Merge pull request #2941 from huitseeker/less-destructive-docComments-reset

Cautiously give PC more control over docComments table

3 files changed, 27 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/ast/DocComments.scala b/src/compiler/scala/tools/nsc/ast/DocComments.scala
index f2e5c9b1eb..7cf2f8559b 100755
--- a/src/compiler/scala/tools/nsc/ast/DocComments.scala
+++ b/src/compiler/scala/tools/nsc/ast/DocComments.scala
@@ -18,8 +18,14 @@ trait DocComments { self: Global =>
 
   val cookedDocComments = mutable.HashMap[Symbol, String]()
 
-  /** The raw doc comment map */
-  val docComments = mutable.HashMap[Symbol, DocComment]()
+  /** The raw doc comment map
+   *
+   * In IDE, background compilation runs get interrupted by
+   * reloading new sourcefiles. This is weak to avoid
+   * memleaks due to the doc of their cached symbols
+   * (e.g. in baseTypeSeq) between periodic doc reloads.
+   */
+  val docComments = mutable.WeakHashMap[Symbol, DocComment]()
 
   def clearDocComments() {
     cookedDocComments.clear()
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 55268b1e1a..5c8f1bd1c7 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -43,12 +43,17 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper
 
   final val shortenImports = false
 
+  // allows override of the behavior of the resetTyper method w.r.t comments
+  def resetDocComments() = {
+    clearDocComments()
+  }
+
   def resetTyper() {
     //println("resetTyper called")
     resetContexts()
     resetImplicits()
     transformed.clear()
-    clearDocComments()
+    resetDocComments()
   }
 
   object UnTyper extends Traverser {
diff --git a/src/interactive/scala/tools/nsc/interactive/Global.scala b/src/interactive/scala/tools/nsc/interactive/Global.scala
index bc6df9eb25..736a1e68c4 100644
--- a/src/interactive/scala/tools/nsc/interactive/Global.scala
+++ b/src/interactive/scala/tools/nsc/interactive/Global.scala
@@ -18,6 +18,19 @@ import scala.tools.nsc.typechecker.Analyzer
 import symtab.Flags.{ACCESSOR, PARAMACCESSOR}
 import scala.annotation.{ elidable, tailrec }
 import scala.language.implicitConversions
+import scala.tools.nsc.typechecker.Typers
+
+/**
+ * This trait allows the IDE to have an instance of the PC that
+ * does not clear the comments table at every new typer run (those
+ * being many and close between in this context).
+ */
+
+trait CommentPreservingTypers extends Typers {
+  self: Analyzer =>
+
+  override def resetDocComments() = {}
+}
 
 trait InteractiveScaladocAnalyzer extends InteractiveAnalyzer with ScaladocAnalyzer {
   val global : Global