has checks presence of various command line tools on the PATH and reports their installed version.
Just install 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:
$ 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 exit status code reflects number of commands not found on your path.
$ has node go javac ✔ node 8.2.1 ✔ go 1.8.3 ✘ javac
And echo the status:
$ echo $? 1
has in scripts
has can be used in shell scripts to check presence of tool in very readable way
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 ...
has is a single bash script that does it all. You can download the script and make it available on your
$PATH. However, to make it even simpler, just follow one of these methods.
Just run the following:
brew install kdabir/tap/has
Cloning the Repo
Just execute the following command in a terminal: it clones
has repo and installs it into your path.
git clone https://github.com/kdabir/has.git && cd has && sudo make install
For a non-root installation:
git clone https://github.com/kdabir/has.git cd has make PREFIX=$HOME/.local install
To update just do a
git fetch or
make update followed by the appropriate
make install command.
Downloading to a file
curl -sL https://git.io/_has > /usr/local/bin/has
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
Running directly off the Internet
If you are lazy, you can run
has directly off the Internet as well:
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
alias has="curl -sL https://git.io/_has | bash -s"
And use it
$ 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?
$ has foobar returns
foobar not understood, because
has may not have whitelisted
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 value must exactly be
yfor it to work.
has looks for
.hasrc file in the directory from where
has command is issued. This file can contain commands that
will check for. List one command per line. Lines starting with
# are treated as comments.
Following is example of
# tools git curl # interpreters ruby node
has is run in directory containing this file, it produces:
$ 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
$ 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 file for this repo.
- Star the repo, tweet about it, spread the word
- Update the documentation (i.e. the README file)
- Adding support for more commands
- Adding more features to
Adding more tools
The current list of supported packages can be viewed with
If the command you wish to include supports any of
-V then you can find
corresponding function which can be called to check presence and extract version. However, for many tools version
extraction may not work and you will need to add custom parsing of command's output. The
has script is commented
to guide developers about what needs to be done to add more tools.
/tests/test_all_packages.bats will test every package has supports. This includes newly added commands so please add new packages to
ubuntu.Dockerfileto install the tool OR
packages_ubuntu_skip.txtto exclude the package from the tests
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 testing framework. Add tests and run
Raise the PR and make sure the tests pass on Travis-CI.