Add support for SN 0.4.1 and 0.4.2

Add support for 0.4.0 and 0.4.1 by build.sbt defined values with
defined values, the idea  being that after release 0.4.0 specific code
will be removed and shared and 0.4.1 merged.

Cli arguments are parsed via case-app and additional NativeConfig
generation phase is introduced.

Includes initial project definition and testing infrastructure.
Testing is comprised of scalatest unit tests and sbt-provided scripted
tests acting as integration tests.

Author: jchyb

.github/workflows/CI.yml

@@ -0,0 +1,16 @@
+name: CI
+on:
+  pull_request:
+    push:
+    branches:
+      - master
+jobs:
+  test-all:
+    runs-on: ubuntu-18.04
+      steps:
+        - uses: actions/checkout@v2
+        - uses: olafurpg/setup-scala@v13
+        - name: Unit tests
+          run: sbt cli/test
+        - name: Intergration tests
+          run: sbt cliIntegration/scripted

.github/workflows/check-cla.yml

@@ -0,0 +1,9 @@
+# Copy/pasted from https://github.com/scala-native/scala-native 
+name: Check CLA
+on: [pull_request]
+jobs:
+  check-cla:
+    runs-on: ubuntu-18.04
+    steps:
+      - uses: actions/checkout@v2
+      - run: ./scripts/check-cla.sh

.github/workflows/check-lint.yml

@@ -0,0 +1,19 @@
+# Copy/pasted from https://github.com/scala-native/scala-native 
+name: Check Lint
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+jobs:
+  check-lint:
+    runs-on: ubuntu-18.04
+    steps:
+      - name: Install clang-format
+        run: |
+          sudo apt update
+          sudo apt install clang-format-6.0
+      - uses: actions/checkout@v2
+      - run: ./scripts/check-lint.sh
+        env:
+          CLANG_FORMAT_PATH: "/usr/bin/clang-format-6.0"

.gitignore

@@ -0,0 +1,29 @@
+**/target/
+
+scripts/.coursier
+scripts/.scalafmt*
+
+# IntelliJ
+.idea
+
+# Eclipse / Scala IDE
+bin/
+.project
+.classpath
+.settings/
+.externalToolBuilders/
+.cache*
+
+# metals
+**/.bloop/
+**/.metals/
+/project/**/metals.sbt
+
+# Build Server Protocol, used by sbt
+/.bsp/
+
+# vscode
+/.vscode/
+
+# vim
+*.swp

.scalafmt.conf

@@ -0,0 +1,3 @@
+version = "3.2.1"
+runner.dialect = scala212
+project.git = true

README.md

@@ -1,2 +1,41 @@
 # scala-native-cli
-Command Line Interface for Scala Native
+
+Command Line Interface for the tools component of Scala Native. Tools handle the linking, optimisation and code generation phases. 
+This means that the initial .scala files cannot be compiled with it - for that look to the nscplugin component. 
+
+Please note that this api is meant for Scala Native power users. For a more friendly Scala Native building experience please use 
+the dedicated [sbt plugin](https://scala-native.readthedocs.io/en/stable/user/sbt.html#minimal-sbt-project) or [scala-cli](https://scala-cli.virtuslab.org).
+
+## Usage
+
+scala-native-cli --help will bring up possible options and syntax. 
+Since options are dependent on the used version of scala-native-cli, please use it for further instructions.
+
+### Passing link-time resolved properties
+
+Scala Native allows use of link-time properties - values that are used to resolve `if` code blocks on link-time. 
+Their non-standard format requires special care. 
+
+In scala-native-cli their value is defined as follows:
+
+```keystring=[Type]value```
+
+`keystring` is always a string, however value has to have a type specified in the square brackets. It can be one of the following:
+
+* `Short`
+* `Int`
+* `Long`
+* `Float`
+* `Double`
+* `Char`
+* `Boolean`
+* `String`
+
+## Logging 
+
+For logging purposes, a default Scala Native logger is used. It is possible to specify which messages to log by filtering out the unnecessary ones with the following options:
+
+* `--disable-debug`
+* `--disable-info`
+* `--disable-warn`
+* `--disable-error`

