How to import bash aliases into fish - bash

Question

I am missing my bash aliases in fish, and don't want to manually convert all of them to fish functions.
How to get them all from bash to fish?
Bonus points if:
the solution supports an iterative process, as in: i can easily change the aliases in bash, and re-convert/re-import them into fish
the solution also imports bash functions

Answer 1

Convert bash aliases to bash scripts
I decided to do this instead of approach below, and putting the scripts into ~/bin/, which is in my PATH. This allows me to use them from whatever shell i am currently executing, and it prevents potential problems with quoting.
use like so:
# converts all bash aliases to script files
convert_bash_aliases_to_scripts
# removes all scripts previously converted by this script
convert_bash_aliases_to_scripts clean
bash conversion script:
#!/bin/bash
# Convert bash aliases to bash scripts.
#
# Copyright 2018 <hoijui.quaero#gmail.com>, licensed under the GPL-3.0+
#
# Usage:
# convert_bash_aliases_to_scripts # converts all bash aliases to script files
# convert_bash_aliases_to_scripts clean # removes all scripts previously converted by this script
COLOR_RED=$'\e[0;31m'
COLOR_ORANGE=$'\e[0;33m'
COLOR_BLUE=$'\e[0;34m'
COLOR_BLUE_LIGHT=$'\e[1;34m'
COLOR_GREEN=$'\e[0;32m'
COLOR_BROWN=$'\e[0;33m'
COLOR_YELLOW=$'\e[1;33m'
COLOR_WHITE=$'\e[1;37m'
COLOR_CYAN=$'\e[0;36m'
COLOR_PURPLE=$'\e[0;35m'
COLOR_GRAY=$'\e[1;30m'
COLOR_GRAY_LIGHT=$'\e[0;37m'
COLOR_NONE=$'\e[m' # No Color
OUTPUT_DIR=~/bin/converted/aliases
LINKS_DIR=~/bin
README_FILE_NAME="README.md"
README_FILE="$OUTPUT_DIR/$README_FILE_NAME"
if [ "$1" = "clean" ]
then
for script_file in $(find "$LINKS_DIR" -maxdepth 1 -type l)
do
conv_script_file="$OUTPUT_DIR/$(basename $script_file)"
if [ -e $conv_script_file ] && [ "$(readlink --canonicalize $script_file)" = "$(realpath $conv_script_file)" ]
then
script_name=$(basename $script_file)
echo "removing converted bash alias-script: $script_name"
rm $conv_script_file \
&& rm $script_file
fi
done
rm $README_FILE 2> /dev/null
rmdir $OUTPUT_DIR 2> /dev/null
exit 0
fi
SOURCE_FILES="${HOME}/.bashrc ${HOME}/.bash_aliases"
mkdir -p $OUTPUT_DIR
echo -e "# Bash alias conversion scripts\n\nsee $0\n\nWARNING: Do NOT manually edit files in this directory. instead, copy them to $LINKS_DIR (replacing the symbolic link that already exists there), and edit that new file.\nIf you edit the files in this dir, it will be replaced on the next (re)conversion from aliases." \
> $README_FILE
AUTO_IMPORT_WARNING="# WARNING Do NOT edit this file by hand, as it was auto-generated from a bash alias, and may be overwritten in the future. please read ${README_FILE}"
function _is_link_to {
local file_link=$1
local file_target=$2
test -e $file_target \
&& test "$(readlink --canonicalize $file_link)" = "$(realpath $file_target)"
return $?
}
for source_file in $SOURCE_FILES
do
IFS=$'\n'
for a in $(cat $source_file | grep "^alias")
do
a_name="$(echo "$a" | sed -e 's/alias \([^=]*\)=.*/\1/')"
a_command="$(echo "$a" | sed -e 's/alias \([^=]*\)=//' -e 's/[ \t]*#.*$//')"
if echo "${a_command:0:1}" | grep -q -e "[\'\"]"
then
# unquote
a_command_start=1
let a_command_end="${#a_command} - 2"
else
# leave as is
a_command_start=0
let a_command_end="${#a_command}"
fi
script_file="$LINKS_DIR/$a_name"
conv_script_file="$OUTPUT_DIR/$a_name"
# Check whether the script already exists.
# If so, we skip importing it, unless it is just a link to a previously imported script.
log_action="none"
log_action_color="${COLOR_NONE}"
log_content=""
if [ -e $script_file ] && ! $(_is_link_to $script_file $conv_script_file)
then
log_action="skipped (exists)"
log_action_color="${COLOR_ORANGE}"
log_content=""
else
if [ -e $script_file ]
then
log_action="reimporting"
log_action_color="${COLOR_BLUE}"
else
log_action="importing"
log_action_color="${COLOR_GREN}"
fi
# write the script file to a temporary location
conv_script_file_tmp="${conv_script_file}_BAK"
echo "#!/bin/bash" > $conv_script_file_tmp
echo -e "$AUTO_IMPORT_WARNING" >> $conv_script_file_tmp
echo -e "#\n# Imported bash alias '$a_name' from file '$source_file'" >> $conv_script_file_tmp
cat >> "${conv_script_file_tmp}" <<EOF
${a_command:${a_command_start}:${a_command_end}} \${#}
EOF
if diff -N ${conv_script_file_tmp} ${conv_script_file} > /dev/null
then
log_content="no change"
log_content_color="${COLOR_NONE}"
else
log_content="changed"
log_content_color="${COLOR_GREEN}"
fi
log_content=$(printf "%s %10s -> %s${COLOR_NONE}" "${log_content_color}" "${log_content}" "$a_command")
mv "${conv_script_file_tmp}" "${conv_script_file}"
# make the script executable
chmod +x $conv_script_file
# remove the link if it already exists (in case of reimport)
rm $script_file 2> /dev/null
# .. and re-create it as local symbolic link
# to the function in the imports dir
ln --symbolic --relative $conv_script_file $script_file
