feat: add option flag, greedy compilation of multiple files, and refactor to use paths instead of files

src/main/wacc/Main.scala

@@ -1,10 +1,11 @@
 package wacc
 
 import scala.collection.mutable
-import cats.data.Chain
+import cats.data.{Chain, NonEmptyList}
 import parsley.{Failure, Success}
-import java.io.File
-import cats.implicits.*
+
+import java.nio.file.{Files, Path, Paths}
+import cats.syntax.all._
 
 import cats.effect.IO
 import cats.effect.ExitCode
@@ -18,24 +19,30 @@ import org.typelevel.log4cats.Logger
 
 import assemblyIR as asm
 
-given Argument[File] = Argument.from("file") { str =>
-  val file = File(str)
+
+// TODO: IO correctness, --greedy, parallelisable, and probably splitting this file up
+
+
+given Argument[Path] = Argument.from("path") { str =>
+  val path = Path.of(str)
   (
-    Option.when(file.exists())(file).toValidNel(s"File '${file.getAbsolutePath}' does not exist"),
-    Option
-      .when(file.isFile())(file)
-      .toValidNel(s"File '${file.getAbsolutePath}' must be a regular file"),
-    Option.when(file.getName.endsWith(".wacc"))(file).toValidNel("File must have .wacc extension")
-  ).mapN((_, _, _) => file)
+    Either.cond(Files.exists(path), path, s"File '${path.toAbsolutePath}' does not exist"),
+    Either.cond(Files.isRegularFile(path), path, s"File '${path.toAbsolutePath}' must be a regular file"),
+    Either.cond(path.toString.endsWith(".wacc"), path, "File must have .wacc extension")
+  ).mapN((_, _, _) => path).toValidatedNel
 }
 
-val cliCommand: Command[File] =
-  Command("wacc-compiler", "Compile WACC programs") {
-    Opts.argument[File]("file")
-  }
-
 given logger: Logger[IO] = Slf4jLogger.getLogger[IO]
 
+val logOpt: Opts[Boolean] =
+  Opts.flag("log", "Enable logging for additional compilation details", short = "l").orFalse
+
+val outputOpt: Opts[Option[Path]] =
+  Opts.option[Path]("output", "Specify path for output assembly file(s)").orNone
+
+val filesOpt: Opts[NonEmptyList[Path]] = Opts.arguments[Path]("files")
+
+
 def frontend(
     contents: String
 ): IO[Either[Int, microWacc.Program]] = {
@@ -51,55 +58,73 @@ def frontend(
 
       val typedProg = typeChecker.check(prog)
 
-      if (errors.result.isEmpty) IO.pure(Right(typedProg))
+      val errResult = errors.result
+
+      if (errResult.isEmpty) IO.pure(Right(typedProg))
       else {
+        // TODO: multiple traversal of error content, should be a foldleft or co
         given errorContent: String = contents
-        val exitCode = errors.result.view.map {
+        val exitCode = errResult.collectFirst {
           case _: Error.InternalError => 201
-          case _                      => 200
-        }.max
+        }.getOrElse(200)
 
-        val formattedErrors = errors.result.map(formatError).mkString("\n")
+        val formattedErrors = errResult.map(formatError).mkString("\n")
 
-        logger.error(s"Semantic errors:\n$formattedErrors") *> IO.pure(Left(exitCode))
+        logger.error(s"Semantic errors:\n$formattedErrors").as(Left(exitCode))
       }
   }
 }
 
-val s = "enter an integer to echo"
 def backend(typedProg: microWacc.Program): Chain[asm.AsmLine] =
   asmGenerator.generateAsm(typedProg)
 
