# has

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

[![Build Status](https://travis-ci.org/kdabir/has.svg?branch=master)](https://travis-ci.org/kdabir/has)
[![Open Source Helpers](https://www.codetriage.com/kdabir/has/badges/users.svg)](https://www.codetriage.com/kdabir/has)

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

## How ?

[Install](#installing) the `has` script. There is no dependency apart from `bash` itself.

```console
$ has node npm java git gradle
✔ node 8.2.1
✔ npm 5.3.0
✔ java 1.8.0
✔ git 2.14.1
✔ gradle 4.0.1
```

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

```console
$ has node go javac
✔ node 8.2.1
✔ go 1.8.3
✘ javac
```

And echo the status:

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

## Installing

`has` is a single bash script that does it all. Just [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.

### 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`)

### 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 2.17.1
✔ node 11.11.0
✔ npm 6.7.0
```

**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 2.17.1
$ 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 existance of `foobar` and tries to detect version as well.

## 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 2.19.1
✔ curl 7.54.0
✔ ruby 2.3.1
✔ node 10.7.0
```

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 11.0.1
✔ git 2.19.1
✔ curl 7.54.0
✔ ruby 2.3.1
✔ node 10.7.0
```

**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.

## Contributing

1. Star the repo, tweet about it, spread the word
2. Update the documentation (i.e. the README file)
3. Adding support for more commands
4. Adding more features to `has`

## Adding Features

If you are contributing a feature, please ensure to check current tests. Add test cases for your feature. Tests are
executed using the excellent [bats](https://github.com/bats-core/bats-core) testing framework. Add tests and run `make test`

Raise the PR and **make sure the tests pass** on [Travis-CI](https://travis-ci.org/kdabir/has).

### ♥