Using bash completion with ctags and Vim

Tip 1560 Printable Monobook Previous Next

created 2008 · complexity basic · author Seanhodges · version 7.0

Add the following to your ~/.bash_completion file (create it if it does not exist):

_vim_ctags() {
    local cur prev

    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-1]}"

    case "${prev}" in
        -t)
            # Avoid the complaint message when no tags file exists
            if [ ! -r ./tags ]
            then
                return
            fi

            # Escape slashes to avoid confusing awk
            cur=${cur////\\/}

            COMPREPLY=( $(compgen -W "`awk -v ORS=" "  "/^${cur}/ { print \\$1 }" tags`" ) )
            ;;
        *)
            # Perform usual completion mode
            ;;
    esac
}

# Files matching this pattern are excluded
excludelist='*.@(o|O|so|SO|so.!(conf)|SO.!(CONF)|a|A|rpm|RPM|deb|DEB|gif|GIF|jp?(e)g|JP?(E)G|mp3|MP3|mp?(e)g|MP?(E)G|avi|AVI|asf|ASF|ogg|OGG|class|CLASS)'

complete -F _vim_ctags -f -X "${excludelist}" vi vim gvim rvim view rview rgvim rgview gview

Once you restart your bash session (or create a new one) you can type:

~$ vim -t MyC<tab key>

and it will auto-complete the tag the same way it does for files and directories:

MyClass MyClassFactory
~$ vim -t MyC

I find this really useful when I'm jumping into a quick bug fix.

Comments

I've added a similar tip for ZSH.

I was very excited to see this, but I was very annoyed that it expected a tags file in the current directory. I keep a tags file at the root of each project, and vim -t is smart enough to find the correct tags file, so I wanted bash completion to be just as smart.

So, I modified the file a bit. It will now look for a tags file in the current directory, and then keep looking in parent directories until it finds one. (note: changed `pwd` to $PWD)

_vim_ctags() {
  local cur prev

  COMPREPLY=()
  cur="${COMP_WORDS[COMP_CWORD]}"
  prev="${COMP_WORDS[COMP_CWORD-1]}"

  case "${prev}" in
    -t)
      while [ "${PWD}" != "/" ]; do
        if [ -r ./tags ]; then
          # Escape slashes to avoid confusing awk
          cur=${cur////\\/}

          COMPREPLY=( $(compgen -W "`awk -v ORS=" "  "/^${cur}/ { print \\$1 }" tags`" ) )
          return
        fi

        cd ..
      done

      return
      ;;
    *)
      # Perform usual completion mode
      ;;
  esac
}

# Files matching this pattern are excluded
excludelist='*.@(o|O|so|SO|so.!(conf)|SO.!(CONF)|a|A|rpm|RPM|deb|DEB|gif|GIF|jp?(e)g|JP?(E)G|mp3|MP3|mp?(e)g|MP?(E)G|avi|AVI|asf|ASF|ogg|OGG|class|CLASS)'

complete -F _vim_ctags -f -X "${excludelist}" vi vim gvim rvim view rview rgvim rgview gview

Thanks for posting this.

Here is how I modified the completion function with tags-file search for my own .bashrc. I basically rewrote most of it, partly just for stylistic preference, but also to make some improvements:

the upward directory search doesn't change the current directory, which is typically not a good idea in a shell function
it uses grep instead of awk. grep is most likely faster, and the invocation is simpler

_vim_ctags() {
	local cur prev

	cur=${COMP_WORDS[COMP_CWORD]}
	prev=${COMP_WORDS[COMP_CWORD-1]}

	[[ $prev = -t ]] || return

	local tagsdir=$PWD
	while [[ "$tagsdir" && ! -f "$tagsdir/tags" ]]; do
		tagsdir=${tagsdir%/*}
	done
	[[ -f "$tagsdir/tags" ]] || return

	COMPREPLY=( $(grep -o "^$cur[^	]*" "$tagsdir/tags" ) )
}

I haven't done extensive testing on it, but it works for me so far.

Note that there is an invisible tab character inside the grep pattern. --February 22, 2013

This completion function has been really helpful, but I found it to be frustratingly slow on a project with several hundred files. The linear search using grep took several seconds per search. The only tool I was able to find that performs binary searches of tags files was Vim itself, so I modified the _vim() functions above as follows. Tag completion is now incredibly fast.

_vim_search() {
    ex -N -u NONE -c 'let &tags="'$2'"' -c 'echo "\\n"' -c 'for tag in taglist("^".escape("'$1'","."))|echo tag["name"]|endfor' -cq |
    tr -s '\r' '\n' |
    sed -n '/^[a-zA-Z_]/p'
}

_vim() {
    local cur prev

    COMPREPLY=()
    cur=${COMP_WORDS[COMP_CWORD]}
    prev=${COMP_WORDS[COMP_CWORD-1]}

    case "${prev}" in
        -t)
            local tagsdir=$PWD
            while [[ "$tagsdir" && ! -f "$tagsdir/tags" ]]; do
                tagsdir=${tagsdir%/*}
            done
            [[ -f "$tagsdir/tags" ]] || return

            COMPREPLY=( $(_vim_search "$cur" "$tagsdir/tags" ) )
            return
            ;;
        *)
            # Perform usual completion mode
            ;;
    esac
}

The _vim_search() function is a bit of a hack. The stdout of ex included a number of escape sequences that I couldn't get rid of by any value of $TERM that I tried and the lines were terminated by carriage returns rather than newlines. I fixed both problems by using tr to convert all carriage returns to newlines and by using sed to get rid of anything not a tag name, which I decided would be anything not beginning with an alphabetic character or an underscore.

Using bash completion with ctags and Vim

Comments

Fan Feed