Use PPrint to handle printing of REPL output values

compiler/src/dotty/tools/dotc/printing/SyntaxHighlighting.scala

@@ -27,7 +27,7 @@ object SyntaxHighlighting {
   val CommentColor: String    = Console.BLUE
   val KeywordColor: String    = Console.YELLOW
   val ValDefColor: String     = Console.CYAN
-  val LiteralColor: String    = Console.RED
+  val LiteralColor: String    = Console.GREEN
   val StringColor: String     = Console.GREEN
   val TypeColor: String       = Console.MAGENTA
   val AnnotationColor: String = Console.MAGENTA
@@ -80,6 +80,9 @@ object SyntaxHighlighting {
           case IDENTIFIER if name == nme.??? =>
             highlightRange(start, end, Console.RED_B)
 
+          case IDENTIFIER if name.head.isUpper && name.exists(!_.isUpper) =>
+            highlightRange(start, end, KeywordColor)
+
           case _ =>
         }
       }

compiler/src/dotty/tools/repl/Rendering.scala

@@ -26,8 +26,6 @@ private[repl] class Rendering(parentClassLoader: Option[ClassLoader] = None):
 
   var myClassLoader: AbstractFileClassLoader = uninitialized
 
-  /** (value, maxElements, maxCharacters) => String */
-  var myReplStringOf: (Object, Int, Int) => String = uninitialized
 
   /** Class loader used to load compiled code */
   private[repl] def classLoader()(using Context) =
@@ -46,45 +44,6 @@ private[repl] class Rendering(parentClassLoader: Option[ClassLoader] = None):
       }
 
       myClassLoader = new AbstractFileClassLoader(ctx.settings.outputDir.value, parent)
-      myReplStringOf = {
-        // We need to use the ScalaRunTime class coming from the scala-library
-        // on the user classpath, and not the one available in the current
-        // classloader, so we use reflection instead of simply calling
-        // `ScalaRunTime.stringOf`. Also probe for new stringOf that does string quoting, etc.
-        val scalaRuntime = Class.forName("scala.runtime.ScalaRunTime", true, myClassLoader)
-        val renderer = "stringOf"
-        val stringOfInvoker: (Object, Int) => String =
-          def richStringOf: (Object, Int) => String =
-            val method = scalaRuntime.getMethod(renderer, classOf[Object], classOf[Int], classOf[Boolean])
-            val richly = java.lang.Boolean.TRUE // add a repl option for enriched output
-            (value, maxElements) => method.invoke(null, value, maxElements, richly).asInstanceOf[String]
-          def poorStringOf: (Object, Int) => String =
-            try
-              val method = scalaRuntime.getMethod(renderer, classOf[Object], classOf[Int])
-              (value, maxElements) => method.invoke(null, value, maxElements).asInstanceOf[String]
-            catch case _: NoSuchMethodException => (value, maxElements) => String.valueOf(value).take(maxElements)
-          try richStringOf
-          catch case _: NoSuchMethodException => poorStringOf
-        def stringOfMaybeTruncated(value: Object, maxElements: Int): String = stringOfInvoker(value, maxElements)
-
-        // require value != null
-        // `ScalaRuntime.stringOf` returns null iff value.toString == null, let caller handle that.
-        // `ScalaRuntime.stringOf` may truncate the output, in which case we want to indicate that fact to the user
-        // In order to figure out if it did get truncated, we invoke it twice - once with the `maxElements` that we
-        // want to print, and once without a limit. If the first is shorter, truncation did occur.
-        // Note that `stringOf` has new API in flight to handle truncation, see stringOfMaybeTruncated.
-        (value: Object, maxElements: Int, maxCharacters: Int) =>
-          stringOfMaybeTruncated(value, Int.MaxValue) match
-            case null => null
-            case notTruncated =>
-              val maybeTruncated =
-                val maybeTruncatedByElementCount = stringOfMaybeTruncated(value, maxElements)
-                truncate(maybeTruncatedByElementCount, maxCharacters)
-              // our string representation may have been truncated by element and/or character count
-              // if so, append an info string - but only once
-              if notTruncated.length == maybeTruncated.length then maybeTruncated
-              else s"$maybeTruncated ... large output truncated, print value to show all"
-      }
       myClassLoader
     }
 
