Hey guys, using pants v1, I'd like to add a shell script test to ensure it passes basic tests... how would my BUILD file look like ? I would like to use

bash -n

<scriptname> ? Also, any way I can do more tests like validate output of running flags for the script on the command line?

hey @happy-fish-67882!

any pointers on how to get started ?

the v2 plugin docs are at https://www.pantsbuild.org/docs/plugins-overview

Need v1 for now

the docs for v1 are still around, but we would recommend trying to get on v2 before writing the plugin, as things have changed fundamentally. one sec. lemme find.

Cool! The problem we have is that v2 doesn't seem to support what we need for other languages

I’d like to add a shell script test to ensure it passes basic test

Might it be possible to write a light-weight Python wrapper that calls the relevant bash commands with

subprocess.run()

, then running that via

./pants test

and a

python_tests()

target?

@happy-fish-67882: ah, yea… which languages?

For v2 -- node and scala don't seem supported

got it. yea, that’s correct. JVM support is pretty high on the priority list to be added to 2.0.0: node might be a little while longer.

but in v1, test didn’t depend on binary, so your binary might not be available

True. But in v1, expressing that type of dependency between

test

and

binary

is non-trivial, right? That was a prime reason we implemented the v2 engine in the first place Martin, how feasible would it be to have an outer bash script that calls several Pants commands to achieve what you’re hoping for? Very clunky indeed, but I don’t want to lead you astray with a v1 plugin if you don’t need it. They’re harder to write and not as well documented

@happy-fish-67882: do you know if you are using “source dependencies” for node?

@hundreds-father-404 yeah it's feasible... we could have it execute into some CI system on build

For v2 -- node and scala don’t seem supported

Are you using Python too? It’s possible to set it up so that the Python portion of your repo uses Pants 2.0+, but the rest of your repo still uses 1.30 Not sure if the functionality you’re looking for is around Scala/Node, though. If so, probably not helpful. https://www.pantsbuild.org/docs/how-to-upgrade-pants-2-0#step-2-setup-jvm-node-and-go-support-if-relevant

@hundreds-father-404 but what pants command would those be to do what I'd like to wrt bash script inclusion/testing though

I don't believe we're using it @witty-crayon-22786

ok, thanks.

We could have that test run in a python script, yeah

Cool, so then you can avoid writing a plugin for now, regardless of v1 or v2.

but what pants command would those be to do what I’d like to wrt bash script inclusion/testing though

This is the part we gotta figure out. I’m trying to understand your workflow. Are you hoping to do something like this?

$ ./pants package path/to:tgt
$ result=$(dist/result.pex arg1 --arg2)
$ assert result == foo

Nice! And yeah I'm trying to understand pants 🙂 I guess we'll meet in the center at some point lol

The result of running

./pants bundle

or

./pants binary

. Both of those got consolidated into

./pants package

in 2.0 Generally, I’m trying to see if this is what you’re hoping to do: build a binary with Pants, then run a script that does something with that built artifact, such as testing that it works correctly. Something like this: https://www.pantsbuild.org/v2.2/docs/python-test-goal#depending-on-packages

I can tell you it installs ansible and deps, deploys a kubernetes cluster all by itself, including a custom application. It's a couple of thousand lines

Okay, thanks. I think Stu and I might have been a little confused then with mentioning

./pants binary

- sounds like a red herring. Sorry about that Taking a step back, you have

<myscript.sh>

, and the goal is to use Pants to test that

<myscript.sh>

works properly. Is that right? You are not trying to rewrite

<myscript.sh>

, only test is.

correct

Cool, so then, I would recommend that idea of writing a Python test that calls

myscript.sh

import subprocess

def test_script():
  result = subprocess.run(["myscript.sh", "arg1"], stdout=suprocess.PIPE, ...)
  assert "foo" in result.stdout.decode()

Then, you could use a

python_tests()

target to have Pants always run these tests. How does that sound?

Sounds about right yeah

Awesome. So that will allow you to test the script without needing a plugin, nor needing to upgrade to v2 Pants if aren’t yet able to. The Python code will go into an actual Python file, which can be placed anywhere you want. For example,

<build root>/test_myscript.py

, or some people like to have a

build-support

folder for things like this. Wherever you define that Python file, you’ll have a BUILD file with a target like this in it:

python_tests(name="tests")

ok cool!

Cool, let us know how that goes.

Goal would be to flag through pants if there’s any syntax errors in it,

Have you heard of Shellcheck? Our example plugin repo has an implementation of it. If you’re interested, we can help wire it up into your repo - mostly just copy pasta 🙂 Shellcheck has saved me so much headache We also have implemented a unit testing framework for bash called shunit2

Haven't heard before, what's the url ?

Couple links that might be helpful: + Excellent blog on how to use `subprocess.run`: https://codecalamity.com/run-subprocess-run/ + shellcheck: https://github.com/koalaman/shellcheck + overview of Pants plugins, particularly how they’re loaded https://www.pantsbuild.org/v2.0/docs/plugins-overview + example plugin repo: https://github.com/pantsbuild/example-plugin For the last two, I wouldn’t worry about them yet until you’ve tried out Shellcheck and confirm you want to use it in your project. No sense in seeing how to write a plugin until you know you want the underlying functionality

oh wow, shellcheck is amazing -- thanks for that