Skip to content

Enable completion for both bash and zsh #1514

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
janweinschenker wants to merge 4 commits into
base: master
Choose a base branch
from
Draft

Enable completion for both bash and zsh #1514

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
52e4042
feat: add script that enabled code completion for both bash and zsh
Jan 15, 2026
06e2b76
Delete ZSH_COMPLETION.md
janweinschenker Jan 15, 2026
a17a508
refactor: extract zsh check into separate function.
Jan 15, 2026
a3424ce
chore: merge
Jan 15, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
159 changes: 159 additions & 0 deletions BASH_ZSH_COMPLETION.adoc
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,159 @@
= Changes from Bash to Zsh Completion Script

This document outlines the changes made to adapt `mvnd-bash-completion.bash` for zsh compatibility in `mvnd-bash+zsh-completion.sh`. These changes enable the same completion script to work in both bash and zsh shells.

== Overview

The zsh version of the completion script maintains backward compatibility with bash while adding zsh-specific enhancements. The script auto-detects the shell type and applies the appropriate behavior.

== Key Changes

=== 1. Shell Detection

A new shell detection mechanism was added at the beginning of the script:

[source,shell]
----
if [ -n "$ZSH_VERSION" ]; then
__MVND_SHELL="zsh"
elif [ -n "$BASH_VERSION" ]; then
__MVND_SHELL="bash"
else
__MVND_SHELL="unknown"
fi
----

This allows the script to conditionally execute shell-specific code paths.

=== 2. Zsh Completion System Initialization

A new block initializes the zsh completion system and enables bash compatibility mode:

[source,shell]
----
if [ "$__MVND_SHELL" = "zsh" ]; then
# Enable bash compatibility
autoload -Uz compinit
compinit -u 2>/dev/null

# Load bashcompinit for bash-style completions
autoload -Uz bashcompinit
bashcompinit

# Set options for better compatibility
setopt NO_BEEP
setopt COMPLETE_IN_WORD
setopt ALWAYS_TO_END

# Define COMP_WORDBREAKS if not set (bash compatibility)
[[ -z "$COMP_WORDBREAKS" ]] && COMP_WORDBREAKS=$' \t\n"\'><=;|&(:'
fi
----

Key components:

* `compinit` - Initializes zsh's completion system
* `bashcompinit` - Enables bash-style completion functions (`complete`, `compgen`, `COMPREPLY`)
* `setopt` - Sets zsh options for improved completion behavior
* `COMP_WORDBREAKS` - Defines word break characters (bash sets this automatically)

=== 3. Function Existence Check

The `function_exists` function was modified to handle both shells:

[cols="1,1"]
|===
| Bash | Zsh

| `declare -F $1 > /dev/null`
| `typeset -f $1 > /dev/null 2>&1`
|===

Zsh uses `typeset` instead of `declare` for function introspection. The `2>&1` redirect suppresses potential error messages.

=== 4. Variable Listing for Plugin Discovery

The `common_plugins` variable discovery was updated:

[cols="1,1"]
|===
| Bash | Zsh

| `compgen -v \| grep "^plugin_goals_.*"`
| `typeset + \| grep "^plugin_goals_"`
|===

* Bash uses `compgen -v` to list all variable names
* Zsh uses `typeset +` to list variable names (the `+` modifier shows only names)

=== 5. Indirect Variable Expansion

When accessing plugin goals dynamically by variable name, different syntax is required:

[cols="1,1"]
|===
| Bash | Zsh

| `${!var_name}`
| `${(P)var_name}`
|===

* Bash uses `${!var_name}` for indirect expansion (dereference)
* Zsh uses `${(P)var_name}` - the `(P)` flag enables parameter name expansion

The updated code:

[source,shell]
----
local var_value
if [ "$__MVND_SHELL" = "zsh" ]; then
var_value="${(P)var_name}"
else
var_value="${!var_name}"
fi
COMPREPLY=( $(compgen -W "${var_value}" -S ' ' -- ${cur}) )
----

== Summary of Shell Differences

[cols="2,2,3"]
|===
| Feature | Bash | Zsh

| Function existence check
| `declare -F name`
| `typeset -f name`

| List variables
| `compgen -v`
| `typeset +`

| Indirect variable expansion
| `${!varname}`
| `${(P)varname}`

| Completion system init
| Built-in
| `autoload -Uz compinit && compinit`

| Bash compatibility
| N/A
| `autoload -Uz bashcompinit && bashcompinit`

| Word break characters
| Auto-set in `COMP_WORDBREAKS`
| Must be manually defined
|===

== Usage

The script works automatically in both shells. Simply source it in your shell configuration:

[source,shell]
----
# In ~/.bashrc or ~/.zshrc
source /path/to/mvnd-bash+zsh-completion.sh
----

Or use the provided `mvnd --completion` command to generate and source the completion script.

Loading