build.sbt

@@ -0,0 +1,55 @@
+scalaVersion := "2.12.15"
+val nativeVersion = "0.4.1"
+val cliVersion = nativeVersion
+
+inThisBuild(
+  Def.settings(
+    organization := "org.scala-native",
+    version := cliVersion
+  )
+)
+
+lazy val cli = project
+  .in(file(s"cli/version_${nativeVersion}"))
+  .settings(
+    moduleName := "scala-native-cli",
+    scalacOptions += "-Ywarn-unused:imports",
+    libraryDependencies += "org.scala-native" %% "tools" % nativeVersion,
+    libraryDependencies += "com.github.alexarchambault" %% "case-app" % "2.1.0-M9",
+    libraryDependencies += "org.scalatest" %% "scalatest" % "3.1.1" % Test,
+    assembly / assemblyJarName := "scala-native-cli.jar", // Used for integration tests.
+    Compile / unmanagedSourceDirectories += baseDirectory.value.getParentFile / "shared/src/main/scala",
+    Test / unmanagedSourceDirectories += baseDirectory.value.getParentFile / "shared/src/test/scala"
+  )
+
+// Meant to resolve classpath dependencies, provide compiled nir
+// and a seperate environment for integration tests
+lazy val cliIntegration = project
+  .in(file("scala-native-cli-integration-test-runner"))
+  .enablePlugins(SbtPlugin)
+  .settings(
+    name := "scala-native-cli-integration-test-runner",
+    scriptedLaunchOpts := {
+      val cliPath =
+        (cli / Compile / packageBin / artifactPath).value.toPath.getParent.toString + "/scala-native-cli.jar"
+      scriptedLaunchOpts.value ++
+        Seq(
+          "-Xmx1024M",
+          "-Dplugin.version=" + version.value,
+          "-Dscala-native-cli=" + cliPath,
+          "-Dscala-native-cli-native-version=" + nativeVersion
+        )
+    },
+    addSbtPlugin("org.portable-scala" % "sbt-platform-deps" % "1.0.0"),
+    sbtTestDirectory := (ThisProject / baseDirectory).value / "src/test",
+    // publish the other projects before running scripted tests.
+    scriptedDependencies := {
+      scriptedDependencies
+        .dependsOn(
+          cli / assembly
+        )
+        .value
+    },
+    scriptedBufferLog := false
+  )
+  .dependsOn(cli)

cli/shared/src/main/scala/scala/scalanative/cli/ScalaNativeCli.scala

@@ -0,0 +1,23 @@
+package scala.scalanative.cli
+
+import scala.scalanative.build.Build
+import scala.scalanative.util.Scope
+import System._
+import scala.scalanative.cli.utils.{BuildOptionsParser, BuildOptions}
+
+object ScalaNativeCli {
+  def main(options: Array[String]): Unit = {
+    val configOption = BuildOptionsParser(options)
+
+    configOption match {
+      case Right(Some(BuildOptions(config, outpath))) =>
+        Scope { implicit scope =>
+          Build.build(config, outpath)
+        }
+      case Left(exception) =>
+        err.println(exception.getMessage())
+        sys.exit(1)
+      case Right(None) => // when --help or --version
+    }
+  }
+}

cli/shared/src/main/scala/scala/scalanative/cli/options/CliOptions.scala

@@ -0,0 +1,14 @@
+package scala.scalanative.cli.options
+
+import caseapp._
+
+@AppName("Scala Native Cli")
+@ProgName("scala-native-cli")
+case class CliOptions(
+    @Recurse
+    config: ConfigOptions,
+    @Recurse
+    nativeConfig: NativeConfigOptions,
+    @Recurse
+    logger: LoggerOptions
+)

cli/shared/src/main/scala/scala/scalanative/cli/options/ConfigOptions.scala

@@ -0,0 +1,26 @@
+package scala.scalanative.cli.options
+
+import caseapp._
+
+case class ConfigOptions(
+    @Group("Config")
+    @HelpMessage(
+      "Required path of the resulting output binary. [./scala-native-out]"
+    )
+    @ValueDescription("<output-path>")
+    outpath: String = "scala-native-out",
+    @Group("Config")
+    @HelpMessage(
+      "Required sequence of all linked NIR files. Should include the standard Scala Native libraries."
+    )
+    @ValueDescription("<colon-separated-file-paths>")
+    classPath: String,
+    @Group("Config")
+    @HelpMessage("Required entry point for linking.")
+    @ValueDescription("<main-class>")
+    main: String,
+    @Group("Config")
+    @HelpMessage("Scala Native working directory. [.]")
+    @ValueDescription("<path-to-directory>")
+    workdir: String = "."
+)