fish-shell/init/fish_function.fish

#
# This file defines various functions for fish
#


function _contains_help -d "Helper function for contains"
	echo "SYNOPSIS"
	echo \tcontains \[OPTION] KEY [VALUES...]
	echo
	echo DESCRIPTION
	echo \t-h, --help
	echo \t\tdisplay help and exit
	echo \tTest if the set VALUES contains the string KEY.
	echo \tReturn 0 if yes, 1 otherwise.
end

function contains -d "Test if a key is contained in a set of values"
	while count $argv >/dev/null
		switch $argv[1]
			case '-h' '--h' '--he' '--hel' '--help'
				_contains_help
				return

			case '--'
				# End the loop, the next argument is the key
				set -e argv[1]
				break
			
			case '-*'
				echo Unknown option $argv[$i]
                _contains_help
                return 1

			case '*'
				# End the loop, we found the key
				break				

		end
		set -e argv[1]
	end

	if count $argv >/dev/null
	else
		echo "contains: Key not specified"
		return 1
	end

	set -- key $argv[1]
	set -e argv[1]	

	#
	# Loop through values
	#

	printf "%s\n" $argv|grep -Fx -- $key >/dev/null
	return $status
end

#
# help should use 'open' to find a suitable browser, but only
# if there is a mime database _and_ DISPLAY is set, since the
# browser will most likely be graphical. Since most systems which
# have a mime databe also have the htmlview program, this is mostly a
# theoretical problem.
#

function help -d "Show help for the fish shell"

	# Declare variables to set correct scope

	set fish_browser
	set fish_browser_bg

	#
	# Find a suitable browser for viewing the help pages. This is needed
	# by the help function defined below.
	#

	set graphical_browsers htmlview x-www-browser firefox galeon mozilla konqueror epiphany opera netscape
	set text_browsers htmlview www-browser links elinks lynx w3m

	if test $BROWSER

		# User has manualy set a preferred browser, so we respect that
		set fish_browser $BROWSER

		# If browser is known to be graphical, put into background
		if contains -- $BROWSER $graphical_browsers
			set fish_browser_bg 1
		end

	else

		# Check for a text-based browser.
		for i in $text_browsers
			if which $i 2>/dev/null >/dev/null
				set fish_browser $i
				break
			end
		end

		# If we are in a graphical environment, we check if there is a
		# graphical browser to use instead.
		if test (echo $DISPLAY)
			for i in $graphical_browsers
				if which $i 2>/dev/null >/dev/null
					set fish_browser $i
					set fish_browser_bg 1
					break
				end
			end
		end
	end

	if test -z $fish_browser
		printf "help: Could not find a web browser.\n"
		printf "Please set the variable $BROWSER to a suitable browser and try again\n\n"
		return 1
	end

	set fish_help_item $argv[1]
	set fish_help_page ""

	if test $fish_help_item = .
		set fish_help_page "builtins.html\#source"
	end

	if test $fish_help_item = difference
		set fish_help_page difference.html
	end

	if test $fish_help_item = globbing
		set fish_help_page "index.html\#expand"
	end

	if contains -- $fish_help_item (builtin -n)
		set fish_help_page "builtins.html\#"$fish_help_item
	end
	
	if contains -- $fish_help_item count dirh dirs help mimedb nextd open popd prevd pushd set_color tokenize
		set fish_help_page "commands.html\#"$fish_help_item
	end
	
	set idx_subj syntax completion editor job-control todo bugs history
	set idx_subj $idx_subj killring help color prompt title expand variables
	set idx_subj $idx_subj builtin-overview changes

	if contains -- $fish_help_item $idx_subj
		set fish_help_page "index.html\#"$fish_help_item
	end

	if not test $fish_help_page
		if which $fish_help_item >/dev/null ^/dev/null
			man $fish_help_item
			return
		end
		set fish_help_page "index.html"
	end

	if test $fish_browser_bg
		eval $fish_browser file://$__fish_help_dir/$fish_help_page \&
	else
		eval $fish_browser file://$__fish_help_dir/$fish_help_page
	end

end

#
# Make ls use colors if we are on a system that supports this
#
if ls --help 1>/dev/null 2>/dev/null
	function ls -d "List contents of directory"
		command ls --color=auto --indicator-style=classify $argv
	end
end

#
# These are very common and useful
#
function ll -d "List contents of directory using long format"
	ls -lh $argv
end

function la -d "List contents of directory using long format, showing hidden files"
	ls -lha $argv
end