@@ -95,17 +54,7 @@ private[repl] class Rendering(parentClassLoader: Option[ClassLoader] = None):
 
   /** Return a String representation of a value we got from `classLoader()`. */
   private[repl] def replStringOf(sym: Symbol, value: Object)(using Context): String =
-    assert(myReplStringOf != null,
-      "replStringOf should only be called on values creating using `classLoader()`, but `classLoader()` has not been called so far")
-    val maxPrintElements = ctx.settings.VreplMaxPrintElements.valueIn(ctx.settingsState)
-    val maxPrintCharacters = ctx.settings.VreplMaxPrintCharacters.valueIn(ctx.settingsState)
-    // stringOf returns null if value.toString returns null. Show some text as a fallback.
-    def fallback = s"""null // result of "${sym.name}.toString" is null"""
-    if value == null then "null" else
-      myReplStringOf(value, maxPrintElements, maxPrintCharacters) match
-        case null => fallback
-        case res  => res
-    end if
+    dotty.shaded.pprint.PPrinter.BlackWhite.apply(value).plainText
 
   /** Load the value of the symbol using reflection.
    *

compiler/test-resources/repl/i18383

@@ -11,4 +11,4 @@ scala> class Foo { import scala.util.*; println("foo") }
 // defined class Foo
 
 scala> { import scala.util.*; "foo" }
-val res0: String = foo
+val res0: String = "foo"

compiler/test-resources/repl/i3388

@@ -1,3 +1,3 @@
 scala> val foo = "1"; foo.toInt
-val foo: String = 1
+val foo: String = "1"
 val res0: Int = 1

compiler/test-resources/repl/jar-multiple

@@ -7,26 +7,26 @@ Added 'compiler/test-resources/jars/mylibrary.jar' to classpath.
 scala> import mylibrary.Utils
 
 scala> Utils.greet("Alice")
-val res0: String = Hello, Alice!
+val res0: String = "Hello, Alice!"
 
 scala>:jar compiler/test-resources/jars/mylibrary2.jar
 Added 'compiler/test-resources/jars/mylibrary2.jar' to classpath.
 
 scala> import mylibrary2.Utils2
 
 scala> Utils2.greet("Alice")
-val res1: String = Greetings, Alice!
+val res1: String = "Greetings, Alice!"
 
 scala> Utils.greet("Alice")
-val res2: String = Hello, Alice!
+val res2: String = "Hello, Alice!"
 
 scala> import mylibrary.Utils.greet
 
 scala> greet("Tom")
-val res3: String = Hello, Tom!
+val res3: String = "Hello, Tom!"
 
 scala> Utils.greet("Alice")
-val res4: String = Hello, Alice!
+val res4: String = "Hello, Alice!"
 
 scala> z
 val res5: Int = 1

compiler/test/dotty/tools/dotc/printing/SyntaxHighlightingTests.scala

@@ -95,7 +95,7 @@ class SyntaxHighlightingTests extends DottyTest {
     test("val foo = 123", "<K|val> <V|foo> = <L|123>")
     test(
       "val foo: List[List[Int]] = List(List(1))",
-      "<K|val> <V|foo>: <T|List>[<T|List>[<T|Int>]] = List(List(<L|1>))"
+      "<K|val> <V|foo>: <T|List>[<T|List>[<T|Int>]] = <K|List>(<K|List>(<L|1>))"
     )
 
     test("var",                "<K|var>")

compiler/test/dotty/tools/repl/LoadTests.scala

@@ -20,7 +20,7 @@ class LoadTests extends ReplTest {
                  |def helloWorld: String
                  |""".stripMargin,
     runCode = "helloWorld",
-    output  = """|val res0: String = Hello, World!
+    output  = """|val res0: String = "Hello, World!"
                  |""".stripMargin
   )
 

compiler/test/dotty/tools/repl/ReplCompilerTests.scala

@@ -262,7 +262,7 @@ class ReplCompilerTests extends ReplTest:
 
