Reuse the same compiler instance for all tests in a JUnit class

Note that JUnit creates a new instance of the test class for running
each test method. So the compiler instance is added to the companion.
However, the JVM would quickly run out of memory when running multiple
tests, as the compilers cannot be GCd. So we make it a `var`, and set
it to null when a class is done. For that we use JUnit's `@AfterClass`
which is required to be on a static method. Therefore we add a Java
class with such a static method that we can extend from Scala.

1 files changed, 9 insertions, 0 deletions

diff --git a/build.xml b/build.xml
index 5f6b04b8e4..ee6a045bda 100755
--- a/build.xml
+++ b/build.xml
@@ -1448,6 +1448,15 @@ TODO:
   <target name="test.junit.comp" depends="pack.done">
     <stopwatch name="test.junit.compiler.timer"/>
     <mkdir dir="${test.junit.classes}"/>
+    <javac
+      debug="true"
+      srcdir="${test.junit.src}"
+      destdir="${test.junit.classes}"
+      classpathref="test.junit.compiler.build.path"
+      target="1.6"
+      source="1.5"
+      compiler="javac1.6"
+      includes="**/*.java"/>
     <scalacfork
       destdir="${test.junit.classes}"
       compilerpathref="quick.compiler.path"