Add extra info in unqualified getClass warning

Author: nicolasstucki

compiler/src/dotty/tools/dotc/reporting/messages.scala

@@ -2415,9 +2415,14 @@ class UnqualifiedCallToAnyRefMethod(stat: untpd.Tree, method: Symbol)(using Cont
  def kind = MessageKind.PotentialIssue
  def msg(using Context) = i"Suspicious top-level unqualified call to ${hl(method.name.toString)}"
  def explain(using Context) =
+ val getClassExtraHint =
+ if method.name == nme.getClass_ && ctx.settings.classpath.value.contains("scala3-staging") then
+ i"""\n\n
+ |This class should not be used to get the classloader for `scala.quoted.staging.Compile.make`."""
+ else ""
  i"""Top-level unqualified calls to ${hl("AnyRef")} or ${hl("Any")} methods such as ${hl(method.name.toString)} are
  |resolved to calls on ${hl("Predef")} or on imported methods. This might not be what
- |you intended."""
+ |you intended.$getClassExtraHint"""
 }
 
 class SynchronizedCallOnBoxedClass(stat: tpd.Tree)(using Context)