I am looking to get tab-completion on my command line aliases, for example, say I defined the following alias :
alias apt-inst='sudo aptitude install' Is there a way to get the completions provided by aptitude when I hit the tab key? i.e. when I write 'sudo aptitude install gnumer' and hit tab, aptitude completes this to gnumeric, or if there was uncertainty lists all the available packages starting with gnumer. If I do it using my alias, nothing - no completion.
Try complete-alias, which solves this problem exactly. (Disclaimer: I am the author of complete_alias)
After install it you can use one generic function to complete many aliases like this:
complete -F _complete_alias <myalias1> complete -F _complete_alias <myalias2> complete -F _complete_alias <myalias3> You may want to source the complete_alias file in every bash instance through .bash_profile or similar.
mkdir ~/.bash_completion.d curl https://raw.githubusercontent.com/cykerway/complete-alias/master/complete_alias \ > ~/.bash_completion.d/complete_alias source ~/.bash_completion.d/complete_alias alias container=docker\ container complete -F _complete_alias container container can now be autocompleted by the original _docker() completion handler;
$ container l<Tab> logs ls $ container s<Tab> start stats stop There is a great thread about this on the Ubuntu forums. Ole J proposes the following alias completion definition function:
function make-completion-wrapper () { local function_name="$2" local arg_count=$(($#-3)) local comp_function_name="$1" shift 2 local function=" function $function_name { ((COMP_CWORD+=$arg_count)) # Quotes here are important COMP_WORDS=( "$@" \"\${COMP_WORDS[@]:1}\" ) "$comp_function_name" return 0 }" eval "$function" echo $function_name echo "$function" } Use it to define a completion function for your alias, then specify that function as a completer for the alias:
make-completion-wrapper _apt_get _apt_get_install apt-get install complete -F _apt_get_install apt-inst I prefer to use aliases for adding always-used arguments to existing programs. For instance, with grep, I always want to skip devices and binary files, so I make an alias for grep. For adding new commands such as grepbin, I use a shell script in my ~/bin folder. If that folder is in your path, it will get autocompleted.
complete -o default -F ... instead of complete -F ... to get things like filename auto-completion working correctly when passing args (Bash 4.3.46).CommentedDec 19, 2016 at 14:39kubectl. Here is what I am trying: alias ks=kubectl\ --context=staging; make-completion-wrapper __start_kubectl _ks kubectl --context=staging; ` complete -F _ks ks; when I type ks g` it correctly completes to ks get but then when i type ks get p I don't get expected completions like 'pods`. Am I doing something wrong?kubectl get p also does not complete as expected.By googling this issue I ended up here, so I tried the approaches in the other answers. For various reasons I don't actually understand, they never behaved properly in my Ubuntu 16.04.
What in the end worked for me was way more trivial than expected. I wanted to use the same autocompletion as rsync has for mycommand. Hence, I looked up the autocompletion function, and then called complete accordingly.
# Lookup of name of autocompletion function used for rsync _completion_loader rsync; complete -p rsync # Returns: complete -o nospace -F _rsync rsync # Sourcing the rsync functions before, then using the same function for 'mycommand' . /usr/share/bash-completion/completions/rsync complete -o nospace -F _rsync mycommand Disclaimer: I'm not sure what's the downside of my approach compared to the others. I mainly wrote this as it could help people where this trivial approach might be enough.
bash: complete: XYZ: no completion specification until you actually try to complete with XYZ the first time. I think editing the user .bash_completion file is the way to go, though I'm still not sure how..._completion_loader rsync first, to make sure the completion function is loaded. It is sometimes (always?) loaded only when you try to autocomplete with the function for the first time. This answer also has another problem: it cannot autocomplete with the context of arguments provided. E.g. it cannot make an alias for pass -c autocomplete like pass -c, only like pass. These are different.complete options, you can print the completion dynamically like so: $(complete -p rsync | rev | cut -d' ' -f 2- | rev) mycommand. /usr/share/bash-completions doesn't work if the command is installed locally (e.g. ~/.local/bin or /usr/local/share). instead try __load_completion rsync (stackoverflow.com/a/61544119)Own local completions may be defined in ~/.local/share/bash-completion/completions as explained in the bash-completion FAQs
A simple approach is thus to create this directory (if not existing) and put a file named mycommand (with alias mycommand='realcommand' as the alias definition) and to just a) source the original command's completion and b) refer to the function in complete, e.g.:
$cat ~/.local/share/bash-completion/completions/mycommand source /usr/share/bash-completion/completions/realcommand complete -F _realcommand mycommand If the function is called _realcommand. Use completion on realcommand and then complete -p | grep realcommand to see how the function is actually called.
