Fix #9227: Do not suspend REPL compilation unit

compiler/src/dotty/tools/dotc/CompilationUnit.scala

@@ -14,6 +14,7 @@ import typer.Nullables
 import transform.SymUtils._
 import core.Decorators.{given _}
 import config.SourceVersion
+import StdNames.str
 
 class CompilationUnit protected (val source: SourceFile) {
 
@@ -23,8 +24,12 @@ class CompilationUnit protected (val source: SourceFile) {
 
   var tpdTree: tpd.Tree = tpd.EmptyTree
 
+  /** Is this the compilation unit of a Java file */
   def isJava: Boolean = source.file.name.endsWith(".java")
 
+  /** Is this the compilation unit of a REPL input */
+  def isREPL: Boolean = source.file.name.startsWith(str.REPL_SESSION_LINE)
+
   /** The source version for this unit, as determined by a language import */
   var sourceVersion: Option[SourceVersion] = None
 
@@ -47,7 +52,14 @@ class CompilationUnit protected (val source: SourceFile) {
 
   var suspended: Boolean = false
 
+  /** Can this compilation unit be suspended */
+  def isSuspendable: Boolean = !isREPL
+
+  /** Suspends the compilation unit by thowing a SuspendException
+   *  and recoring the suspended compilation unit
+   */
   def suspend()(using Context): Nothing =
+    assert(isSuspendable)
     if !suspended then
       if (ctx.settings.XprintSuspension.value)
         ctx.echo(i"suspended: $this")

compiler/src/dotty/tools/dotc/transform/Splicer.scala

@@ -393,7 +393,7 @@ object Splicer {
           ex.getTargetException match {
             case ex: scala.quoted.Reporting.StopQuotedContext =>
               throw ex
-            case MissingClassDefinedInCurrentRun(sym) =>
+            case MissingClassDefinedInCurrentRun(sym) if ctx.compilationUnit.isSuspendable =>
               if (ctx.settings.XprintSuspension.value)
                 ctx.echo(i"suspension triggered by a dependency on $sym", pos)
               ctx.compilationUnit.suspend() // this throws a SuspendException

compiler/src/dotty/tools/dotc/typer/Inliner.scala

@@ -1407,14 +1407,15 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(using Context) {
     assert(level == 0)
     val inlinedFrom = enclosingInlineds.last
     val dependencies = macroDependencies(body)
-
+    val suspendable = ctx.compilationUnit.isSuspendable
     if dependencies.nonEmpty && !ctx.reporter.errorsReported then
       for sym <- dependencies do
         if ctx.compilationUnit.source.file == sym.associatedFile then
           ctx.error(em"Cannot call macro $sym defined in the same source file", call.sourcePos)
-        if (ctx.settings.XprintSuspension.value)
+        if (suspendable && ctx.settings.XprintSuspension.value)
           ctx.echo(i"suspension triggered by macro call to ${sym.showLocated} in ${sym.associatedFile}", call.sourcePos)
-      ctx.compilationUnit.suspend() // this throws a SuspendException
+      if suspendable then
+        ctx.compilationUnit.suspend() // this throws a SuspendException
 
     val evaluatedSplice = inContext(tastyreflect.MacroExpansion.context(inlinedFrom)) {
       Splicer.splice(body, inlinedFrom.sourcePos, MacroClassLoader.fromContext)

compiler/test-resources/repl/i9227

@@ -0,0 +1,5 @@
+scala> import scala.quoted._; inline def myMacro[T]: Unit = ${ myMacroImpl[T] }; def myMacroImpl[T](using qctx: QuoteContext): Expr[Unit] = '{}; println(myMacro[Int])
+1 | import scala.quoted._; inline def myMacro[T]: Unit = ${ myMacroImpl[T] }; def myMacroImpl[T](using qctx: QuoteContext): Expr[Unit] = '{}; println(myMacro[Int])
+  |                                                                                                                                                   ^^^^^^^^^^^^
+  |      Cannot call macro method myMacroImpl defined in the same source file
+  | This location contains code that was inlined from rs$line$1:1