# has

`has` checks presence of various command line tools on the PATH and reports their installed version.

[![Build Status](https://github.com/kdabir/has/actions/workflows/main.yml/badge.svg)](https://github.com/kdabir/has/actions/workflows/main.yml)

[![demo](demo.svg)](demo.svg)

## Quick Start 🚴

Just [install](#installing-) the `has` script, (there is no dependency apart from `bash` itself). From the command line, pass the list of commands you want to check as arguments to `has`, for example:

```console
$ has node npm java git gradle
✓ node 22.17.0
✓ npm 11.5.1
✓ java 21.0.7
✓ git 2.50.1
✓ gradle 8.14.2
```

If everything is good `has` exits with status code `0`. The exit status code reflects number of commands **not found** on your path.

```console
$ has node go javac
✓ node 22.17.0
✓ go 1.24.5
✘ javac
```

And echo the status:

```console
$ echo $?
1
```

## Use `has` in scripts

`has` can be used in shell scripts to check presence of tool in very readable way

```bash
if has node
    then echo you have what it takes 🎉
fi
```

**Pro Tip**: the `has` in above command can be replaced with the entire curl command for to ensure portability of script → `if curl -sL https://git.io/_has | bash -s node then ...`


## Installing 🚀

`has` is a single bash script that does it all. You can [download](https://raw.githubusercontent.com/kdabir/has/master/has) the script and make it available on your `$PATH`. However, to make it even simpler, just follow *one* of these methods.

### Homebrew (MacOS) 🍺

Just run the following: 

```bash
brew install kdabir/tap/has
```

### Cloning the Repo

Just execute the following command in a terminal: it clones `has` repo and installs it into your path.

```bash
git clone https://github.com/kdabir/has.git && cd has && sudo make install
```

For a non-root installation:

```bash
git clone https://github.com/kdabir/has.git
cd has
make PREFIX=$HOME/.local install
```

To update just do a `git fetch` or `make update` followed by the appropriate `make install` command.

### Downloading to a file

```bash
curl -sL https://git.io/_has > /usr/local/bin/has
```

```bash
curl -sL https://git.io/_has | sudo tee /usr/local/bin/has >/dev/null
```

These commands are safe to be called multiple times as well (to update `has`)

### asdf users

```
asdf plugin add has https://github.com/sylvainmetayer/asdf-has
asdf install has 1.4.0
```

### mise-en-place users

```bash
mise use -g has@latest
```

### Running directly off the Internet

If you are lazy, you can run `has` directly off the Internet as well:

```console
curl -sL https://git.io/_has | bash -s git node npm
✓ git 2.50.1
✓ node 22.17.0
✓ npm 11.5.1
```

**ProTip**: if that's too much typing every time, setup an alias in your `.bashrc`/`.zshrc` file:

```.bashrc
alias has="curl -sL https://git.io/_has | bash -s"
```

And use it

```console
$ has git
✓ git 2.50.1
$ type has
has is aliased to `curl -sL https://git.io/_has | bash -s'
```

## Command not understood by has?

Let's say `$ has foobar` returns `foobar not understood`, because `has` may not have whitelisted `foobar`.

In such cases, pass `HAS_ALLOW_UNSAFE=y has foobar`. This should still check for existence of `foobar` and tries to detect version as well.

> the value must exactly be `y` for it to work.

## The `.hasrc` file

`has` looks for `.hasrc` file in the directory from where `has` command is issued. This file can contain commands that `has`
will check for. List one command per line. Lines starting with `#` are treated as comments.

Following is example of `.hasrc` file:

```hs
# tools
git
curl

# interpreters
ruby
node
```

When `has` is run in directory containing this file, it produces:

```console
$ has
✓ git 2.50.1
✓ curl 8.5.0
✓ ruby 3.4.1
✓ node 22.17.0
```

Also, CLI arguments passed to `has` are additive to `.hasrc` file. For example, in the same dir, if the following command is fired,
`has` checks for both commands passed from cli args and provided in `.hasrc` file.

```bash
$ has java
✓ java 21.0.7
✓ git 2.50.1
✓ curl 8.5.0
✓ ruby 3.4.1
✓ node 22.17.0
```

**Pro Tip**: commit `.hasrc` file in root of your project. This can work as a quick check for confirming presence all command
line tools required to build and run your project.

On machines that don't even have `has` installed, your project's `.hasrc` is honored by this command:

`curl -sL https://git.io/_has | bash -s`

> take a look at [.hasrc](https://github.com/kdabir/has/blob/master/.hasrc) file for this repo.

## Supporting

here are some ways you can help:

1. Star the repo, write about it, spread the word
2. Update the documentation (including this README)
3. Adding support for more commands and features - see [CONTRIBUTING.md](CONTRIBUTING.md)


### ♥