Added coverage aggregator

Author: sksamuel

scalac-scoverage-plugin/src/main/scala/scoverage/IOUtils.scala

@@ -64,20 +64,7 @@ object IOUtils {
     search(baseDir)
   }
 
-  /**
-   * Aggregates all subproject reports, returning the location of the aggregated file.
-   */
-  val aggregator: (File, File) => Unit = (baseDir, targetDir) => {
-    val files = IOUtils.reportFileSearch(baseDir)
-    println(s"[info] Found ${files.size} subproject report files [${files.mkString(",")}]")
-    if (files.size > 0) {
-      val nodes = files.map(xml.XML.loadFile)
-      val aggregated = ScoverageXmlMerger.merge(nodes)
-      targetDir.mkdirs()
-      val outFile = new File(targetDir, Constants.XMLReportFilename)
-      writeToFile(outFile, aggregated.toString)
-    }
-  }
+
 
   val isMeasurementFile = (file: File) => file.getName.startsWith(Constants.MeasurementsPrefix)
   val isReportFile = (file: File) => file.getName == Constants.XMLReportFilename

scalac-scoverage-plugin/src/main/scala/scoverage/report/CoverageAggregator.scala

@@ -0,0 +1,32 @@
+package scoverage.report
+
+import java.io.File
+
+import scoverage.{Coverage, IOUtils}
+
+object CoverageAggregator {
+
+  def aggregate(baseDir: File, targetDir: File): Option[Coverage] = {
+    val files = IOUtils.reportFileSearch(baseDir)
+    println(s"[info] Found ${files.size} subproject report files [${files.mkString(",")}]")
+    if (files.size > 0) {
+      val coverage = aggregatedCoverage(files)
+      Some(coverage)
+    } else {
+      None
+    }
+  }
+
+  private def aggregatedCoverage(files: Seq[File]): Coverage = {
+    var id = 0
+    val coverage = Coverage()
+    files foreach {
+      case file =>
+        val subcoverage = ScoverageXmlReader.read(file)
+        // need to ensure all the ids are unique otherwise the coverage object will have stmt collisions
+        id = id + 1
+        subcoverage.statements foreach { stmt => coverage add stmt.copy(id = id)}
+    }
+    coverage
+  }
+}

scalac-scoverage-plugin/src/main/scala/scoverage/report/ScoverageXmlReader.scala

@@ -14,7 +14,6 @@ object ScoverageXmlReader {
   def read(file: File): Coverage = {
     val xml = XML.loadFile(file)
 
-    var id = 0
     val coverage = Coverage()
     (xml \\ "statement") foreach { node => {
 
@@ -39,12 +38,10 @@ object ScoverageXmlReader {
         method.text,
         source.text)
 
-      id = id + 1
-
       coverage add Statement(
         source.text,
         location,
-        id,
+        0, // ids are irrelevant in the XML form
         start.text.toInt,
         end.text.toInt,
         line.text.toInt,