fi
printf "%s%20s: %-25s${COLOR_NONE}%s\n" "${log_action_color}" "${log_action}" "$a_name" "${log_content}"
done
done
Deprecated: Creating fish wrappers that execute bash code
Below is a script that creates fish script wrappers for the local bash aliases: For each bash alias, it takes the contents, and creates a fish alias/script that executes the code in bash sub-shell.
It is not optimal, but is sufficient for most of my aliases.
WARNING It might happen that the imported function acts differently then in bash. You may loose data or accidentally DDOS your coworkers when using them.
use like so:
# imports (or reimports) all bash aliases into fish functions, permanently
import_bash_aliases
# removes all fish functions previously imported by this script
import_bash_aliases clean
save this in ~/.config/fish/functions/import_bash_aliases.fish:
#!/usr/bin/fish
# Fish function to import bash aliases
#
# Copyright 2018 <hoijui.quaero#gmail.com>, licensed under the GPL-3.0+
#
# This script is based on a script from Malte Biermann,
# see: https://glot.io/snippets/efh1c4aec0
#
# WARNING: There is no guarantee that the imported aliases work the same way
# as they do in bash, so be cautious!
#
# Usage:
# import_bash_aliases # imports (or reimports) all bash aliases into fish functions, permanently
# import_bash_aliases clean # removes all fish functions previously imported by this script from bash aliases
function import_bash_aliases --description 'Converts bash aliases to .fish functions.\nThis might be called repeatedly, and will not override functions that are already defined in fish, except they are merely an older import from this script.'
set -l FISH_FUNCTIONS_DIR ~/.config/fish/functions
set -l BASH_IMPORTS_DIR_NAME bash-imports
set -l BASH_IMPORTS_DIR $FISH_FUNCTIONS_DIR/$BASH_IMPORTS_DIR_NAME
set -l README_FILE $BASH_IMPORTS_DIR/README.md
if test "$argv[1]" = "clean"
for fun_file in (find $FISH_FUNCTIONS_DIR -maxdepth 1 -name '*.fish')
set -l imp_fun_file $BASH_IMPORTS_DIR/(basename $fun_file)
if test -e $imp_fun_file ; and test (readlink --canonicalize $fun_file) = (realpath $imp_fun_file)
set -l fun_name (basename $fun_file '.fish')
echo "removing imported bash alias/function $fun_name"
rm $imp_fun_file
and rm $fun_file
and functions --erase $fun_name
end
end
rm $README_FILE ^ /dev/null
rmdir $BASH_IMPORTS_DIR ^ /dev/null
return 0
end
set -l SOURCE_FILES ~/.bashrc ~/.bash_aliases
mkdir -p $BASH_IMPORTS_DIR
echo -e "# Bash alias imports\n\nsee `$argv[0]`\n\nWARNING: Do NOT manually edit files in this directory. instead, copy them to $FISH_FUNCTIONS_DIR (replacing the symbolic link that already exists there), and edit that new file.\nIf you edit the files in this dir, it will be replaced on the next (re)import from bash aliases." \
> $README_FILE
set -l UNUSED_STUB_MSG "The bash alias corresponding to this function was NOT imported, because a corresponding function already exists at %s\n"
set -l AUTO_IMPORT_WARNING "# WARNING Do NOT edit this file by hand, as it was auto-generated from a bash alias, and may be overwritten in the future. please read {$README_FILE}"
function _fish_func_exists
set -l fun_name $argv[1]
# This also detects in-memory functions
functions --query $fun_name
# This also detects script files in the functions dir
# that do not contain a function wiht the same name
or test -e "$FISH_FUNCTIONS_DIR/$fun_name.fish"
return $status
end
function _is_link_to
set -l file_link $argv[1]
set -l file_target $argv[2]
test -e $file_target
and test (readlink --canonicalize $file_link) = (realpath $file_target)
return $status
end
for source_file in $SOURCE_FILES
for a in (cat $source_file | grep "^alias")
set -l a_name (echo $a | sed -e 's/alias \([^=]*\)=.*/\1/')
set -l a_command (echo $a | sed -e 's/alias \([^=]*\)=//' -e 's/[ \t]*#[^\'\"]\+$//')
set -l fun_file "$FISH_FUNCTIONS_DIR/$a_name.fish"
set -l imp_fun_file "$BASH_IMPORTS_DIR/$a_name.fish"
# Check whether the function already exists.
# If so, we skip importing it, unless it is just a link to a previously imported function.
if _fish_func_exists $a_name; and not _is_link_to $fun_file $imp_fun_file
set_color red
printf "%20s: %-25s\n" "skipping (exists)" $a_name
set_color normal
#printf $UNUSED_STUB_MSG $fun_file > $imp_fun_file
else
set_color green
printf "%20s: %-25s -> %s\n" "(re-)importing" $a_name $a_command
set_color normal
# remove the link, in case of re-importing
rm $fun_file ^ /dev/null
# write the function file
echo "#!/usr/bin/fish" > $imp_fun_file
echo "\
$AUTO_IMPORT_WARNING
function $a_name -d 'bash alias "$a_name" import'
bash -c $a_command' '\$argv''
end
" \
>> $imp_fun_file
# make the script executable
chmod +x $imp_fun_file
# .. and re-create it as local symbolic link
# to the function in the imports dir
ln --symbolic --relative $imp_fun_file $fun_file
end
end
end
# (re-)load all the functions we just defined
exec fish
end