diff --git a/src/dotty/tools/dotc/core/Periods.scala b/src/dotty/tools/dotc/core/Periods.scala
index 6efadab7f271..7118cb7bf0b3 100644
--- a/src/dotty/tools/dotc/core/Periods.scala
+++ b/src/dotty/tools/dotc/core/Periods.scala
@@ -136,9 +136,11 @@ object Periods {
 
   final val Nowhere = new Period(0)
 
-  final val InitialPeriod = Period(InitialRunId, FirstPhaseId)
 
-  final val InvalidPeriod = Period(NoRunId, NoPhaseId)
+  /** The number of bits needed to encode a phase identifier. */
+  final val PhaseWidth = 6
+  final val PhaseMask = (1 << PhaseWidth) - 1
+  final val MaxPossiblePhaseId = PhaseMask
 
   /** An ordinal number for compiler runs. First run has number 1. */
   type RunId = Int
@@ -152,8 +154,8 @@ object Periods {
   final val NoPhaseId = 0
   final val FirstPhaseId = 1
 
-  /** The number of bits needed to encode a phase identifier. */
-  final val PhaseWidth = 6
-  final val PhaseMask = (1 << PhaseWidth) - 1
-  final val MaxPossiblePhaseId = PhaseMask
+
+  final val InitialPeriod = Period(InitialRunId, FirstPhaseId)
+
+  final val InvalidPeriod = Period(NoRunId, NoPhaseId)
 }
diff --git a/src/dotty/tools/dotc/parsing/JavaTokens.scala b/src/dotty/tools/dotc/parsing/JavaTokens.scala
index 9530e0516196..c40532f44095 100644
--- a/src/dotty/tools/dotc/parsing/JavaTokens.scala
+++ b/src/dotty/tools/dotc/parsing/JavaTokens.scala
@@ -6,13 +6,7 @@ import collection.immutable.BitSet
 
 object JavaTokens extends TokensCommon {
   final val minToken = EMPTY
-  final val maxToken = DOUBLE
-
-  final val javaOnlyKeywords = tokenRange(INSTANCEOF, ASSERT)
-  final val sharedKeywords = BitSet( IF, FOR, ELSE, THIS, NULL, NEW, SUPER, ABSTRACT, FINAL, PRIVATE, PROTECTED,
-    OVERRIDE, EXTENDS, TRUE, FALSE, CLASS, IMPORT, PACKAGE, DO, THROW, TRY, CATCH, FINALLY, WHILE, RETURN )
-  final val primTypes = tokenRange(VOID, DOUBLE)
-  final val keywords = sharedKeywords | javaOnlyKeywords | primTypes
+  final val maxToken = 188
 
   /** keywords */
   final val INSTANCEOF = 101;       enter(INSTANCEOF, "instanceof")
@@ -89,4 +83,13 @@ object JavaTokens extends TokensCommon {
   final val LONG = 186;             enter(LONG, "long")
   final val FLOAT = 187;            enter(FLOAT, "float")
   final val DOUBLE = 188;           enter(DOUBLE, "double")
+
+  assert(maxToken == DOUBLE, "change if maxToken changes")
+
+  final val sharedKeywords = BitSet( IF, FOR, ELSE, THIS, NULL, NEW, SUPER, ABSTRACT, FINAL, PRIVATE, PROTECTED,
+    OVERRIDE, EXTENDS, TRUE, FALSE, CLASS, IMPORT, PACKAGE, DO, THROW, TRY, CATCH, FINALLY, WHILE, RETURN )
+  final val javaOnlyKeywords = tokenRange(INSTANCEOF, ASSERT)
+
+  final val primTypes = tokenRange(VOID, DOUBLE)
+  final val keywords = sharedKeywords | javaOnlyKeywords | primTypes
 }
diff --git a/src/dotty/tools/dotc/parsing/Tokens.scala b/src/dotty/tools/dotc/parsing/Tokens.scala
index 226a3710db2b..042353f9ab8a 100644
--- a/src/dotty/tools/dotc/parsing/Tokens.scala
+++ b/src/dotty/tools/dotc/parsing/Tokens.scala
@@ -141,7 +141,7 @@ abstract class TokensCommon {
 
