How to run and compile exact one test in sbt?

Question

I'm working on a legacy project that has been written in Scala using SBT. The unit tests have been written with ScalaTest. The problem is there is a lot of test classes that have compilation error.

I want to run only one of these test classes and I know for running only one test I should try something like this:

test:testOnly *myClass

But when I run this command, the SBT will try to compile the whole project and as I said, there's a lot of test classes that have compilation error. Is there any way to tell SBT exactly which classes need to be compiled and so the others will be ignored?

Answer 1

You have as mentioned above the next option:

• sbt testOnly *className : This will run all the tests defined in that class.
• sbt testOnly *className-- -z "test-pattern" : It will run all the tests from that class which spec matchs the pattern defined.

Answer 2

Consider defining a single-argument custom command in build.sbt like so

commands += Command.single("compileAndTestOnly") { (state, file) =>
  s"""set sources in Test := (sources in Test).value.filter(_.name.contains("$file"))""" ::
    "test" :: state
}

Now run it with compileAndTestOnly MySpec.scala. This command modifies Test \ sources setting to contain only a single file like so

sources in Test := (sources in Test).value.filter(_.name.contains(file))

Note sources in Compile is left untouched. Afterwards it executes test which in effect compiles and runs a single test.

This answer is inspired by 0__.

Answer 3

It's impossible to instruct sbt to only compile the file that contains the test that matches your name, because it'll only know what name the test has after it's compiled -- in scala a class name and a file name don't have to have anything to do with another.

A source filter is not built-in in sbt. You will need a custom task along the lines of what @mario-galic has above.

Beware though, that will filter based on file name, not on class name.

I agree it would be a neat feature for sbt to run all tests it can even when the compilation of some files were to fail.