diff --git a/src/main/groovy/info/solidsoft/gradle/pitest/PitestPlugin.groovy b/src/main/groovy/info/solidsoft/gradle/pitest/PitestPlugin.groovy
index 7fda87d6..a79e29c2 100644
--- a/src/main/groovy/info/solidsoft/gradle/pitest/PitestPlugin.groovy
+++ b/src/main/groovy/info/solidsoft/gradle/pitest/PitestPlugin.groovy
@@ -105,6 +105,7 @@ class PitestPlugin implements Plugin<Project> {
         extension.useClasspathFile.set(false)
     }
 
+    @SuppressWarnings("UnnecessarySetter")  //Due to: task.sourceDirs.setFrom() in CodeNarc
     private void configureTaskDefault(PitestTask task) {
         task.testPlugin.set(extension.testPlugin)
         task.reportDir.set(extension.reportDir)
@@ -146,7 +147,7 @@ class PitestPlugin implements Plugin<Project> {
         task.excludedGroups.set(extension.excludedGroups)
         task.fullMutationMatrix.set(extension.fullMutationMatrix)
         task.includedTestMethods.set(extension.includedTestMethods)
-//        task.sourceDirs.set(project.providers.provider() { extension.mainSourceSets*.allSource.srcDirs.flatten() as Set })
+        task.sourceDirs.setFrom(extension.mainSourceSets.get()*.allSource)
         task.detectInlinedCode.set(extension.detectInlinedCode)
         task.timestampedReports.set(extension.timestampedReports)
         task.enableDefaultIncrementalAnalysis.set(extension.enableDefaultIncrementalAnalysis)
@@ -183,7 +184,6 @@ class PitestPlugin implements Plugin<Project> {
                 project.rootProject.buildscript.configurations[PITEST_CONFIGURATION_NAME]
             }
             mutableCodePaths = { calculateBaseMutableCodePaths() + (extension.additionalMutableCodePaths ?: []) }
-            sourceDirs = { extension.mainSourceSets.get()*.allSource.srcDirs.flatten() as Set }
         }
     }
 
diff --git a/src/main/groovy/info/solidsoft/gradle/pitest/PitestTask.groovy b/src/main/groovy/info/solidsoft/gradle/pitest/PitestTask.groovy
index 21c5d589..fec00aef 100644
--- a/src/main/groovy/info/solidsoft/gradle/pitest/PitestTask.groovy
+++ b/src/main/groovy/info/solidsoft/gradle/pitest/PitestTask.groovy
@@ -18,6 +18,7 @@ package info.solidsoft.gradle.pitest
 import groovy.transform.CompileStatic
 import groovy.transform.PackageScope
 import org.gradle.api.Incubating
+import org.gradle.api.file.ConfigurableFileCollection
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.FileCollection
 import org.gradle.api.file.RegularFileProperty
@@ -147,8 +148,7 @@ class PitestTask extends JavaExec {
     final SetProperty<String> includedTestMethods
 
     @InputFiles
-    @PathSensitive(PathSensitivity.RELATIVE)
-    Set<File> sourceDirs
+    final ConfigurableFileCollection sourceDirs
 
     @Input
     @Optional
@@ -273,7 +273,7 @@ class PitestTask extends JavaExec {
         excludedGroups = of.setProperty(String)
         fullMutationMatrix = of.property(Boolean)
         includedTestMethods = of.setProperty(String)
-//        sourceDirs = of.fileProperty()
+        sourceDirs = of.fileCollection()
         detectInlinedCode = of.property(Boolean)
         timestampedReports = of.property(Boolean)
         historyInputLocation = of.fileProperty()