Aliases that resolve to command substitutions (backticks) are highlighted as errors

[lukepass]

Hello, I recently upgraded to the latest version of zsh-syntax-highlighting but the aliases are not highlighted correctly:

plugins=(git symfony2 history-substring-search wd zsh-syntax-highlighting)

How can I fix it? Thanks!

[danielshahaf]

The latest version highlights aliases according to what they resolve to. I assume that % `_symfony_console` foo bar is also highlighted in red? (I can't test that right now)

@phy1729 might know more (but I don't know when he might have time to look).

By the way, are you sure the alias is defined correctly? Should it have been defined with double quotes?

[lukepass]

Hello @danielshahaf!
Yes, the alias is also resolved in red but it does indeed work. This alias is automatically created by the Symfony native plugin for Oh My Zsh:

In case you don't use Symfony, the php bin/console is used to launch command to update the database, create controllers etc...

Thanks.

[danielshahaf]

I still would like to understand the design choices around the alias. What's a valid use-case for defining an alias with command substitutions (backticks) on the right-hand side? (I'm not familiar with symfony.) It's not idiomatic, and there are more robust, equivalent alternatives.

Regarding zsh-syntax-highlighting, perhaps we could highlight such aliases differently: false positive unknown-token (red) highlightings should be avoided.

We have begun preparations for the 0.7.0 release. Is there any reason for this to be a blocker? I assume that "command substitutions in command position are highlighted in red" isn't a regression.

[lukepass]

Unfortunately I don't know the design choices behind this choice, the alias definition of the plugin is very simple:

https://github.com/robbyrussell/oh-my-zsh/blob/master/plugins/symfony2/symfony2.plugin.zsh

# Symfony2 basic command completion

_symfony_console () {
  echo "php $(find . -maxdepth 2 -mindepth 1 -name 'console' -type f | head -n 1)"
}

_symfony2_get_command_list () {
   `_symfony_console` --no-ansi | sed "1,/Available commands/d" | awk '/^  ?[^ ]+ / { print $1 }'
}

_symfony2 () {
   compadd `_symfony2_get_command_list`
}

compdef _symfony2 '`_symfony_console`'
compdef _symfony2 'app/console'
compdef _symfony2 'bin/console'
compdef _symfony2 sf

#Alias
alias sf='`_symfony_console`'
alias sfcl='sf cache:clear'
alias sfsr='sf server:run -vvv'
alias sfcw='sf cache:warmup'
alias sfroute='sf debug:router'
alias sfcontainer='sf debug:container'
alias sfgb='sf generate:bundle'
alias sfgc='sf generate:controller'
alias sfgcom='sf generate:command'
alias sfge='sf doctrine:generate:entity'
alias sfsu='sf doctrine:schema:update'
alias sfdc='sf doctrine:database:create'
alias sfdev='sf --env=dev'
alias sfprod='sf --env=prod'

Unfortunately I don't know which version I was using before this, but the sf command was highlighted in green.

Please let me know if I can help somehow!

Thanks!

[phy1729]

The change was likely caused by cb8c736 . PR #568 wouldn't change things since the command substitution in `echo echo` foo is highlighted as unknown-token and unknown-token is propagated up to style the alias itself.

This is another case where we need to distinguish between an error and refusal to evaluate due to possible side effects.

I would encourage you to change the definition of _symfony_console to something like

_symfony_console() {
    local consoles=(console(N.) */console(N.))
    php $console[1] "$@"
}

Which can be invoked directly instead of creating a seemingly useless subshell.

[lukepass]

Hello, unfortunately the Symfony plugin is not developed by me, can I add the suggested script in my .zshrc?

[danielshahaf]

Send the plugin maintainers a bug report. Excuse brevity.

[shortspecialbus]

I have a similar issue with an alias for colored diff output. Alias is:

alias cdiff='wdiff -w "$(tput bold;tput setaf 1)" -x "$(tput sgr0)" -y "$(tput bold;tput setaf 2)" -z "$(tput sgr0)"'

I'm not sure how to do this cleanly without being how it is, exactly, but perhaps it could also be written better. Either way, zsh-syntax-highlighting started highlighting it red at some point semi-recently, likely the same cause as the original.

[danielshahaf]

It doesn't seem like the issue @phy1729 described above, but as a workaround, you can change the alias to a function:

cdiff () { wdiff -w "$(tput bold;tput setaf 1)" -x "$(tput sgr0)" -y "$(tput bold;tput setaf 2)" -z "$(tput sgr0)" "$@" }

(Aside: Thanks for sharing that; I'll add this to my zshrc. I usually use icdiff and git diff --word-diff=color.)