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- Test major TASTy version
- strip margins of `s".."`
- Cache `CompilationUnit` in `SymbolLoaders`

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala

@@ -422,7 +422,7 @@ class TastyLoader(val tastyFile: AbstractFile) extends SymbolLoader {
       val tastyBytes = tastyFile.toByteArray
       new tasty.DottyUnpickler(tastyBytes) // reads header and name table
 
-  def compilationUnitInfo: CompilationUnitInfo | Null =
+  val compilationUnitInfo: CompilationUnitInfo | Null =
     val tastyHeader = unpickler.unpickler.header
     val tastyVersion = TastyVersion(
       tastyHeader.majorVersion,
@@ -453,10 +453,10 @@ class TastyLoader(val tastyFile: AbstractFile) extends SymbolLoader {
       val message = e match
         case e: UnpickleException =>
           s"""TASTy file ${tastyFile.canonicalPath} could not be read, failing with:
-            |  ${Option(e.getMessage).getOrElse("")}"""
+            |  ${Option(e.getMessage).getOrElse("")}""".stripMargin
         case _ =>
           s"""TASTy file ${tastyFile.canonicalPath} is broken, reading aborted with ${e.getClass}
-            |  ${Option(e.getMessage).getOrElse("")}"""
+            |  ${Option(e.getMessage).getOrElse("")}""".stripMargin
       throw IOException(message, e)
 
 

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

@@ -1073,7 +1073,7 @@ trait Checking {
       case id @ Ident(name: Name) =>
         def methCompiledBeforeDeprecation =
           meth.tastyVersion match
-            case Some(version) => version.minor < 4 // compiled before 3.4
+            case Some(version) => version.major == 28 && version.minor < 4 // compiled before 3.4
             case _ => false // compiled with the current compiler
         name.toTermName match {
           case name: SimpleName