If the alias is meant to be system-wide, one may as well place the file in /usr/share/bash-completion/completions/ directly.
Limitations
Needs manually adding the entry for each alias, not automated.
Fails if the completion function refers to the command itself:
It worked nicely for e.g. alias userctl='systemctl --user', it (partly) failed for alias mylsblk=lsblk when tab-completing anything other than mylsblk -<TAB>. This is due to the function _lsblk_module referring to the command name (via $1) in the completion script and this fails as mylsblk cannot be found as command. It worked, when I replaced $1 with lsblk in the completion script of lsblk (not recommended, done for testing purposes only).
In this case, the local completion script has to be slightly adapted so that the first argument remains the command name:
source /usr/share/bash-completion/completions/lsblk _lsblk_dummy() { _lsblk_module lsblk ; } complete -F _lsblk_dummy mylsblk which might as well be seen as general approach.
docker to just the character d. The alias gets completion even on docker CLI sub-commands like d create . Just press "TAB"! My installation notes here: github.com/dgroomes/my-config/commit/…complete -p | grep kubectl was really useful.Here's the code from Shawn J. Goff's answer with some improvements:
shell-check, eg the first " of "$@" actually ended the function definition string.return 0 so that the return value of the underlying function can be passed back to the caller..
# Wraps a completion function, eg for use with an alias. # Usage: # make-completion-wrapper <actual completion function> <name of new func.> # <command name> <list supplied arguments> # eg. # alias agi='apt-get install' # make-completion-wrapper _apt_get _apt_get_install apt-get install # # defines a function called _apt_get_install (that's $2) that will # # complete the 'agi' alias. # complete -F _apt_get_install agi function make-completion-wrapper { local function_name="$2" local arg_count=$(( $#-3 )) local comp_function_name="$1" shift 2 local function="function $function_name { (( COMP_CWORD += $arg_count )) COMP_WORDS=( \"\$@\" \${COMP_WORDS[@]:1} ) \"$comp_function_name\" }" eval "$function" # echo "$function" } export -f make-completion-wrapper 
COMP_WORDS array. If we use make-completion-wrapper _apt_get _apt_get_install apt-get install as an example, after shift 2, $@ contains apt-get install. The function definition includes apt-get install (the two literal words) when assigning COMP_WORDS.CommentedJun 3, 2019 at 19:58As an extension to @Giles answer, the following convenience function auto-names the wrapper generated by make-completion-wrapper to make it possible to define completion in one line:
function complete-alias { # uses make-completion-wrapper: https://unix.stackexchange.com/a/4220/50978 # example usage # complete-alias _pass pshow pass show # complete-alias _pass pgen pass generate EXISTING_COMPLETION_FN=${1} && shift ALIAS=${1} && shift AUTOGEN_COMPLETION_FN="__autogen_completion_${ALIAS}" make-completion-wrapper ${EXISTING_COMPLETION_FN} ${AUTOGEN_COMPLETION_FN} ${*} complete -F ${AUTOGEN_COMPLETION_FN} ${ALIAS} } 2018 answer
You must add your alias to the program 'complete'. Depending the kind of autocompletion you want to achieve, you must use -c or -F.
For package autocompletion:
complete -c name_of_your_alias For command autocompletion:
complete -F name_of_your_alias To check if your alias was added correctly:
complete | grep name_of_your_alias Finally, to remove an alias from 'complete':
complete -r name_of_your_alias In your case:
complete -c apt-inst 
complete -F xxx does not work on OSX (It just shows the usage complete: usage: complete [-abcdefgjksuv] [-pr] [-o option] [-A action] [-G globpat] [-W wordlist] [-P prefix] [-S suffix] [-X filterpat] [-F function] [-C command] [name ...]) . Do you have any pointer? Thanks.CommentedFeb 28, 2019 at 22:20complete -F name_of_your_alias simply makes no sense. Moreover, it simply fails, because it requires an additional argument.I came up with the following solution; in my case I aliased k to kubectl, and wanted to have bash completion for the k alias as well:
Make sure the bash-completion package is installed (that's the correct package name on Debian/Ubuntu/RHEL; it might be different on other distributions).