#
# This allows us to use 'open FILENAME' to open a given file in the default
# application for the file.
#

function open -d "Open file in default application"
	mimedb -l -- $argv
end

#
# Print the current working directory. If it is too long, it will be
# ellipsised. This function is used by the default prompt command.
#

function prompt_pwd -d "Print the current working directory, ellipsise it if it is longer than 1/4 of the terminal width"
	set wd (pwd)
	set len (echo $wd|wc -c)
	set max_width (echo $COLUMNS/4|bc)
	if test $len -gt $max_width
		#Write ellipsis character if known to be using UTF
		#else use $
		set -l ellipsis "$" #default
		if count $LANG >/dev/null
			if test (expr match $LANG ".*UTF") -gt 0
				set ellipsis \u2026
			end
		end
		printf %s%s $ellipsis (echo $wd|cut -c (echo $len-$max_width-1|bc)-)
	else
		echo $wd
	end
end

#
# Make pwd print out the home directory as a tilde.
#

function pwd -d "Print working directory"
	set out (command pwd $argv)
	if echo $out| grep \^$HOME >/dev/null
		printf \~
		echo $out |cut -b (echo $HOME|wc -c)-
	else
		printf "%s\n" $out
	end
end

#
# This is a neat function, stolen from zsh. It allows you to edit the
# value of a variable interactively.
#

function vared -d "Edit variable value"
	if test (count $argv) = 1
		switch $argv

			case '-h' '--h' '--he' '--hel' '--help'
				printf "Synopsis\n\t%svared%s VARIABLE\n\n" (set_color $FISH_COLOR_COMMAND) (set_color $FISH_COLOR_NORMAL)
				printf "\tInteractively edit the value of an environment variable\n\n"

			case '-*'
				printf "vared: Unknown option %s\n" $argv

			case '*'
				if test (count $$argv ) -lt 2
					set init ''
					if test $$argv
						set init -- $$argv
					end
					set prompt 'set_color green; echo '$argv'; set_color normal; echo "> "'
					read -p $prompt -c $init tmp

					# If variable already exists, do not add any
                    # switches, so we don't change export rules. But
                    # if it does not exist, we make the variable
                    # global, so that it will not die when this
                    # function dies

					if test $$argv
						set -- $argv $tmp
					else
						set -g -- $argv $tmp
					end

				else

					printf "vared: %s is an array variable. Use " $argv
					set_color $FISH_COLOR_COMMAND
					printf vared
					set_color $FISH_COLOR_NORMAL
					printf " %s[n] to edit the n:th element of %s\n" $argv $argv

				end
		end
	else
		printf "vared: Expected exactly one argument, got %s.\n\nSynopsis:\n\t" (count $argv)
		set_color $FISH_COLOR_COMMAND
		printf vared
		set_color $FISH_COLOR_NORMAL
		printf " VARIABLE\n"
	end
end

#
# This function is bound to Alt-L, it is used to list the contents of
# the directory under the cursor
#

function __fish_list_current_token -d "List contents of token under the cursor if it is a directory, otherwise list the contents of the current directory"
	set val (eval echo (commandline -t))
	if test -d $val
		ls $val
	else
		set dir (dirname $val)
		if test $dir != . -a -d $dir
			ls $dir
		else
			ls
		end
	end
end


function pushd -d "Push directory to stack"
	# Comment to avoid set completions
	set -g dirstack (command pwd) $dirstack
	cd $argv[1]
end


function popd -d "Pop dir from stack"
	if test $dirstack[1]
		cd $dirstack[1]
	else
		echo Directory stack is empty...
		return 1
	end

	set -e dirstack[1]

end


function dirs -d "Print directory stack"
	echo -n (command pwd)"  "
	for i in $dirstack
		echo -n $i"  "
	end
	echo
end


#
# The following functions add support for a directory history
#

function cd -d "Change directory"

	# Skip history in subshells
	if status --is-command-substitution
		builtin cd $argv
		return $status
	end

	# Avoid set completions
	set -- previous (command pwd)

	if test $argv[1] = - ^/dev/null
		if test $__fish_cd_direction = next ^/dev/null
			nextd
		else
			prevd
		end
		return $status
	end
				
	builtin cd $argv[1]

	if test $status = 0 -a (command pwd) != $previous
		set -g dirprev $dirprev $previous
		set -e dirnext
		set -g __fish_cd_direction prev
	end

	return $status
end


function __fish_move_last -d "Move the last element of a directory history from src to dest"
	set src $argv[1]
	set dest $argv[2]

	set size_src (count $$src)

	if test $size_src = 0
		# Cannot make this step
		echo "Hit end of history..."
		return 1
	end

	# Append current dir to the end of the destination
	set -g (echo $dest) $$dest (command pwd)

	set ssrc $$src
		
	# Change dir to the last entry in the source dir-hist
	builtin cd $ssrc[$size_src]

	# Keep all but the last from the source dir-hist 
	set -e (echo $src)[$size_src]

	# All ok, return success
	return 0
end	


function prevd -d "Move back in the directory history"
	# Parse arguments
	set show_hist 0 
	set times 1
	for i in (seq (count $argv))
		switch $argv[$i]
			case '-l'
				set show_hist 1
				continue
			case '-*'
				echo Uknown option $argv[$i]
				return 1
			case '*'
				if test $argv[$i] -ge 0 ^/dev/null
					set times $argv[$i]
				else
					echo "The number of positions to skip must be a non-negative integer"
					return 1
				end
				continue
		end
	end