   @Test def testSingletonPrint = initially {
     run("""val a = "hello"; val x: a.type = a""")
-    assertMultiLineEquals("val a: String = hello\nval x: a.type = hello", storedOutput().trim)
+    assertMultiLineEquals("val a: String = \"hello\"\nval x: a.type = \"hello\"", storedOutput().trim)
   }
 
   @Test def i6574 = initially {
@@ -445,7 +445,6 @@ class ReplCompilerTests extends ReplTest:
     .andThen:
       val last = lines().last
       assertTrue(last, last.startsWith("val tpolecat: Object = null"))
-      assertTrue(last, last.endsWith("""// result of "tpolecat.toString" is null"""))
 
   @Test def `i17333 print toplevel object with null toString`: Unit =
     initially:
@@ -454,7 +453,6 @@ class ReplCompilerTests extends ReplTest:
       run("tpolecat")
       val last = lines().last
       assertTrue(last, last.startsWith("val res0: tpolecat.type = null"))
-      assertTrue(last, last.endsWith("""// result of "res0.toString" is null"""))
 
   @Test def `i21431 filter out best effort options`: Unit =
     initially:

compiler/test/dotty/tools/repl/ShadowingTests.scala

@@ -131,7 +131,7 @@ class ShadowingTests extends ReplTest(options = ShadowingTests.options):
     testScript(name = "<shadow-subdir-x>",
       """|scala> val (x, y) = (42, "foo")
          |val x: Int = 42
-         |val y: String = foo
+         |val y: String = "foo"
          |
          |scala> if (true) x else y
          |val res0: Int | String = 42

language-server/test/dotty/tools/languageserver/WorksheetTest.scala

@@ -90,7 +90,7 @@ class WorksheetTest {
           case _ => "odd"
         }${m2}"""
       .run(m1,
-        ((m1 to m2), "val res0: String = odd"))
+        ((m1 to m2), "val res0: String = \"odd\""))
   }
 
