diff --git a/src/main/scala/com/typesafe/sbt/packager/debian/DebianPlugin.scala b/src/main/scala/com/typesafe/sbt/packager/debian/DebianPlugin.scala
index 04142da01..f1dd28583 100644
--- a/src/main/scala/com/typesafe/sbt/packager/debian/DebianPlugin.scala
+++ b/src/main/scala/com/typesafe/sbt/packager/debian/DebianPlugin.scala
@@ -91,8 +91,8 @@ object DebianPlugin extends AutoPlugin with DebianNativePackaging {
     packageSummary in Debian := (packageSummary in Linux).value,
     maintainer in Debian := (maintainer in Linux).value,
     validatePackageValidators in Debian := Seq(
-      nonEmptyMappings((linuxPackageMappings in Debian).value.flatMap(_.mappings)),
-      filesExist((linuxPackageMappings in Debian).value.flatMap(_.mappings)),
+      nonEmptyMappings((mappings in Debian).value),
+      filesExist((mappings in Debian).value),
       checkMaintainer((maintainer in Debian).value, asWarning = false)
     ),
     // override the linux sourceDirectory setting
diff --git a/src/main/scala/com/typesafe/sbt/packager/docker/DockerPlugin.scala b/src/main/scala/com/typesafe/sbt/packager/docker/DockerPlugin.scala
index 7116ffcae..e64eba484 100644
--- a/src/main/scala/com/typesafe/sbt/packager/docker/DockerPlugin.scala
+++ b/src/main/scala/com/typesafe/sbt/packager/docker/DockerPlugin.scala
@@ -402,11 +402,11 @@ object DockerPlugin extends AutoPlugin {
   }
 
   private[this] def validateExposedPorts(ports: Seq[Int], udpPorts: Seq[Int]): Validation.Validator = () => {
-    if (ports.isEmpty && udpPorts.isEmpty) {
-      List(
-        ValidationWarning(
-          description = "There are no exposed ports for your docker image",
-          howToFix = """| Configure the `dockerExposedPorts` or `dockerExposedUdpPorts` setting. E.g.
+    if(ports.isEmpty && udpPorts.isEmpty) {
+      List(ValidationWarning(
+        description = "There are no exposed ports for your docker image",
+        howToFix =
+          """| Configure the `dockerExposedPorts` or `dockerExposedUdpPorts` setting. E.g.
              |
              | // standard tcp ports
              | dockerExposedPorts ++= Seq(9000, 9001)
@@ -414,8 +414,7 @@ object DockerPlugin extends AutoPlugin {
              | // for udp ports
              | dockerExposedUdpPorts += 4444
           """.stripMargin
-        )
-      )
+      ))
     } else {
       List.empty
     }
@@ -424,12 +423,10 @@ object DockerPlugin extends AutoPlugin {
   private[this] def validateDockerVersion(dockerVersion: Option[DockerVersion]): Validation.Validator = () => {
     dockerVersion match {
       case Some(_) => List.empty
-      case None =>
-        List(
-          ValidationWarning(
-            description =
-              "sbt-native-packager wasn't able to identify the docker version. Some features may not be enabled",
-            howToFix = """|sbt-native packager tries to parse the `docker version` output. This can fail if
+      case None => List(ValidationWarning(
+        description = "sbt-native-packager wasn't able to identify the docker version. Some features may not be enabled",
+        howToFix =
+          """|sbt-native packager tries to parse the `docker version` output. This can fail if
              |
              |  - the output has changed:
              |    $ docker version --format '{{.Server.Version}}'
@@ -448,9 +445,10 @@ object DockerPlugin extends AutoPlugin {
              |  import com.typesafe.sbt.packager.docker.DockerVersion
              |  dockerVersion := Some(DockerVersion(17, 5, 0, Some("ce"))
           """.stripMargin
-          )
-        )
+      ))
     }
   }
 
+
+
 }
diff --git a/src/main/scala/com/typesafe/sbt/packager/validation/Validation.scala b/src/main/scala/com/typesafe/sbt/packager/validation/Validation.scala
index 302d1f152..f25b7afae 100644
--- a/src/main/scala/com/typesafe/sbt/packager/validation/Validation.scala
+++ b/src/main/scala/com/typesafe/sbt/packager/validation/Validation.scala
@@ -37,7 +37,7 @@ object Validation {
     * @return aggregated result of all validator function
     */
   def apply(validators: Seq[Validator]): Validation = validators.flatMap(_.apply()).foldLeft(Validation(Nil, Nil)) {
-    case (validation, error: ValidationError) => validation.copy(errors = validation.errors :+ error)
+    case (validation, error: ValidationError)     => validation.copy(errors = validation.errors :+ error)
     case (validation, warning: ValidationWarning) => validation.copy(warnings = validation.warnings :+ warning)
   }
 
diff --git a/src/main/scala/com/typesafe/sbt/packager/validation/ValidationKeys.scala b/src/main/scala/com/typesafe/sbt/packager/validation/ValidationKeys.scala
index d291a7018..e4babb20b 100644
--- a/src/main/scala/com/typesafe/sbt/packager/validation/ValidationKeys.scala
+++ b/src/main/scala/com/typesafe/sbt/packager/validation/ValidationKeys.scala
@@ -2,6 +2,7 @@ package com.typesafe.sbt.packager.validation
 
 import sbt._
 
+
 trait ValidationKeys {
 
   /**
@@ -19,4 +20,4 @@ trait ValidationKeys {
   val validatePackageValidators = taskKey[Seq[Validation.Validator]]("validator functions")
 }
 
-object ValidationKeys extends ValidationKeys
+object ValidationKeys extends ValidationKeys
\ No newline at end of file