	# Traverse history
	set code 1
	for i in (seq $times)
		# Try one step backward
		if __fish_move_last dirprev dirnext;
			# We consider it a success if we were able to do at least 1 step
			# (low expectations are the key to happiness ;)
			set code 0
		else
			break
		end
	end

	# Show history if needed
	if test $show_hist = 1
		dirh
	end

	# Set direction for 'cd -'
	if test $code = 0 ^/dev/null
		set -g __fish_cd_direction next
	end

	# All done
	return $code
end 


function nextd -d "Move forward in the directory history"
	# Parse arguments
	set show_hist 0 
	set times 1
	for i in (seq (count $argv))
		switch $argv[$i]
			case '-l'
				set show_hist 1
				continue
			case '-*'
				echo Uknown option $argv[$i]
				return 1
			case '*'
				if test $argv[$i] -ge 0 ^/dev/null
					set times $argv[$i]
				else
					echo "The number of positions to skip must be a non-negative integer"
					return 1
				end
				continue
		end
	end

	# Traverse history
	set code 1
	for i in (seq $times)
		# Try one step backward
		if __fish_move_last dirnext dirprev;
			# We consider it a success if we were able to do at least 1 step
			# (low expectations are the key to happiness ;)
			set code 0
		else
			break
		end
	end

	# Show history if needed
	if test $show_hist = 1
		dirh
	end

	# Set direction for 'cd -'
	if test $code = 0 ^/dev/null
		set -g __fish_cd_direction prev
	end

	# All done
	return $code
end 


function dirh -d "Print the current directory history (the back- and fwd- lists)" 
	# Avoid set comment
	set current (command pwd)
	set -- separator "  "
	set -- line_len (echo (count $dirprev) + (echo $dirprev $current $dirnext | wc -m) | bc)
	if test $line_len -gt $COLUMNS
		# Print one entry per line if history is long
		set separator "\n"
	end

	for i in $dirprev
		echo -n -e $i$separator
	end

	set_color $fish_color_history_current
	echo -n -e $current$separator
	set_color normal
	
	for i in (seq (echo (count $dirnext)) -1 1)
		echo -n -e $dirnext[$i]$separator
	end

	echo
end


function type -d "Print the type of a command"

	set status 0
	set mode normal

	for i in $argv
		switch $i
			case -t --t --ty --typ --type
				set mode type
			
			case -p --p --pa --pat --path
				set mode path
			
			case -a --a --al --all
				set mode all

			case --
				 break

			case '-*'
				 echo Unknown option $i
				 return 1
		end
	end

	switch $mode

		case normal
			for i in $argv

				switch $i
					case '-*'
						continue;
				end

				if contains -- $i (functions -n)
					echo $i is a function with definition
					functions $i
					continue
				end

				if contains -- $i (builtin -n)
					echo $i is a shell builtin
					continue
				end

				if which $i ^/dev/null >/dev/null
					echo $i is (which $i)
					continue
				end
				echo type: $i: not found
				set status 1		
			end

		case path
			for i in $argv

				switch $i
					case '-*'
						continue;
				end

				if which $i ^/dev/null >/dev/null
					echo $i is (which $i)
					continue
				end
				set status 1		
			end

		case all
			for i in $argv
				set found ""
				switch $i
					case '-*'
						continue;
				end

				if contains -- $i (functions -n)
					echo $i is a function with definition
					functions $i
					set found 1
				end

				if contains -- $i (builtin -n)
					echo $i is a shell builtin
					set found 1
				end

				if which $i ^/dev/null >/dev/null
					echo $i is (which $i)
					set found 1
				end

				if test -z $found
					echo type: $i: not found
					set status 1		
				end
			end

		 
		case type
			for i in $argv

				switch $i
					case '-*'
						continue;
				end

				if contains -- $i (functions -n)
					echo function
					continue
				end

				if contains -- $i (builtin -n)
					echo builtin
					continue
				end

				if which $i ^/dev/null >/dev/null
					echo file
					continue
				end
				set status 1		
			end
	end

	return $status
end

function prevd-or-backward-word --key-binding 
	if test -z (commandline)
		prevd
	else
		commandline -f backward-word
	end
end

function nextd-or-forward-word --key-binding 
	if test -z (commandline)
		nextd
	else
		commandline -f forward-word
	end
end

#
# This function deletes a character from the commandline if it is
# non-empty, and exits the shell otherwise. Implementing this
# functionality has been a longstanding request from various
# fish-users.
#

function delete-or-exit --key-binding -d "Exit the shell if the commandline is empty, delete a character otherwise"
	if test (commandline)
		commandline -f delete-char
	else
		exit
	end
end