Handle parentheses in variables in commands

[i7an]

Variables with parentheses are not handled correctly in commands:

FOO='passwo(rd'
BAR=$(echo '$FOO')

Result:

expected: {"BAR"=>"passwo(rd",           "FOO"=>"passwo(rd"}
     got: {"BAR"=>"$(echo 'passwo(rd')", "FOO"=>"passwo(rd"}

The solution I suggest is to parse commands first and expand variables before executing commands.

Dependencies

This change will break kamal which is included in Rails by default. This is how I want to handle it:

• Get an approval for the dotenv patch but not merge it.
• Deliver backward compatible fix to kamal https://github.com/basecamp/kamal/pull/1346
• Merge this PR once the patched version of kamal is released.

[mrj]

Will this also fix #530 (improperly expanding double-quotes in command variables)? This makes Kamal only able to use JSON secrets when its double-quotes are backslashed. I see you escaped quotes and braces in your secrets example. Shouldn't neither be necessary, so the secrets can be normal JSON?

[i7an]

@mrj Unfortunately this PR does not fix the issue you reported.

[bkeepers]

@i7an thanks for reporting this and coming up with a fix. I'm good with going forward with this, let me know when you're ready.

Can you also add a test case that verifies that command => variable => command works?

FOO=$(echo bar)
BAR-$(echo $FOO)

Should equal

FOO=bar
BAR=bar

:turtle: :turtle: :turtle:

[i7an]

@bkeepers this PR is ready to be merged. Context. Kamal released a new version that includes the backward compatibility fix which this PR was waiting for.

[i7an]

@bkeepers ping

[i7an]

@bkeepers ping ping