From 7f112052bfe8de2b8b53399449af11ca51c5395e Mon Sep 17 00:00:00 2001
From: Ethan Atkins <contact@ethanatkins.com>
Date: Wed, 21 Aug 2019 00:02:43 -0700
Subject: [PATCH] Unbreak binary compatibility

We discovered in the community build that 1.3.0-RC4 breaks the
lucidchart scalafmt plugins. We can unbreak binary compatibility by
adding alternative classes.
---
 build.sbt                                     |  9 -----
 .../src/main/scala/sbt/util/FileInfo.scala    | 35 ++++++++++++++-----
 2 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/build.sbt b/build.sbt
index c807ce0fe..64621fdcd 100644
--- a/build.sbt
+++ b/build.sbt
@@ -152,15 +152,6 @@ lazy val utilCache = (project in file("util-cache"))
     libraryDependencies ++= Seq(scalaTest),
     mimaSettings,
     mimaBinaryIssueFilters ++= Seq(
-      // These are private case classes that have changed
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHashModified.apply"),
-      exclude[IncompatibleResultTypeProblem]("sbt.util.FileHashModified.copy$default$2"),
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHashModified.copy"),
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHashModified.this"),
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHash.apply"),
-      exclude[IncompatibleResultTypeProblem]("sbt.util.FileHash.copy$default$2"),
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHash.copy"),
-      exclude[IncompatibleMethTypeProblem]("sbt.util.FileHash.this"),
       // Added a method to a sealed trait, technically not a problem for Scala
       exclude[ReversedMissingMethodProblem]("sbt.util.HashFileInfo.hashArray"),
     )
diff --git a/util-cache/src/main/scala/sbt/util/FileInfo.scala b/util-cache/src/main/scala/sbt/util/FileInfo.scala
index b31640b02..d994d77cf 100644
--- a/util-cache/src/main/scala/sbt/util/FileInfo.scala
+++ b/util-cache/src/main/scala/sbt/util/FileInfo.scala
@@ -36,9 +36,25 @@ object HashModifiedFileInfo {
 
 private final case class PlainFile(file: File, exists: Boolean) extends PlainFileInfo
 private final case class FileModified(file: File, lastModified: Long) extends ModifiedFileInfo
-private final case class FileHash(file: File, hashArray: Array[Byte]) extends HashFileInfo
-private final case class FileHashModified(file: File, hashArray: Array[Byte], lastModified: Long)
-    extends HashModifiedFileInfo
+@deprecated("Kept for plugin compat, but will be removed in sbt 2.0", "1.3.0")
+private final case class FileHash(file: File, override val hash: List[Byte]) extends HashFileInfo {
+  override val hashArray: Array[Byte] = hash.toArray
+}
+private final case class FileHashArrayRepr(file: File, override val hashArray: Array[Byte])
+    extends HashFileInfo
+@deprecated("Kept for plugin compat, but will be removed in sbt 2.0", "1.3.0")
+private final case class FileHashModified(
+    file: File,
+    override val hash: List[Byte],
+    lastModified: Long
+) extends HashModifiedFileInfo {
+  override val hashArray: Array[Byte] = hash.toArray
+}
+private final case class FileHashModifiedArrayRepr(
+    file: File,
+    override val hashArray: Array[Byte],
+    lastModified: Long
+) extends HashModifiedFileInfo
 
 final case class FilesInfo[F <: FileInfo] private (files: Set[F])
 object FilesInfo {
@@ -111,15 +127,15 @@ object FileInfo {
           val hash = unbuilder.readField[Array[Byte]]("hash")
           val lastModified = unbuilder.readField[Long]("lastModified")
           unbuilder.endObject()
-          FileHashModified(file, hash, lastModified)
+          FileHashModifiedArrayRepr(file, hash, lastModified)
         case None => deserializationError("Expected JsObject but found None")
       }
     }
 
     implicit def apply(file: File): HashModifiedFileInfo =
-      FileHashModified(file.getAbsoluteFile, Hash(file), IO.getModifiedTimeOrZero(file))
+      FileHashModifiedArrayRepr(file.getAbsoluteFile, Hash(file), IO.getModifiedTimeOrZero(file))
     def apply(file: File, hash: Array[Byte], lastModified: Long): HashModifiedFileInfo =
-      FileHashModified(file.getAbsoluteFile, hash, lastModified)
+      FileHashModifiedArrayRepr(file.getAbsoluteFile, hash, lastModified)
   }
 
   object hash extends Style {
@@ -139,14 +155,15 @@ object FileInfo {
           val file = unbuilder.readField[File]("file")
           val hash = unbuilder.readField[Array[Byte]]("hash")
           unbuilder.endObject()
-          FileHash(file, hash)
+          FileHashArrayRepr(file, hash)
         case None => deserializationError("Expected JsObject but found None")
       }
     }
 
-    implicit def apply(file: File): HashFileInfo = FileHash(file.getAbsoluteFile, computeHash(file))
+    implicit def apply(file: File): HashFileInfo =
+      FileHashArrayRepr(file.getAbsoluteFile, computeHash(file))
     def apply(file: File, bytes: Array[Byte]): HashFileInfo =
-      FileHash(file.getAbsoluteFile, bytes)
+      FileHashArrayRepr(file.getAbsoluteFile, bytes)
 
     private def computeHash(file: File): Array[Byte] =
       try Hash(file)