Merge remote-tracking branch 'cancel-bug' into 0.13

compile/inc/src/main/scala/sbt/inc/Compile.scala

@@ -22,7 +22,15 @@ object IncrementalCompile
 		val current = Stamps.initial(Stamp.exists, Stamp.hash, Stamp.lastModified)
 		val internalMap = (f: File) => previous.relations.produced(f).headOption
 		val externalAPI = getExternalAPI(entry, forEntry)
-		Incremental.compile(sources, entry, previous, current, forEntry, doCompile(compile, internalMap, externalAPI, current, output, options), log, options)
+		try {
+			Incremental.compile(sources, entry, previous, current, forEntry, doCompile(compile, internalMap, externalAPI, current, output, options), log, options)
+		} catch {
+			case e: xsbti.CompileCancelled =>
+				log.info("Compilation has been cancelled")
+				// in case compilation got cancelled potential partial compilation results (e.g. produced classs files) got rolled back
+				// and we can report back as there was no change (false) and return a previous Analysis which is still up-to-date
+				(false, previous)
+		}
 	}
 	def doCompile(compile: (Set[File], DependencyChanges, xsbti.AnalysisCallback) => Unit, internalMap: File => Option[File], externalAPI: (File, String) => Option[Source], current: ReadStamps, output: Output, options: IncOptions) =
 	  (srcs: Set[File], changes: DependencyChanges) => {

compile/interface/src/main/scala/xsbt/CompilerInterface.scala

@@ -50,6 +50,8 @@ sealed abstract class CallbackGlobal(settings: Settings, reporter: reporters.Rep
 }
 class InterfaceCompileFailed(val arguments: Array[String], val problems: Array[Problem], override val toString: String) extends xsbti.CompileFailed
 
+class InterfaceCompileCancelled(val arguments: Array[String], override val toString: String) extends xsbti.CompileCancelled
+
 private final class WeakLog(private[this] var log: Logger, private[this] var delegate: Reporter)
 {
 	def apply(message: String) {
@@ -124,12 +126,21 @@ private final class CachedCompiler0(args: Array[String], output: Output, initial
 		}
 		dreporter.printSummary()
 		if(!noErrors(dreporter)) handleErrors(dreporter, log)
+		// the case where we cancelled compilation _after_ some compilation errors got reported
+		// will be handled by line above so errors still will be reported properly just potentially not
+		// all of them (because we cancelled the compilation)
+		if (dreporter.cancelled) handleCompilationCancellation(dreporter, log)
 	}
 	def handleErrors(dreporter: DelegatingReporter, log: Logger): Nothing =
 	{
 		debug(log, "Compilation failed (CompilerInterface)")
 		throw new InterfaceCompileFailed(args, dreporter.problems, "Compilation failed")
 	}
+	def handleCompilationCancellation(dreporter: DelegatingReporter, log: Logger): Nothing = {
+		assert(dreporter.cancelled, "We should get here only if when compilation got cancelled")
+		debug(log, "Compilation cancelled (CompilerInterface)")
+		throw new InterfaceCompileCancelled(args, "Compilation has been cancelled")
+	}
 	def processUnreportedWarnings(run: compiler.Run)
 	{
 			// allConditionalWarnings and the ConditionalWarning class are only in 2.10+

interface/src/main/java/xsbti/CompileCancelled.java

@@ -0,0 +1,9 @@
+package xsbti;
+
+/**
+ * An exception thrown when compilation cancellation has been requested during
+ * Scala compiler run.
+ */
+public abstract class CompileCancelled extends RuntimeException {
+	public abstract String[] arguments();
+}