Return build exception to propagate error using EitherCps

Author: lwronski

modules/build/src/main/scala/scala/build/Inputs.scala

@@ -7,6 +7,7 @@ import java.security.MessageDigest
 
 import scala.annotation.tailrec
 import scala.build.Inputs.WorkspaceOrigin
+import scala.build.errors.{BuildException, InputsException}
 import scala.build.internal.Constants
 import scala.build.internal.zip.WrappedZipInputStream
 import scala.build.options.Scope
@@ -414,7 +415,7 @@ object Inputs {
     javaSnippetOpt: Option[String],
     acceptFds: Boolean,
     forcedWorkspace: Option[os.Path]
-  ): Either[String, Inputs] = {
+  ): Either[BuildException, Inputs] = {
     val validatedArgs: Seq[Either[String, Seq[Element]]] =
       validateArgs(args, cwd, download, stdinOpt, acceptFds)
     val validatedExpressions: Seq[Either[String, Seq[Element]]] =
@@ -432,7 +433,7 @@ object Inputs {
       Right(forValidatedElems(validElems, baseProjectName, directories, forcedWorkspace))
     }
     else
-      Left(invalid.mkString(System.lineSeparator()))
+      Left(new InputsException(invalid.mkString(System.lineSeparator())))
   }
 
   def apply(
@@ -448,13 +449,13 @@ object Inputs {
     javaSnippetOpt: Option[String] = None,
     acceptFds: Boolean = false,
     forcedWorkspace: Option[os.Path] = None
-  ): Either[String, Inputs] =
+  ): Either[BuildException, Inputs] =
     if (
       args.isEmpty && scriptSnippetOpt.isEmpty && scalaSnippetOpt.isEmpty && javaSnippetOpt.isEmpty
     )
-      defaultInputs().toRight(
+      defaultInputs().toRight(new InputsException(
         "No inputs provided (expected files with .scala or .sc extensions, and / or directories)."
-      )
+      ))
     else
       forNonEmptyArgs(
         args,

modules/build/src/main/scala/scala/build/bsp/Bsp.scala

@@ -3,6 +3,7 @@ package scala.build.bsp
 import java.io.{InputStream, OutputStream}
 
 import scala.build.Inputs
+import scala.build.errors.BuildException
 import scala.concurrent.Future
 
 trait Bsp {
@@ -12,7 +13,7 @@ trait Bsp {
 
 object Bsp {
   def create(
-    argsToInputs: Seq[String] => Either[String, Inputs],
+    argsToInputs: Seq[String] => Either[BuildException, Inputs],
     bspReloadableOptionsReference: BspReloadableOptions.Reference,
     threads: BspThreads,
     in: InputStream,

modules/build/src/main/scala/scala/build/bsp/BspImpl.scala

@@ -13,7 +13,7 @@ import scala.build.EitherCps.{either, value}
 import scala.build._
 import scala.build.bloop.{BloopServer, ScalaDebugServer}
 import scala.build.compiler.BloopCompiler
-import scala.build.errors.{BuildException, Diagnostic}
+import scala.build.errors.{BuildException, Diagnostic, ParsingInputsException}
 import scala.build.internal.{Constants, CustomCodeWrapper}
 import scala.build.options.{BuildOptions, Scope}
 import scala.collection.mutable.ListBuffer
@@ -23,7 +23,7 @@ import scala.jdk.CollectionConverters._
 import scala.util.{Failure, Success}
 
 final class BspImpl(
-  argsToInputs: Seq[String] => Either[String, Inputs],
+  argsToInputs: Seq[String] => Either[BuildException, Inputs],
   bspReloadableOptionsReference: BspReloadableOptions.Reference,
   threads: BspThreads,
   in: InputStream,
@@ -459,13 +459,13 @@ final class BspImpl(
     val ideInputsJsonPath =
       currentBloopSession.inputs.workspace / Constants.workspaceDirName / "ide-inputs.json"
     if (os.isFile(ideInputsJsonPath)) {
-      val maybeResponse = either[String] {
+      val maybeResponse = either[BuildException] {
         val ideInputs = value {
           try Right(readFromArray(os.read.bytes(ideInputsJsonPath))(IdeInputs.codec))
           catch {
             case e: JsonReaderException =>
               logger.debug(s"Caught $e while decoding $ideInputsJsonPath")
-              Left(e.getMessage)
+              Left(new ParsingInputsException(e.getMessage, e))
           }
         }
         val newInputs      = value(argsToInputs(ideInputs.args))

modules/build/src/test/scala/scala/build/tests/TestInputs.scala

@@ -44,7 +44,7 @@ final case class TestInputs(
         forcedWorkspace = forcedWorkspaceOpt.map(_.resolveFrom(tmpDir))
       )
       res match {
-        case Left(err)     => sys.error(err)
+        case Left(err)     => throw new Exception(err)
         case Right(inputs) => f(tmpDir, inputs)
       }
     }

modules/cli/src/main/scala/scala/cli/commands/Bsp.scala

@@ -3,7 +3,9 @@ package scala.cli.commands
 import caseapp._
 import com.github.plokhotnyuk.jsoniter_scala.core._
 
