zsh-syntax-highlighting/highlighters/main
Nikola Knezevic e8517244f7 main: Allow for "]" in shell aliases
PR #776 fixed an issue with complex aliases and expansion. However, this change
also introduced a problem with aliases which contain `]` (for example, commonly
seen on macOS: `alias ]=open`), due to using an associative array `seen_alias`,
indexed by the alias name. Due to `"$seen_alias[$arg]"`, it would fail when
`$arg` is expanded to anything containing `]`'. Thus, typing `] /` would result
in:

```
> ] /
(anon):unset:3: seen_alias[]]: invalid parameter name
```

This change fixes the issue by ensuring we properly access keys in the
associative array `seen_alias`.

Older versions of zsh have issues with map keys having special
characters, especially lacking ways to remove such keys. The
issue is described in detail in
https://unix.stackexchange.com/questions/626393/in-zsh-how-do-i-unset-an-arbitrary-associative-array-element.

This fix uses proposal from
[zsh-workers/43269](https://www.zsh.org/mla/workers/2018/msg01073.html),
discovered by Stephane Chazelas, that boils down to avoid removing keys
from the map, and reconstruct the map anew with some keys omitted.

Co-authored-by: @phy1729
2021-03-04 20:29:43 -06:00
..
test-data main: Allow for "]" in shell aliases 2021-03-04 20:29:43 -06:00
main-highlighter.zsh main: Allow for "]" in shell aliases 2021-03-04 20:29:43 -06:00
README.md

zsh-syntax-highlighting / highlighters / main

This is the main highlighter, that highlights:

  • Commands
  • Options
  • Arguments
  • Paths
  • Strings

This highlighter is active by default.

How to tweak it

This highlighter defines the following styles:

  • unknown-token - unknown tokens / errors
  • reserved-word - shell reserved words (if, for)
  • alias - aliases
  • suffix-alias - suffix aliases (requires zsh 5.1.1 or newer)
  • global-alias - global aliases
  • builtin - shell builtin commands (shift, pwd, zstyle)
  • function - function names
  • command - command names
  • precommand - precommand modifiers (e.g., noglob, builtin)
  • commandseparator - command separation tokens (;, &&)
  • hashed-command - hashed commands
  • autodirectory - a directory name in command position when the AUTO_CD option is set
  • path - existing filenames
  • path_pathseparator - path separators in filenames (/); if unset, path is used (default)
  • path_prefix - prefixes of existing filenames
  • path_prefix_pathseparator - path separators in prefixes of existing filenames (/); if unset, path_prefix is used (default)
  • globbing - globbing expressions (*.txt)
  • history-expansion - history expansion expressions (!foo and ^foo^bar)
  • command-substitution - command substitutions ($(echo foo))
  • command-substitution-unquoted - an unquoted command substitution ($(echo foo))
  • command-substitution-quoted - a quoted command substitution ("$(echo foo)")
  • command-substitution-delimiter - command substitution delimiters ($( and ))
  • command-substitution-delimiter-unquoted - an unquoted command substitution delimiters ($( and ))
  • command-substitution-delimiter-quoted - a quoted command substitution delimiters ("$( and )")
  • process-substitution - process substitutions (<(echo foo))
  • process-substitution-delimiter - process substitution delimiters (<( and ))
  • arithmetic-expansion - arithmetic expansion $(( 42 )))
  • single-hyphen-option - single-hyphen options (-o)
  • double-hyphen-option - double-hyphen options (--option)
  • back-quoted-argument - backtick command substitution (`foo`)
  • back-quoted-argument-unclosed - unclosed backtick command substitution (`foo)
  • back-quoted-argument-delimiter - backtick command substitution delimiters (`)
  • single-quoted-argument - single-quoted arguments ('foo')
  • single-quoted-argument-unclosed - unclosed single-quoted arguments ('foo)
  • double-quoted-argument - double-quoted arguments ("foo")
  • double-quoted-argument-unclosed - unclosed double-quoted arguments ("foo)
  • dollar-quoted-argument - dollar-quoted arguments ($'foo')
  • dollar-quoted-argument-unclosed - unclosed dollar-quoted arguments ($'foo)
  • rc-quote - two single quotes inside single quotes when the RC_QUOTES option is set ('foo''bar')
  • dollar-double-quoted-argument - parameter expansion inside double quotes ($foo inside "")
  • back-double-quoted-argument - backslash escape sequences inside double-quoted arguments (\" in "foo\"bar")
  • back-dollar-quoted-argument - backslash escape sequences inside dollar-quoted arguments (\x in $'\x48')
  • assign - parameter assignments (x=foo and x=( ))
  • redirection - redirection operators (<, >, etc)
  • comment - comments, when setopt INTERACTIVE_COMMENTS is in effect (echo # foo)
  • comment - elided parameters in command position ($x ls when $x is unset or empty)
  • named-fd - named file descriptor (the fd in echo foo {fd}>&2)
  • numeric-fd - numeric file descriptor (the 2 in echo foo {fd}>&2)
  • arg0 - a command word other than one of those enumerated above (other than a command, precommand, alias, function, or shell builtin command).
  • default - everything else

To override one of those styles, change its entry in ZSH_HIGHLIGHT_STYLES, for example in ~/.zshrc:

# Declare the variable
typeset -A ZSH_HIGHLIGHT_STYLES

# To differentiate aliases from other command types
ZSH_HIGHLIGHT_STYLES[alias]='fg=magenta,bold'

# To have paths colored instead of underlined
ZSH_HIGHLIGHT_STYLES[path]='fg=cyan'

# To disable highlighting of globbing expressions
ZSH_HIGHLIGHT_STYLES[globbing]='none'

The syntax for values is the same as the syntax of "types of highlighting" of the zsh builtin $zle_highlight array, which is documented in the zshzle(1) manual page.

Parameters

To avoid partial path lookups on a path, add the path to the ZSH_HIGHLIGHT_DIRS_BLACKLIST array.

ZSH_HIGHLIGHT_DIRS_BLACKLIST+=(/mnt/slow_share)

Useless trivia

Forward compatibility.

zsh-syntax-highlighting attempts to be forward-compatible with zsh. Specifically, we attempt to facilitate highlighting command word types that had not yet been invented when this version of zsh-syntax-highlighting was released.

A command word is something like a function name, external command name, et cetera. (See Simple Commands & Pipelines in zshmisc(1) for a formal definition.)

If a new kind of command word is ever added to zsh — something conceptually different than "function" and "alias" and "external command" — then command words of that (new) kind will be highlighted by the style arg0_$kind, where $kind is the output of type -w on the new kind of command word. If that style is not defined, then the style arg0 will be used instead.