hledger/shell-completion/README.md

Shell completion for CLI

This code generates shell completion scripts for hledger's command line interface. Shell completion is usually triggered by pressing the tab key once or twice after typing the command hledger . (The exact behavior may differ in shells other than Bash.)

Currently, only Bash is supported but Zsh or Fish can be added.

The completions can handle hledger's CLI:

• commands and generic options
• command-specific options
• filenames for options that take a filename as argument
• account names from journal files (but not yet for files named by --file)
• query filter keywords like status:, tag:, or amt:

Installation for end users

Completions are currently only implemented for the Bash shell.

Please check first if the completions for hledger are already installed on your distribution. Refer to the last paragraph of this section for how to test that.

To install the completions manually, follow this steps:

• Download or copy the file shell-completion/hledger-completion.bash and save it as ~/.hledger-completion.bash.

• Add the command 'source ~/.hledger-completion.bash' this to the end of your ~/.bashrc file.

• Then, you have to start a new Bash, e.g. by typing bash on the current shell.

Example installation script:

cp hledger-completion.bash ~/.hledger-completion.bash
echo 'source ~/.hledger-completion.bash' >> ~/.bashrc

Now, try it by typing hledger (with a space after the command) and press the tab key twice. You should see a list of appropriate completions for hledger. Then you can type a part of one of the suggestions and press tab again to complete it.

Background

The Bash completion script is generated (GNU make) by parsing output of hledger, hledger -h, and hledger <cmd> -h. The script also uses hledger accounts for account name completion. I propose that the Makefile is not run at every built but rather manually when the CLI changes.

Information for developers

Generate the completion script for Bash:

# change into this folder:
cd shell-completion/
make

Hint: GNU make, GNU m4, and GNU parallel must be installed to call make. The first two usually are.

The generated completion script must be installed. The package maintainer for your distribution should be responsible for this.

For now, or to live-test the script, you can use these two commands:

ln -s hledger-completion.bash ~/.hledger-completion.bash
echo 'source ~/.hledger-completion.bash' >> ~/.bashrc

After that, you have to start a new Bash, e.g. by typing bash on the current shell.

Now, try it by typing hledger (with a space after the command) and press the tab key twice. You know how completions work – if not, see above in the Installation section.

Completion scripts for other shells (e.g. Fish or Zsh)

You're welcome to add completion scripts for other shells. It should not be too hard! All available hledger options and commands are already there (generated by the Makefile).

The generated text files with options and commands are: commands.txt, generic-options.txt, and options-*.txt where * is the subcommand.

Instructions to add support for another shell:

1. Create e.g. hledger-completion.fish.m4 as a template file.

2. Add a Make rule to transform it to hledger-completion.fish.

3. Use m4 commands to include hledger options and commands into your script template. See hledger-completion.bash.m4 as a reference.

4. Use make and then make hledger-completion.fish to create and test the completion script.

5. Finally, if everything is working, also add the generated artifact hledger-completion.fish to the repo so that people can use it directly.