+import scala.build.EitherCps.{either, value}
 import scala.build.bsp.{BspReloadableOptions, BspThreads}
+import scala.build.errors.BuildException
 import scala.build.options.BuildOptions
 import scala.build.{Build, Inputs}
 import scala.cli.CurrentParams
@@ -25,16 +27,17 @@ object Bsp extends ScalaCommand[BspOptions] {
         readFromArray(content)(SharedOptions.jsonCodec)
       }.getOrElse(options.shared)
 
-    val argsToInputs: Seq[String] => Either[String, Inputs] =
-      argsSeq => {
-        val sharedOptions = getSharedOptions()
-        sharedOptions.inputs(argsSeq, () => Inputs.default())
-          .map { i =>
-            if (sharedOptions.logging.verbosity >= 3)
-              pprint.err.log(i)
-            Build.updateInputs(i, buildOptions(sharedOptions))
-          }
-      }
+    val argsToInputs: Seq[String] => Either[BuildException, Inputs] =
+      argsSeq =>
+        either {
+          val sharedOptions = getSharedOptions()
+          val initialInputs = value(sharedOptions.inputs(argsSeq, () => Inputs.default()))
+
+          if (sharedOptions.logging.verbosity >= 3)
+            pprint.err.log(initialInputs)
+
+          Build.updateInputs(initialInputs, buildOptions(sharedOptions))
+        }
 
     val bspReloadableOptionsReference = BspReloadableOptions.Reference { () =>
       val sharedOptions = getSharedOptions()
@@ -46,7 +49,8 @@ object Bsp extends ScalaCommand[BspOptions] {
       )
     }
 
-    val inputs = getSharedOptions().inputsOrExit(argsToInputs(args.all))
+    val logger = getSharedOptions().logging.logger
+    val inputs = argsToInputs(args.all).orExit(logger)
     CurrentParams.workspaceOpt = Some(inputs.workspace)
     BspThreads.withThreads { threads =>
       val bsp = scala.build.bsp.Bsp.create(

modules/cli/src/main/scala/scala/cli/commands/util/SharedOptionsUtil.scala

@@ -11,8 +11,9 @@ import java.io.{File, InputStream}
 import scala.build._
 import scala.build.blooprifle.BloopRifleConfig
 import scala.build.compiler.{BloopCompilerMaker, ScalaCompilerMaker, SimpleScalaCompilerMaker}
+import scala.build.errors.BuildException
 import scala.build.internal.CsLoggerUtil._
-import scala.build.internal.{Constants, FetchExternalBinary, OsLibc}
+import scala.build.internal.{Constants, FetchExternalBinary, OsLibc, Util}
 import scala.build.options.{Platform, ScalacOpt, ShadowingSeq}
 import scala.build.{options => bo}
 import scala.cli.commands.ScalaJsOptions
@@ -229,9 +230,9 @@ object SharedOptionsUtil {
     ): Inputs =
       inputsOrExit(inputs(args, defaultInputs))
 
-    def inputsOrExit(maybeInputs: Either[String, Inputs]): Inputs = maybeInputs match {
-      case Left(message) =>
-        System.err.println(message)
+    def inputsOrExit(maybeInputs: Either[BuildException, Inputs]): Inputs = maybeInputs match {
+      case Left(exception) =>
+        Util.printException(exception)
         sys.exit(1)
       case Right(i) => i
     }
@@ -252,7 +253,7 @@ object SharedOptionsUtil {
     def inputs(
       args: Seq[String],
       defaultInputs: () => Option[Inputs]
-    ): Either[String, Inputs] = {
+    ): Either[BuildException, Inputs] = {
       val resourceInputs = resourceDirs
         .map(os.Path(_, Os.pwd))
         .map { path =>

modules/core/src/main/scala/scala/build/errors/InputsException.scala

@@ -0,0 +1,6 @@
+package scala.build.errors
+
+class InputsException(message: String)
+    extends BuildException(
+      message = message
+    )

modules/core/src/main/scala/scala/build/errors/ParsingInputsException.scala

@@ -0,0 +1,7 @@
+package scala.build.errors
+
+class ParsingInputsException(exceptionMessage: String, cause: Throwable)
+    extends BuildException(
+      message = exceptionMessage,
+      cause = cause
+    )