-def compile(filename: String, outFile: Option[File] = None): IO[Int] =
+// TODO: filename being String seems unnatural due to Path refactor
+// TODO: this function is doing too much should refactor
+def compile(filename: String, outputDir: Option[Path], log: Boolean): IO[Int] =
+  val logAction: String => IO[Unit] =
+    if (log) logger.info(_)
+    else (_ => IO.unit)
   for {
-    contents <- IO(os.read(os.Path(filename)))
-    _ <- logger.info(s"Compiling file: $filename")
+    contents <- IO.delay(os.read(os.Path(filename))) // TODO: Is IO as a wrapper ok or do we require .delay - also, should it be .blocking?
+    _ <- logAction(s"Compiling file: $filename")
     result <- frontend(contents)
     exitCode <- result.fold(
       code => logger.error(s"Compilation failed for $filename\nExit code: $code").as(code),
       typedProg =>
-        val outputFile = outFile.getOrElse(File(filename.stripSuffix(".wacc") + ".s"))
-        writer.writeTo(backend(typedProg), outputFile) *> logger
-          .info(s"Compilation succeeded: $filename")
-          .as(0)
+        val outDir = outputDir.getOrElse(Paths.get(filename).getParent)
+        IO.delay(Files.createDirectories(outDir)) // TODO: Is IO as a wrapper ok or do we require .delay - also, should it be .blocking?
+        val outputFile = outDir.resolve(filename.stripSuffix(".wacc") + ".s")
+        writer.writeTo(backend(typedProg), outputFile) *> // TODO: I dont think we need IO here if we look at the implementation of writer
+        logAction(s"Compilation succeeded: $filename").as(0)
     )
   } yield exitCode
 
+// TODO: this is sequential, thus should be what occurs when --greedy is passed in
+val compileCommand: Opts[IO[ExitCode]] =
+  (filesOpt, logOpt, outputOpt).mapN{
+    (files, log, outDir) =>
+       files
+        .traverse{ file =>
+          compile(
+            file.toAbsolutePath.toString,
+            outDir,
+            log)
+        }.map {
+          exitCodes =>
+            if (exitCodes.exists(_ != 0)) ExitCode.Error // TODO- it should be the first one to exit when parallelised :)
+            else ExitCode.Success
+        }
+
+  }
+
+// TODO: add parallelisable option
 object Main
     extends CommandIOApp(
-      name = "wacc-compiler",
-      header = "the ultimate wacc compiler",
+      name = "wacc",
+      header = "The ultimate WACC compiler",
       version = "1.0"
     ) {
   def main: Opts[IO[ExitCode]] =
-    Opts.arguments[File]("files").map { files =>
-      files
-        .parTraverse_ { file =>
-          compile(
-            file.getAbsolutePath,
-            outFile = Some(File(".", file.getName.stripSuffix(".wacc") + ".s"))
-          )
-        }
-        .as(ExitCode.Success)
-    }
-}
+    compileCommand
+
+}

src/main/wacc/backend/writer.scala

@@ -2,26 +2,26 @@ package wacc
 
 import cats.effect.Resource
 import java.nio.charset.StandardCharsets
-import java.io.File
 import java.io.BufferedWriter
 import java.io.FileWriter
 import cats.data.Chain
 import cats.effect.IO
 
 import org.typelevel.log4cats.Logger
+import java.nio.file.Path
 
 object writer {
   import assemblyIR._
 
-  def writeTo(asmList: Chain[AsmLine], outputFile: File)(using logger: Logger[IO]): IO[Unit] =
+  def writeTo(asmList: Chain[AsmLine], outputPath: Path)(using logger: Logger[IO]): IO[Unit] =
     Resource
       .fromAutoCloseable {
-        IO(BufferedWriter(FileWriter(outputFile, StandardCharsets.UTF_8)))
+        IO(BufferedWriter(FileWriter(outputPath.toFile, StandardCharsets.UTF_8)))
       }
       .use { writer =>
         IO {
           asmList.iterator.foreach(line => writer.write(line.toString + "\n"))
           writer.flush() // TODO: NECESSARY OR NOT?
-        } *> logger.info(s"Wrote assembly to ${outputFile.getAbsolutePath}")
+        } *> logger.info(s"Success: ${outputPath.toAbsolutePath}")
       }
 }