invalidate by external improvements

Author: lukaszwawrzyk

internal/zinc-core/src/main/scala/sbt/internal/inc/IncrementalNameHashing.scala

@@ -68,7 +68,7 @@ private final class IncrementalNameHashing(log: sbt.util.Logger, options: IncOpt
                                               externalAPIChange: APIChange,
                                               isScalaClass: String => Boolean): Set[String] = {
     val modifiedBinaryClassName = externalAPIChange.modifiedClass
-    val invalidationReason = memberRefInvalidator.invalidationReason(externalAPIChange)
+    val invalidationReason = memberRefInvalidator.invalidationReason(externalAPIChange).capitalize
     log.debug(
       s"$invalidationReason\nAll member reference dependencies will be considered within this context.")
     // Propagate inheritance dependencies transitively.
@@ -136,20 +136,17 @@ private final class IncrementalNameHashing(log: sbt.util.Logger, options: IncOpt
     def debugMessage: String = {
       if (all.isEmpty) s"Change $change does not affect any class."
       else {
-        val byTransitiveInheritance =
-          if (transitiveInheritance.nonEmpty) s"by transitive inheritance: $transitiveInheritance"
-          else ""
-        val byLocalInheritance =
-          if (localInheritance.nonEmpty) s"by local inheritance: $localInheritance" else ""
-        val byMemberRef =
-          if (memberRef.nonEmpty) s"by member reference: $memberRef" else ""
-
-        s"""Change $change invalidates ${all.size} classes due to ${memberRefInvalidator
-             .invalidationReason(change)}
-           |\t> $byTransitiveInheritance
-           |\t> $byLocalInheritance
-           |\t> $byMemberRef
-        """.stripMargin
+        def by(reason: String, classes: Set[String]) = {
+          if (classes.isEmpty) ""
+          else {
+            s"\tby $reason: ${classes.mkString(", ")}\n"
+          }
+        }
+
+        s"${all.size} classes were invalidated due to ${memberRefInvalidator.invalidationReason(change)}\n" +
+          by("transitive inheritance", transitiveInheritance) +
+          by("local inheritance", localInheritance) +
+          by("member reference", memberRef)
       }
     }
 

internal/zinc-core/src/main/scala/sbt/internal/inc/MemberRefInvalidator.scala

@@ -67,17 +67,15 @@ private[inc] class MemberRefInvalidator(log: Logger, logRecompileOnMacro: Boolea
 
   def invalidationReason(apiChange: APIChange): String = apiChange match {
     case TraitPrivateMembersModified(modifiedClass) =>
-      s"The private signature of trait ${modifiedClass} changed."
+      s"the private signature of trait $modifiedClass changed."
     case APIChangeDueToMacroDefinition(modifiedSrcFile) =>
-      s"The $modifiedSrcFile source file declares a macro."
+      s"the $modifiedSrcFile source file declares a macro."
     case NamesChange(modifiedClass, modifiedNames) =>
       modifiedNames.in(UseScope.Implicit) match {
         case changedImplicits if changedImplicits.isEmpty =>
-          s"""|The $modifiedClass has the following regular definitions changed:
-              |\t${modifiedNames.names.mkString(", ")}.""".stripMargin
+          s"the $modifiedClass has the following regular definitions changed: ${modifiedNames.names}"
         case changedImplicits =>
-          s"""|The $modifiedClass has the following implicit definitions changed:
-              |\t${changedImplicits.mkString(", ")}.""".stripMargin
+          s"""the $modifiedClass has the following implicit definitions changed: $changedImplicits""".stripMargin
       }
   }