Snippet compiler PoC

Author: pikinier20

scaladoc/src/dotty/tools/scaladoc/snippets/SnippetChecker.scala

@@ -0,0 +1,13 @@
+package dotty.tools.scaladoc
+package snippets
+
+import dotty.tools.scaladoc.DocContext
+
+class SnippetChecker(
+  private val compiler: SnippetCompiler = SnippetCompiler(),
+  private val wrapper: SnippetWrapper = SnippetWrapper()
+):
+  def checkSnippet(snippet: String) = {
+    val wrapped = wrapper.wrap(snippet)
+    compiler.compile(snippet)
+  }

scaladoc/src/dotty/tools/scaladoc/snippets/SnippetCompiler.scala

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+package dotty.tools.scaladoc
+package snippets
+
+import dotty.tools.io.{AbstractFile, VirtualDirectory}
+import dotty.tools.dotc.interactive.InteractiveDriver
+import dotty.tools.dotc.interactive.Interactive
+import dotty.tools.dotc.interactive.InteractiveCompiler
+import dotty.tools.dotc.core.Contexts.Context
+import dotty.tools.dotc.config.Settings.Setting._
+import dotty.tools.dotc.interfaces.SourcePosition
+import dotty.tools.dotc.ast.Trees.Tree
+import dotty.tools.dotc.interfaces.{SourceFile => ISourceFile}
+import dotty.tools.dotc.reporting.{ Diagnostic, StoreReporter }
+import dotty.tools.dotc.parsing.Parsers.Parser
+import dotty.tools.dotc.{ Compiler, Run }
+import dotty.tools.io.{AbstractFile, VirtualDirectory}
+import dotty.tools.repl.AbstractFileClassLoader
+import dotty.tools.dotc.util.SourceFile
+
+class SnippetCompiler(
+  classpath: String = System.getProperty("java.class.path"), //Probably needs to be done better
+  val scalacOptions: String = "",
+  target: AbstractFile = new VirtualDirectory("(memory)")
+):
+
+  private def newDriver: InteractiveDriver = {
+    val defaultFlags =
+      List("-color:never", "-unchecked", "-deprecation", "-Ximport-suggestion-timeout", "0")
+    val options = scalacOptions.split("\\s+").toList
+    val settings =
+      options ::: defaultFlags ::: "-classpath" :: classpath :: Nil
+    new InteractiveDriver(settings)
+  }
+
+  private val driver = newDriver
+
+  private val scala3Compiler = new Compiler
+
+  private def newRun(using ctx: Context): Run = scala3Compiler.newRun
+
+  private def nullableMessage(msgOrNull: String): String =
+    if (msgOrNull == null) "" else msgOrNull
+
+  private def createReportMessage(diagnostics: Seq[Diagnostic]): Left[SnippetCompilerException, AbstractFile] = {
+    val infos = diagnostics.toSeq.sortBy(_.pos.source.path)
+    val errorMessages = infos.map {
+      case diagnostic if diagnostic.position.isPresent =>
+        val pos = diagnostic.position.get
+        val msg = nullableMessage(diagnostic.message)
+        SnippetCompilerMessage(pos.line, pos.column, pos.lineContent, msg)
+      case d => SnippetCompilerMessage(-1, -1, "", nullableMessage(d.message))
+    }
+    Left(
+      SnippetCompilerException(errorMessages)
+    )
+  }
+
+  def compile(
+    snippets: List[String]
+  ): Either[SnippetCompilerException, AbstractFile] = {
+    val context = driver.currentCtx.fresh
+      .setSetting(
+        driver.currentCtx.settings.outputDir,
+        target
+      )
+      .setReporter(new StoreReporter)
+    val run = newRun(using context)
+    run.compileFromStrings(snippets)
+    if context.reporter.hasErrors then createReportMessage(context.reporter.allErrors)
+    else Right(target)
+  }
+
+  def compile(
+    snippet: String
+  ): Either[SnippetCompilerException, AbstractFile] = compile(List(snippet))
+
+

scaladoc/src/dotty/tools/scaladoc/snippets/SnippetWrapper.scala

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+package dotty.tools.scaladoc
+package snippets
+
+class SnippetWrapper:
+  def wrap(str: String): String = s"""
+  |package snippets
+  |object Snippet {
+  |  $str
+  |}
+  |""".stripMargin

scaladoc/src/dotty/tools/scaladoc/snippets/exceptions.scala

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+package dotty.tools.scaladoc
+package snippets
+
+case class SnippetCompilerMessage(line: Int, column: Int, sourceLine: String, message: String)
+
+class SnippetCompilerException(messages: Seq[SnippetCompilerMessage]) extends Exception:
+  override def getMessage: String = "Snippet compiler failed to compile with errors:\n"
+   + messages.map(m => s"At ${m.line}:${m.column}:\n${m.sourceLine}Got error: ${m.message}").mkString("\n")

scaladoc/test/dotty/tools/scaladoc/snippets/SnippetCompilerTest.scala

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+package dotty.tools.scaladoc
+package snippets
+
+import org.junit.Test
+import org.junit.Assert._
+import dotty.tools.io.{AbstractFile, VirtualDirectory}
+
+class SnippetCompilerTest {
+  val compiler = SnippetCompiler()
+  def runTest(str: String) = compiler.compile(str)
+
+  def runTest(str: List[String]) = compiler.compile(str)
+
+  def assertSuccessfulCompilation(str: String) = runTest(str) match {
+    case Right(v) => assert(true)
+    case Left(ex) => assert(false, ex.getMessage)
+  }
+
+  def assertFailedCompilation(str: String) = runTest(str) match {
+    case Right(v) => assert(false, "Expected compilation failure")
+    case Left(ex) => assert(true)
+  }
+
+  def assertSuccessfulCompilation(str: List[String]) = runTest(str) match {
+    case Right(v) => assert(true)
+    case Left(ex) => assert(false, ex.getMessage)
+  }
+
+  def assertFailedCompilation(str: List[String]) = runTest(str) match {
+    case Right(v) => assert(false, "Expected compilation failure")
+    case Left(ex) => assert(true)
+  }
+
+  @Test
+  def snippetCompilerTest: Unit = {
+    val simpleCorrectSnippet = s"""
+      |package asd
+      |class A:
+      |  val b: String = "asd"
+      |""".stripMargin
+
+    val simpleIncorrectSnippet = s"""
+      |package asd
+      |class A:
+      |  val b: String
+      |""".stripMargin
+    assertSuccessfulCompilation(simpleCorrectSnippet)
+    assertFailedCompilation(simpleIncorrectSnippet)
+    assertFailedCompilation(List(simpleCorrectSnippet, simpleCorrectSnippet))
+  }
+}