 object Tokens extends TokensCommon {
   final val minToken = EMPTY
-  final val maxToken = XMLSTART
+  final val maxToken = 96
 
   final val INTERPOLATIONID = 10;  enter(INTERPOLATIONID, "string interpolator")
   final val SYMBOLLIT = 11;        enter(SYMBOLLIT, "symbol literal") // TODO: deprecate
@@ -188,6 +188,8 @@ object Tokens extends TokensCommon {
   /** XML mode */
   final val XMLSTART = 96;         enter(XMLSTART, "$XMLSTART$<") // TODO: deprecate
 
+  assert(XMLSTART == maxToken, "update if max token changes")
+
   final val alphaKeywords = tokenRange(IF, FORSOME)
   final val symbolicKeywords = tokenRange(USCORE, VIEWBOUND)
   final val symbolicTokens = tokenRange(COMMA, VIEWBOUND)
diff --git a/src/dotty/tools/dotc/util/Attachment.scala b/src/dotty/tools/dotc/util/Attachment.scala
index 8088b4cd09c5..b9652d11a95a 100644
--- a/src/dotty/tools/dotc/util/Attachment.scala
+++ b/src/dotty/tools/dotc/util/Attachment.scala
@@ -91,7 +91,7 @@ object Attachment {
     private[Attachment] var next: Link[_] = null
 
     final def pushAttachment[V](key: Key[V], value: V): Unit = {
-      assert(!getAttachment(key).isDefined, s"duplicate attachment for key $key")
+      assert(getAttachment(key).isEmpty, s"duplicate attachment for key $key")
       next = new Link(key, value, next)
     }
   }
diff --git a/test/dotty/partest/DPConsoleRunner.scala b/test/dotty/partest/DPConsoleRunner.scala
index fa6256398d47..66fce97da3cb 100644
--- a/test/dotty/partest/DPConsoleRunner.scala
+++ b/test/dotty/partest/DPConsoleRunner.scala
@@ -120,7 +120,7 @@ extends SuiteRunner(testSourcePath, fileManager, updateCheck, failed, javaCmdPat
       echo(statusLine(state))
       if (!state.isOk && isDiffy) {
         val differ = bold(red("% ")) + "diff "
-        state.transcript.dropWhile(s => !(s startsWith differ)) foreach (echo(_))
+        state.transcript.dropWhile(s => !(s startsWith differ)) foreach (echo)
         // state.transcript find (_ startsWith differ) foreach (echo(_)) // original
       }
     }
@@ -248,7 +248,7 @@ class DPTestRunner(testFile: File, suiteRunner: DPSuiteRunner) extends nest.Runn
   // so we ignore groups (tests suffixed with _1 and _2)
   override def groupedFiles(sources: List[File]): List[List[File]] = {
     val grouped = sources groupBy (_.group)
-    val flatGroup = List(grouped.keys.toList.sorted.map({ k => grouped(k) sortBy (_.getName) }).flatten)
+    val flatGroup = List(grouped.keys.toList.sorted.flatMap { k => grouped(k) sortBy (_.getName) })
     try { // try/catch because of bug in partest that throws exception
       if (flatGroup != super.groupedFiles(sources))
         throw new java.lang.UnsupportedOperationException()
diff --git a/test/test/ContextEscapeDetector.java b/test/test/ContextEscapeDetector.java
index c7768fd57647..237d8df2b793 100644
--- a/test/test/ContextEscapeDetector.java
+++ b/test/test/ContextEscapeDetector.java
@@ -1,6 +1,5 @@
 package test;
 
-import org.junit.runner.Description;
 import org.junit.runner.Result;
 import org.junit.runner.notification.RunListener;
 import org.junit.Assert;