From 116c1e1e8b9386facef645161f398f91c1967e18 Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Sun, 26 Apr 2015 17:05:20 +0100
Subject: [PATCH] Fix crossScalaVersions default, derived from scalaVersion.

Fixes #1828.
---
 main/src/main/scala/sbt/Defaults.scala               |  2 +-
 notes/0.13.9/cross-scala-versions-default.markdown   | 12 ++++++++++++
 .../project/cross-scala-versions-default/build.sbt   |  6 ++++++
 .../project/cross-scala-versions-default/test        |  1 +
 4 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 notes/0.13.9/cross-scala-versions-default.markdown
 create mode 100644 sbt/src/sbt-test/project/cross-scala-versions-default/build.sbt
 create mode 100644 sbt/src/sbt-test/project/cross-scala-versions-default/test

diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index 5dc348471..190b35b5a 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -238,7 +238,7 @@ object Defaults extends BuildCommon {
     javacOptions :== Nil,
     scalacOptions :== Nil,
     scalaVersion := appConfiguration.value.provider.scalaProvider.version,
-    crossScalaVersions := Seq(scalaVersion.value),
+    derive(crossScalaVersions := Seq(scalaVersion.value)),
     derive(compilersSetting),
     derive(scalaBinaryVersion := binaryScalaVersion(scalaVersion.value))
   ))
diff --git a/notes/0.13.9/cross-scala-versions-default.markdown b/notes/0.13.9/cross-scala-versions-default.markdown
new file mode 100644
index 000000000..2bded7c1e
--- /dev/null
+++ b/notes/0.13.9/cross-scala-versions-default.markdown
@@ -0,0 +1,12 @@
+
+  [@dwijnand]: http://github.com/dwijnand
+  [1828]: https://github.com/sbt/sbt/issues/1828
+  [1922]: https://github.com/sbt/sbt/pull/1992
+
+### Fixes with compatibility implications
+
+### Improvements
+
+### Bug fixes
+
+- Fix `crossScalaVersions` default, now correctly derives from the configured `scalaVersion`. [#1828][1828]/[#1992][1992] by [@dwijnand][@dwijnand]
diff --git a/sbt/src/sbt-test/project/cross-scala-versions-default/build.sbt b/sbt/src/sbt-test/project/cross-scala-versions-default/build.sbt
new file mode 100644
index 000000000..f791d581e
--- /dev/null
+++ b/sbt/src/sbt-test/project/cross-scala-versions-default/build.sbt
@@ -0,0 +1,6 @@
+scalaVersion := "2.11.6"
+
+TaskKey[Unit]("check") := {
+  assert(crossScalaVersions.value == Seq("2.11.6"),
+    s"""crossScalaVersions should be Seq("2.11.6") but is ${crossScalaVersions.value}""")
+}
diff --git a/sbt/src/sbt-test/project/cross-scala-versions-default/test b/sbt/src/sbt-test/project/cross-scala-versions-default/test
new file mode 100644
index 000000000..15675b169
--- /dev/null
+++ b/sbt/src/sbt-test/project/cross-scala-versions-default/test
@@ -0,0 +1 @@
+> check