Better message on TASTY mismatch

romanowski · May 3, 2023 · 9247813 · 9247813
1 parent b8d2966
commit 9247813
Showing 1 changed file with 13 additions and 5 deletions.
diff --git a/tasty/src/dotty/tools/tasty/TastyHeaderUnpickler.scala b/tasty/src/dotty/tools/tasty/TastyHeaderUnpickler.scala
@@ -107,11 +107,19 @@ object TastyHeaderUnpickler {
     }
     val minorVersion = showMinorVersion(MinorVersion, ExperimentalVersion)
     val fileMinorVersion = showMinorVersion(fileMinor, fileExperimental)
-    s"""TASTy signature has wrong version.
-      | expected: {majorVersion: $MajorVersion, minorVersion: $minorVersion}
-      | found   : {majorVersion: $fileMajor, minorVersion: $fileMinorVersion}
-      |
-      |""".stripMargin
+
+    if (MinorVersion == 28 && fileMinorVersion == "25")
+      s"""Code in compiled newer minor version of Scala: 3.$fileExperimental, expected version 3.$minorVersion or older}
+         |This indicate that classpath is misconfigured.
+         |Updating Scala compiler verion to 3.$minorVersion.x may also solve the problem.""".stripMargin
+    else
+        s"""TASTy signature has wrong version.
+           | expected: {majorVersion: $MajorVersion, minorVersion: $minorVersion}
+           | found   : {majorVersion: $fileMajor, minorVersion: $fileMinorVersion}
+           |
+           |Unable to map found TASTY versions into a Scala versions.
+           |""".stripMargin
+
   }
 
   private def unstableAddendum =