Store buildcharacter.properties in scala-compiler.jar

In addition to all the individual projects’ version properties files
that we already keep in `scala-compiler.jar` we now write a new
`scala-buildcharacter.properties` which is identical to the
`buildcharacter.properties` written to the root directory by
`generateBuildCharacterPropertiesFile`. The new task
`extractBuildCharacterPropertiesFile` extracts it from the bootstrap
Scala compiler and writes the usual `buildcharacter.properties`.

This can be used to reproduce the exact version information for all
modules in builds that start from an arbitrary published Scala version
instead of being triggered directly by a bootstrap job.

1 files changed, 6 insertions, 3 deletions

diff --git a/project/VersionUtil.scala b/project/VersionUtil.scala
index 1c2fff27b7..fde55a5969 100644
--- a/project/VersionUtil.scala
+++ b/project/VersionUtil.scala
@@ -8,8 +8,10 @@ import BuildSettings.autoImport._
 object VersionUtil {
   lazy val copyrightString = settingKey[String]("Copyright string.")
   lazy val versionProperties = settingKey[Versions]("Version properties.")
-  lazy val generateVersionPropertiesFile = taskKey[File]("Generating version properties file.")
-  lazy val generateBuildCharacterPropertiesFile = taskKey[File]("Generating buildcharacter.properties file.")
+  lazy val buildCharacterPropertiesFile = settingKey[File]("The file which gets generated by generateBuildCharacterPropertiesFile")
+  lazy val generateVersionPropertiesFile = taskKey[File]("Generate version properties file.")
+  lazy val generateBuildCharacterPropertiesFile = taskKey[File]("Generate buildcharacter.properties file.")
+  lazy val extractBuildCharacterPropertiesFile = taskKey[File]("Extract buildcharacter.properties file from bootstrap scala-compiler.")
 
   lazy val globalVersionSettings = Seq[Setting[_]](
     // Set the version properties globally (they are the same for all projects)
@@ -24,6 +26,7 @@ object VersionUtil {
   )
 
   lazy val generateBuildCharacterFileSettings = Seq[Setting[_]](
+    buildCharacterPropertiesFile := ((baseDirectory in ThisBuild).value / "buildcharacter.properties"),
     generateBuildCharacterPropertiesFile := generateBuildCharacterPropertiesFileImpl.value
   )
 
@@ -101,7 +104,7 @@ object VersionUtil {
     writeProps(v.toMap ++ versionProps ++ Map(
       "maven.version.base" -> v.mavenBase,
       "maven.version.suffix" -> v.mavenSuffix
-    ), (baseDirectory in ThisBuild).value / "buildcharacter.properties")
+    ), buildCharacterPropertiesFile.value)
   }
 
   private def writeProps(m: Map[String, String], propFile: File): File = {