Create a file /usr/share/bash-completion/completions/k with the following content:
# Load completion for the kubectl command: . /usr/share/bash-completion/completions/kubectl # Get the completion definition for kubectl (in the form of "complete ... kubectl"): __k_kubectl_comp=$(complete -p kubectl) # Transform "complete ... kubectl" into "complete ... k" by replacing the last # word, and eval the result: eval "${__k_kubectl_comp% *} k" # That's it, clean up! unset __k_kubectl_comp Now the k alias should have the same completion as the kubectl command (you might have to open a new shell first).
This will essentially retrieve the complete command for kubectl, modify it so that it applies to the k alias, and run the resulting command. For example, complete -p kubectl on my system prints:
complete -o default -F __start_kubectl kubectl The shell script above will transform this to complete -o default -F __start_kubectl k, and run that command.
Footnote: The directory to drop bash completion code snippets into is not necessarily always /usr/share/bash-completion/completions. You can get the directory that your system uses by running pkg-config --variable=completionsdir bash-completion (see also the README of the bash-completion package).
kubectl auto-completion with --kubeconfig, do you have any solution on this ? ( details: stackoverflow.com/q/78259041/2940319 )I have noticed that a few responses are concerned with autocompleting with kubectl aliases. While other answers have addressed how to have auto complete on an alias for kubectl, they will not work when you have an alias for something like kubectl describe pod. I believe this is related to how kubectl does completion and not about completion in general.
Putting the following in my .bash_profile works to get multiword kubectl aliases working for v1.27.1:
# Load kubectl completion functions # Need to run: # kubectl completion bash > ~/.kubectl-completion # To generate the .kubectl-completion file source ~/.kubectl-completion # Create the pod-show alias alias pod-show="kubectl describe pod" # Modified from the accepted answer __start_kubectl_pods() { local compl compl=${COMP_WORDS[@]:1} (( COMP_CWORD += 2 )) COMP_WORDS=( kubectl describe pod "${compl:- }" ) __start_kubectl } # Setup completion complete -o default -F __start_kubectl_pods pod-show A couple of notes:
__start_kubectl is the main function for completing kubectl commmands. This function requires a space at the end to do completion on no arguments. I believe this is why the accepted answer does not work out of the box.export BASH_COMP_DEBUG_FILE=compdebug and then trying the completion outputs debug logs to a file named compdebug. This helped with figuring this out.The accepted answer is close but fails with some completion functions (e.g. completing an alias for npm run) due to quoting issues within its call to eval.
Here's a solution that builds on Shawn Goff's and user84207's answers, with the following improvements:
eval so the code is easier to reason about (and can be checked with shellcheck).# Adapted from https://unix.stackexchange.com/a/531400/10183 # Example usage: complete-alias _pass pgen pass generate complete_alias() { local old_completion_fn="$1" && shift local alias_name="$1" && shift local new_completion_fn="_alias_completion__${alias_name}" bind_function "$new_completion_fn" alias_completion_wrapper "$old_completion_fn" "$alias_name" "$@" complete -o default -F "$new_completion_fn" "$alias_name" } # Adapted from: # - https://unix.stackexchange.com/a/4220/50978 # - https://superuser.com/a/437508/56109 alias_completion_wrapper() { local old_completion_fn="$1" && shift local alias_name="$1" && shift local alias_command=("$@") local arg_count=$(($# - 1)) ((COMP_CWORD+=$arg_count)) COMP_WORDS=( "${alias_command[@]}" "${COMP_WORDS[@]:1}" ) (( COMP_POINT -= ${#COMP_LINE} )) COMP_LINE=${COMP_LINE/#$alias_name/${alias_command[@]}} (( COMP_POINT += ${#COMP_LINE} )) $old_completion_fn } # Creates a new function with the given name (arg 1) that calls the given # source function (arg 2) with the given arguments (remaining args). bind_function() { local dest_fn src_fn bind_args printf -v dest_fn "%q" "$1" && shift printf -v src_fn "%q" "$1" && shift printf -v bind_args "%q " "$@" eval "function $dest_fn() { $src_fn $bind_args; }" } 