   @Test def evaluationException: Unit = {

project/Build.scala

@@ -675,6 +675,94 @@ object Build {
     recur(lines)
   }
 
+  val shadedSourceGenerator = (Compile / sourceGenerators) += Def.task {
+    val downloads = Seq(
+      "https://repo1.maven.org/maven2/com/lihaoyi/pprint_3/0.9.3/pprint_3-0.9.3-sources.jar",
+      "https://repo1.maven.org/maven2/com/lihaoyi/fansi_3/0.5.1/fansi_3-0.5.1-sources.jar",
+      "https://repo1.maven.org/maven2/com/lihaoyi/sourcecode_3/0.4.3-M5/sourcecode_3-0.4.3-M5-sources.jar",
+    )
+    val dest = ((Compile / sourceManaged).value / "downloaded").toPath
+    if (Files.exists(dest)) {
+      Files.walk(dest)
+        .sorted(java.util.Comparator.reverseOrder()) // delete children before parents
+        .forEach(p => Files.delete(p));
+    }
+    Files.createDirectories(dest)
+
+    for(url <- downloads) {
+      import java.io._
+      import java.net.{HttpURLConnection, URL}
+      import java.nio.file._
+      import java.nio.file.attribute.FileTime
+      import java.util.zip.{ZipEntry, ZipInputStream}
+
+      val conn = new URL(url).openConnection().asInstanceOf[HttpURLConnection]
+      conn.setInstanceFollowRedirects(true)
+      conn.setConnectTimeout(15000)
+      conn.setReadTimeout(60000)
+      conn.setRequestMethod("GET")
+
+      var in: InputStream = null
+      var zis: ZipInputStream = null
+      try {
+        in = new BufferedInputStream(conn.getInputStream)
+        zis = new ZipInputStream(in)
+
+        var entry: ZipEntry = zis.getNextEntry
+        val buffer = new Array[Byte](8192)
+
+        while (entry != null) {
+          val target = dest.resolve(entry.getName).normalize()
+          if (entry.isDirectory) Files.createDirectories(target)
+          else {
+            Files.createDirectories(target.getParent)
+            var out: OutputStream = null
+            try {
+              out = new BufferedOutputStream(Files.newOutputStream(target, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING))
+              var n = zis.read(buffer)
+              while (n != -1) {
+                out.write(buffer, 0, n)
+                n = zis.read(buffer)
+              }
+            } finally if (out != null) out.close()
+          }
+
+          zis.closeEntry()
+          entry = zis.getNextEntry
+        }
+      } finally {
+        if (zis != null) zis.close()
+        if (in != null) in.close()
+        conn.disconnect()
+      }
+    }
+
+    import collection.JavaConverters._
+    Files.walk(dest)
+        .filter(p => p.toString().endsWith(".scala"))
+        .map[java.io.File] { (file: java.nio.file.Path) =>
+          val text = new String(Files.readAllBytes(file.path), java.nio.charset.StandardCharsets.UTF_8)
+          if (!file.getFileName().toString().equals("CollectionName.scala")) Files.write(
+            file,
+            ("package dotty.shaded\n" +
+              text
+                .replace("import scala", "import _root_.scala")
+                .replace(" scala.collection.", " _root_.scala.collection.")
+                .replace("_root_.pprint", "_root_.dotty.shaded.pprint")
+                .replace("_root_.fansi", "_root_.dotty.shaded.fansi")
+                .replace("def apply(c: Char): Trie[T]", "def apply(c: Char): Trie[T] | Null")
+                .replace("var head: Iterator[T] = null", "var head: Iterator[T] | Null = null")
+                .replace("if (head != null && head.hasNext) true", "if (head != null && head.nn.hasNext) true")
+                .replace("head.next()", "head.nn.next()")
+                .replace("abstract class Walker", "@scala.annotation.nowarn abstract class Walker")
+                .replace("object TPrintLowPri", "@scala.annotation.nowarn object TPrintLowPri")).getBytes
+          )
+          file.toFile
+
+        }
+        .collect(java.util.stream.Collectors.toList()).asScala.toSeq
+
+  }.taskValue
   // Settings shared between scala3-compiler and scala3-compiler-bootstrapped
   lazy val commonDottyCompilerSettings = Seq(
       // Note: bench/profiles/projects.yml should be updated accordingly.
@@ -721,6 +809,8 @@ object Build {
         ("io.get-coursier" %% "coursier" % "2.0.16" % Test).cross(CrossVersion.for3Use2_13),
       ),
 
+      shadedSourceGenerator,
+
       // For convenience, change the baseDirectory when running the compiler
       Compile / forkOptions := (Compile / forkOptions).value.withWorkingDirectory((ThisBuild / baseDirectory).value),
       Compile / run / forkOptions := (Compile / run / forkOptions).value.withWorkingDirectory((ThisBuild / baseDirectory).value),
@@ -2141,6 +2231,7 @@ object Build {
 
         Seq(file)
       }.taskValue,
+      shadedSourceGenerator,
       // sbt adds all the projects to scala-tool config which breaks building the scalaInstance
       // as a workaround, I build it manually by only adding the compiler
       scalaInstance := {
@@ -2330,6 +2421,7 @@ object Build {
           sjsSources
         } (Set(scalaJSIRSourcesJar)).toSeq
       }.taskValue,
+      shadedSourceGenerator
     )
 
   // ==============================================================================================

staging/test-resources/repl-staging/i6007

@@ -5,6 +5,6 @@ def compiler: scala.quoted.staging.Compiler
 scala> def v(using Quotes) = '{ (if true then Some(1) else None).map(v => v+1) }
 def v(using x$1: scala.quoted.Quotes): scala.quoted.Expr[Option[Int]]
 scala> scala.quoted.staging.withQuotes(v.show)
-val res0: String = (if (true) scala.Some.apply[scala.Int](1) else scala.None).map[scala.Int](((v: scala.Int) => v.+(1)))
+val res0: String = "(if (true) scala.Some.apply[scala.Int](1) else scala.None).map[scala.Int](((v: scala.Int) => v.+(1)))"
 scala> scala.quoted.staging.run(v)
 val res1: Option[Int] = Some(2)