certainly better if it's available.

Although, interestingly, when sourcing a script it seems that $0 is the ONLY thing that works for Zsh, and $BASH_SOURCE is the only thing that works for Bash.

so I guess the first question is, if you save this script to a file test_arg0.sh:

echo "0: $0"
echo "BASH_SOURCE: ${BASH_SOURCE}"
echo "ZSH_ARGZERO: ${ZSH_ARGZERO}"
echo "ZSH_SCRIPT: ${ZSH_SCRIPT}"

# Feel free to add any additional variables
# your shell's documentation indicates might be useful.

Then what do you get in ash for each of these scenarios?

(At any shell prompt):
```
ash test_arg0.sh
```
(At an ash shell prompt):
```
source test_arg0.sh
```

Here's what I get

Zsh

$ zsh test_arg0.sh
0: test_arg0.sh
BASH_SOURCE: 
ZSH_ARGZERO: test_arg0.sh
ZSH_SCRIPT: test_arg0.sh

$ source test_arg0.sh
0: test_arg0.sh
BASH_SOURCE: 
ZSH_ARGZERO: zsh
ZSH_SCRIPT:

Bash

$ bash test_arg0.sh 
0: test_arg0.sh
BASH_SOURCE: test_arg0.sh
ZSH_ARGZERO: 
ZSH_SCRIPT: 

$ source test_arg0.sh 
0: bash
BASH_SOURCE: test_arg0.sh
ZSH_ARGZERO: 
ZSH_SCRIPT:

Set VIRTUALENVWRAPPER_SCRIPT portably

May be the same issue as with fish shell however I've not tried it there. Just guessing from the surrounding code.
#100

I don't think fish is ever gonna work. It dumps out with an error anytime a variable reference uses curly braces! (What are they THINKING??)

$  source test_arg0.sh
test_arg0.sh (line 2): Variables cannot be bracketed. In fish, please use "$BASH_SOURCE".
echo "BASH_SOURCE: ${BASH_SOURCE}"

I think there's an alternative implementation for fish.

I've never heard of the ash shell. If its syntax can be supported without breaking anything, I could review patches.

@DHELLMAN

@DHELLMAN See #117, though I don't know whether that's a complete solution. It at least gives ash and others like it a fighting chance, by no longer defaulting to KSH syntax for all shells that aren't Bash or Zsh.

Set VIRTUALENVWRAPPER_SCRIPT portably

I just remembered that alpine publishes docker containers, which makes it really easy to test the ash shell on a different system. So...

$ docker pull alpine:latest
$ docker run -t -i alpine:latest /bin/ash
/ # cat > test_arg0.sh
echo "0: $0"
echo "BASH_SOURCE: ${BASH_SOURCE}"
echo "ZSH_ARGZERO: ${ZSH_ARGZERO}"
echo "ZSH_SCRIPT: ${ZSH_SCRIPT}"
/ # source test_arg0.sh
0: /bin/ash
BASH_SOURCE: 
ZSH_ARGZERO: 
ZSH_SCRIPT:

Conclusion: None of the existing methods will work for Ash. $0 shows us the wrong path. So we need to look for other supported options.

Looking at the man page, I don't see any documented method of determining the path where a sourced script is located. $0 is all it supports, and that remains the path to the shell binary.

Ah, crap, that's my fault, I shouldn't have marked that PR as "fixes" this issue, since it doesn't.

...Thanks, you beat me to it.

I've posted a StackExchange question asking how this might be solved.

(Very belated update: StackExchange produced nothing other than additional confirmation that it doesn't seem to be possible.)

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failing to source virtualenvwrapper on alpine linux (ash) #105

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failing to source virtualenvwrapper on alpine linux (ash) #105

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agowa commented on Sep 2, 2024

ferdnyc commented on Mar 24, 2025

ferdnyc commented on Mar 24, 2025

Here's what I get

Zsh

Bash

ferdnyc commented on Mar 24, 2025

dhellmann commented on Mar 29, 2025

ferdnyc commented on Mar 30, 2025

ferdnyc commented on Mar 31, 2025

ferdnyc commented on Mar 31, 2025

ferdnyc commented on Mar 31, 2025

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