Merge pull request #3778 from xeno-by/topic/plugins-is-blackbox

adds MacroPlugin.pluginsIsBlackbox

2 files changed, 24 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/AnalyzerPlugins.scala b/src/compiler/scala/tools/nsc/typechecker/AnalyzerPlugins.scala
index fa6e5399eb..5a70d4c524 100644
--- a/src/compiler/scala/tools/nsc/typechecker/AnalyzerPlugins.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/AnalyzerPlugins.scala
@@ -190,6 +190,16 @@ trait AnalyzerPlugins { self: Analyzer =>
     def pluginsTypedMacroBody(typer: Typer, ddef: DefDef): Option[Tree] = None
 
     /**
+     * Figures out whether the given macro definition is blackbox or whitebox.
+     *
+     * Default implementation provided in `self.standardIsBlackbox` loads the macro impl binding
+     * and fetches boxity from the "isBlackbox" field of the macro signature.
+     *
+     * $nonCumulativeReturnValueDoc.
+     */
+    def pluginsIsBlackbox(macroDef: Symbol): Option[Boolean] = None
+
+    /**
      * Expands an application of a def macro (i.e. of a symbol that has the MACRO flag set),
      * possibly using the current typer mode and the provided prototype.
      *
@@ -375,6 +385,14 @@ trait AnalyzerPlugins { self: Analyzer =>
     def custom(plugin: MacroPlugin) = plugin.pluginsTypedMacroBody(typer, ddef)
   })
 
+  /** @see MacroPlugin.pluginsIsBlackbox */
+  def pluginsIsBlackbox(macroDef: Symbol): Boolean = invoke(new NonCumulativeOp[Boolean] {
+    def position = macroDef.pos
+    def description = "compute boxity for this macro definition"
+    def default = standardIsBlackbox(macroDef)
+    def custom(plugin: MacroPlugin) = plugin.pluginsIsBlackbox(macroDef)
+  })
+
   /** @see MacroPlugin.pluginsMacroExpand */
   def pluginsMacroExpand(typer: Typer, expandee: Tree, mode: Mode, pt: Type): Tree = invoke(new NonCumulativeOp[Tree] {
     def position = expandee.pos
diff --git a/src/compiler/scala/tools/nsc/typechecker/Macros.scala b/src/compiler/scala/tools/nsc/typechecker/Macros.scala
index f40a92f8e5..ef74beec62 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Macros.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Macros.scala
@@ -263,7 +263,12 @@ trait Macros extends MacroRuntimes with Traces with Helpers {
     }
 
   def isBlackbox(expandee: Tree): Boolean = isBlackbox(dissectApplied(expandee).core.symbol)
-  def isBlackbox(macroDef: Symbol): Boolean = {
+  def isBlackbox(macroDef: Symbol): Boolean = pluginsIsBlackbox(macroDef)
+
+  /** Default implementation of `isBlackbox`.
+   *  Can be overridden by analyzer plugins (see AnalyzerPlugins.pluginsIsBlackbox for more details)
+   */
+  def standardIsBlackbox(macroDef: Symbol): Boolean = {
     val fastTrackBoxity = fastTrack.get(macroDef).map(_.isBlackbox)
     val bindingBoxity = loadMacroImplBinding(macroDef).map(_.isBlackbox)
     fastTrackBoxity orElse bindingBoxity getOrElse false