Scala Snippet Checker

A Github Action to run Scala Script snippet code in issues.

It detects scala code in issues and comments. Each snippet must be annotated with scala-cli after backtick.

In the background, it uses ScalaCLI to run Scala code.

Annotate snippet of code

There are a few ways to annotate snippet of code to run:

• ```scala-cli
• ```scala-cli args
• ```scala scala-cli
• ```scala ... scala-cli
• ```scala ... scala-cli args

scala-cli keyword must be added to the end of header of a snippet. To pass arguments to ScalaCLI, add them after scala-cli.

Usage:

For now, it is only available in a Linux environment. Windows and MacOs will be supported in the future.

on:
  issue_comment:
    types: [created, edited]
  issues:
    types: [opened, edited]

jobs:
   snippet-runner:
     timeout-minutes: 2
     runs-on: "ubuntu-latest"
     steps:
     - uses: virtuslab/scala-snippet-checker@main

It is recommended to specify a low execution time in timeout minutes.

Examples

test03

```scala-cli
println("Hello30")
```

test02

```scala-cli
// using scala "3.1.0"
// using lib "com.lihaoyi::os-lib:0.7.8"

println(os.pwd)
println("Hello9")
```

will generate a new comment:

In: https://github.com/org/repo/issues/1 Found following snippets:

Snippet:

println("Hello30")

Output:

Compiling project (Scala 3.0.2, JVM)
Compiled project (Scala 3.0.2, JVM)
Hello30

Snippet:

// using scala "3.1.0"
// using lib "com.lihaoyi::os-lib:0.7.8"

println(os.pwd)
println("Hello9")

Output:

Compiling project (Scala 3.1.0, JVM)
Compiled project (Scala 3.1.0, JVM)
/home/runner/work/snippet-runner/snippet-runner
Hello9

Nightly checker

Use nightly checker to find the latest nightly that worked with the input snippet

⚠️ For now, nightly checker works only with Scala 3

Annotate snippet of code for nightly checker

There are a few ways to annotate snippet of code to run:

• ```scala-cli nightly-checker
• ```scala-cli args nightly-checker
• ```scala scala-cli nightly-checker
• ```scala ... scala-cli nightly-checker
• ```scala ... scala-cli args nightly-checker

Examples Nightly Checker

```scala-cli nightly-checker
//> using scala "3.1.2"
// //> using scala "3.1.1" // Last working stable version

def test() = {
  func(_ => Box(Seq.empty[String]) )
}

def func[R0](to0: Unit => R0): Unit = ???

trait JsonFormat[T]
object JsonFormat{
  implicit def immSeqFormat: JsonFormat[Seq[String]]  = ???

  implicit def iterableFormat: JsonFormat[Iterable[String]]   = ??? 
}

case class Box[A1: JsonFormat](elem: A1)
```

will generate a new comment:

In: https://github.com/org/repo/issues/1 Found following snippets:

Snippet:

//> using scala "3.1.2"
// //> using scala "3.1.1" // Last working stable version

def test() = {
 func(_ => Box(Seq.empty[String]) )
}

def func[R0](to0: Unit => R0): Unit = ???

trait JsonFormat[T]
object JsonFormat{
 implicit def immSeqFormat: JsonFormat[Seq[String]]  = ???

 implicit def iterableFormat: JsonFormat[Iterable[String]]   = ??? 
}

case class Box[A1: JsonFormat](elem: A1)

Output:

Found the latest nightly version working with the snippet code: 3.1.2-RC1-bin-20211213-8e1054e-NIGHTLY