diff --git a/main-settings/src/main/scala/sbt/InputTask.scala b/main-settings/src/main/scala/sbt/InputTask.scala
index 079aef869..16866a652 100644
--- a/main-settings/src/main/scala/sbt/InputTask.scala
+++ b/main-settings/src/main/scala/sbt/InputTask.scala
@@ -27,7 +27,7 @@ final class InputTask[T] private (val parser: State => Parser[Task[T]]) {
         Parser.parse(in, parser(s)) match {
           case Right(v) => Parser.success(v)
           case Left(msg) =>
-            val indented = msg.lines.map("   " + _).mkString("\n")
+            val indented = msg.linesIterator.map("   " + _).mkString("\n")
             Parser.failure(s"Invalid programmatic input:\n$indented")
       }
     )
@@ -47,7 +47,7 @@ object InputTask {
                 Parser.parse(in, it.parser(s)) match {
                   case Right(t) => Def.value(t)
                   case Left(msg) =>
-                    val indented = msg.lines.map("   " + _).mkString("\n")
+                    val indented = msg.linesIterator.map("   " + _).mkString("\n")
                     sys.error(s"Invalid programmatic input:\n$indented")
                 }
         )
diff --git a/main/src/main/scala/sbt/internal/LibraryManagement.scala b/main/src/main/scala/sbt/internal/LibraryManagement.scala
index 4b49c4bbe..1adae3fb7 100644
--- a/main/src/main/scala/sbt/internal/LibraryManagement.scala
+++ b/main/src/main/scala/sbt/internal/LibraryManagement.scala
@@ -99,7 +99,7 @@ private[sbt] object LibraryManagement {
             val culprit = t.getClass.getSimpleName
             log.warn(s"Update task caching failed due to $culprit.")
             log.warn("Report the following output to sbt:")
-            resolvedAgain.toString.lines.foreach(log.warn(_))
+            resolvedAgain.toString.linesIterator.foreach(log.warn(_))
             log.trace(t)
             resolvedAgain
           }
diff --git a/main/src/main/scala/sbt/internal/parser/SbtRefactorings.scala b/main/src/main/scala/sbt/internal/parser/SbtRefactorings.scala
index c9c2446dd..647e5d012 100644
--- a/main/src/main/scala/sbt/internal/parser/SbtRefactorings.scala
+++ b/main/src/main/scala/sbt/internal/parser/SbtRefactorings.scala
@@ -36,7 +36,7 @@ private[sbt] object SbtRefactorings {
     val sortedRecordedCommands = recordedCommands.sortBy(_._1)(reverseOrderingInt)
 
     val newContent = replaceFromBottomToTop(lines.mkString(END_OF_LINE), sortedRecordedCommands)
-    (file, newContent.lines.toList)
+    (file, newContent.linesIterator.toList)
   }
 
   private def replaceFromBottomToTop(
diff --git a/main/src/test/scala/sbt/internal/parser/EmbeddedXmlSpec.scala b/main/src/test/scala/sbt/internal/parser/EmbeddedXmlSpec.scala
index 007c89342..5ea38c01b 100644
--- a/main/src/test/scala/sbt/internal/parser/EmbeddedXmlSpec.scala
+++ b/main/src/test/scala/sbt/internal/parser/EmbeddedXmlSpec.scala
@@ -38,7 +38,7 @@ class EmbeddedXmlSpec extends CheckIfParsedSpec {
 
       split(buildSbt) must throwA[MessageOnlyException].like {
         case exception =>
-          val index = buildSbt.lines.indexWhere(line => line.contains(errorLine)) + 1
+          val index = buildSbt.linesIterator.indexWhere(line => line.contains(errorLine)) + 1
           val numberRegex = """(\d+)""".r
           val message = exception.getMessage
           val list = numberRegex.findAllIn(message).toList
diff --git a/main/src/test/scala/sbt/internal/parser/ErrorSpec.scala b/main/src/test/scala/sbt/internal/parser/ErrorSpec.scala
index eea63c0d8..a79fd91f7 100644
--- a/main/src/test/scala/sbt/internal/parser/ErrorSpec.scala
+++ b/main/src/test/scala/sbt/internal/parser/ErrorSpec.scala
@@ -10,9 +10,7 @@ package internal
 package parser
 
 import java.io.File
-
 import sbt.internal.util.MessageOnlyException
-
 import scala.io.Source
 
 class ErrorSpec extends AbstractSpec {
@@ -26,12 +24,13 @@ class ErrorSpec extends AbstractSpec {
       foreach(new File(rootPath).listFiles) { file =>
         print(s"Processing ${file.getName}: ")
         val buildSbt = Source.fromFile(file).getLines().mkString("\n")
-        SbtParser(file, buildSbt.lines.toSeq) must throwA[MessageOnlyException].like {
-          case exp =>
-            val message = exp.getMessage
-            println(s"${exp.getMessage}")
-            message must contain(file.getName)
-        }
+        SbtParser(file, buildSbt.linesIterator.toSeq) must throwA[MessageOnlyException]
+          .like {
+            case exp =>
+              val message = exp.getMessage
+              println(s"${exp.getMessage}")
+              message must contain(file.getName)
+          }
         containsLineNumber(buildSbt)
       }
     }
@@ -60,7 +59,9 @@ class ErrorSpec extends AbstractSpec {
           |val a = <a/><b/>
           |val s = '
         """.stripMargin
-      SbtParser(SbtParser.FAKE_FILE, buildSbt.lines.toSeq) must throwA[MessageOnlyException].like {
+      SbtParser(SbtParser.FAKE_FILE, buildSbt.linesIterator.toSeq) must throwA[
+        MessageOnlyException
+      ].like {
         case exp =>
           val message = exp.getMessage
           println(s"${exp.getMessage}")
diff --git a/project/Dependencies.scala b/project/Dependencies.scala
index 678b6b59b..43128851a 100644
--- a/project/Dependencies.scala
+++ b/project/Dependencies.scala
@@ -4,7 +4,7 @@ import sbt.contraband.ContrabandPlugin.autoImport._
 
 object Dependencies {
   // WARNING: Please Scala update versions in PluginCross.scala too
-  val scala212 = "2.12.6"
+  val scala212 = "2.12.7"
   val baseScalaVersion = scala212
 
   // sbt modules