conda-completion 0.2.0

Fast shell tab completion for conda and all its plugins

conda-completion

Fast shell tab completion for conda and all its plugins.

A hybrid Python/Rust conda plugin that introspects conda's argparse tree (including all plugin subcommands) and provides instant TAB completions via a tiny Rust binary.

Features

• Completes all conda commands, flags, and plugin subcommands
• Package name completion from repodata (conda install nump<TAB>)
• Version completion (conda install numpy=<TAB> lists available versions)
• Fuzzy matching for typos (numpie or nupmy suggest numpy)
• Contextual completions: environment names, task names, channels from project files (conda.toml, pixi.toml, pyproject.toml, environment.yml, anaconda-project.yml, conda-project.yml, lockfiles)
• Descriptions shown alongside candidates (zsh, fish, PowerShell)
• Fast response time (stat-cached context, no Python on the hot path)
• Shell support: bash, zsh, PowerShell (fully tested), fish (community-tested)
• Auto-regenerates the completion manifest when plugins are installed or removed

Status

This project is in early development and available from conda-forge.

Quick start (development)

# Clone and set up
git clone https://github.com/conda-incubator/conda-completion
cd conda-completion
pixi install
pixi run build

# Generate the completion manifest
conda completion generate

# Install the shell hook (auto-detects your shell)
conda completion install

# Or target a specific shell
conda completion install bash

# Or use eval directly in your RC file
eval "$(conda completion init bash)"

How it works

conda-completion splits the work into two phases:

Phase 1: Generation (Python, runs once). conda completion generate calls conda's generate_parser(), which loads all registered plugin subcommands. The argparse tree is walked recursively to extract commands, flags, positional arguments, help text, and package names from repodata. The output is a completion.msgpack manifest plus versions.index and versions.store package-version files in the platform cache directory.

Phase 2: Completion (Rust, runs on every TAB). When you press TAB, your shell calls _conda_completer, a small Rust binary (~1 MB). It reads the msgpack manifest for static command/flag/package completions, then walks project files in your working directory for dynamic completions (environment names, task names, channels). No Python runs on the hot path. Package names are matched using a three-tier strategy (prefix, substring, then fuzzy similarity) so typos like numpie still find numpy.

A stat-based file cache tracks (mtime, size) for every source file. If nothing changed since the last TAB press, the binary skips all parsing and serves cached results directly.

What files are read

Project files (walks upward from cwd, first match wins):

File	What it provides
conda.toml / pixi.toml / pyproject.toml	Environment names, task names, feature names, channels
anaconda-project.yml	Environment names, command names
conda-project.yml	Environment names, command names
environment.yml	Environment name, channels
conda.lock / pixi.lock	Locked environment names and channels
conda-lock.yml	Channel names

Global state (always read):

File	What it provides
~/.conda/environments.txt	All registered environment names
~/.condarc	Configured channel names
~/.conda/global/global.toml	Globally installed tool names

CLI commands

Command	Description
conda completion generate	Introspect conda's parser, write completion.msgpack
conda completion refresh	Force refresh package names and versions from repodata
conda completion install [shell]	Generate + install shell RC hook (auto-detects shell)
conda completion uninstall [shell]	Remove the RC hook
conda completion init <shell>	Print the shell script to stdout
conda completion status	Show cache, manifest, package-version, and binary diagnostics

install and uninstall support --dry-run to preview changes and --yes to skip confirmation.

generate and install support --no-repodata to skip package metadata. Use conda completion refresh to force a repodata refresh.

Development

pixi install
pixi run build       # build Rust binary (release)
pixi run build-debug # build Rust binary (debug)
pixi run test        # run Python + Rust integration tests
pixi run check       # lint + format + typecheck + clippy

License

BSD-3-Clause