Scalastyle Config

scalastyle-config.xml

<!--

If you wish to turn off checking for a section of code, you can put a comment in the source
before and after the section, with the following syntax:

  // scalastyle:off
  ...  // stuff that breaks the styles
  // scalastyle:on

You can also disable only one rule, by specifying its rule id, as specified in:
  http://www.scalastyle.org/rules-0.7.0.html

  // scalastyle:off no.finalize
  override def finalize(): Unit = ...
  // scalastyle:on no.finalize
-->

<scalastyle>
  <name>Scalastyle standard configuration</name>

  <!-- ================================================================================ -->
  <!--                               mandatory rules                                    -->
  <!-- ================================================================================ -->

  <check level="error" class="org.scalastyle.file.FileTabChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.SpacesAfterPlusChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.SpacesBeforePlusChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.file.WhitespaceEndOfLineChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.file.FileLineLengthChecker" enabled="true">
    <parameters>
      <parameter name="maxLineLength"><![CDATA[100]]></parameter>
      <parameter name="tabSize"><![CDATA[2]]></parameter>
      <parameter name="ignoreImports">true</parameter>
    </parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.ClassNamesChecker" enabled="true">
    <parameters><parameter name="regex"><![CDATA[[A-Z][A-Za-z]*]]></parameter></parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.ObjectNamesChecker" enabled="true">
    <parameters><parameter name="regex"><![CDATA[[A-Z][A-Za-z]*]]></parameter></parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.PackageObjectNamesChecker" enabled="true">
    <parameters><parameter name="regex"><![CDATA[^[a-z][A-Za-z]*$]]></parameter></parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.ParameterNumberChecker" enabled="true">
    <parameters><parameter name="maxParameters"><![CDATA[10]]></parameter></parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.NoFinalizeChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.CovariantEqualsChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.StructuralTypeChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.UppercaseLChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.IfBraceChecker" enabled="true">
    <parameters>
      <parameter name="singleLineAllowed"><![CDATA[true]]></parameter>
      <parameter name="doubleLineAllowed"><![CDATA[true]]></parameter>
    </parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.PublicMethodsHaveTypeChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.file.NewLineAtEofChecker" enabled="true"></check>

  <check customId="nonascii" level="error" class="org.scalastyle.scalariform.NonASCIICharacterChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.SpaceAfterCommentStartChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.EnsureSingleSpaceBeforeTokenChecker" enabled="true">
   <parameters>
     <parameter name="tokens">ARROW, EQUALS, ELSE, TRY, CATCH, FINALLY, LARROW, RARROW</parameter>
   </parameters>
  </check>

  <check level="error" class="org.scalastyle.scalariform.EnsureSingleSpaceAfterTokenChecker" enabled="true">
    <parameters>
     <parameter name="tokens">ARROW, EQUALS, COMMA, COLON, IF, ELSE, DO, WHILE, FOR, MATCH, TRY, CATCH, FINALLY, LARROW, RARROW</parameter>
    </parameters>
  </check>

  <!-- ??? usually shouldn't be checked into the code base. -->
  <check level="error" class="org.scalastyle.scalariform.NotImplementedErrorUsage" enabled="true"></check>

  <!-- all printlns need to be wrapped in '// scalastyle:off/on println' -->
  <check customId="println" level="error" class="org.scalastyle.scalariform.TokenChecker" enabled="true">
    <parameters><parameter name="regex">^println$</parameter></parameters>
    <customMessage><![CDATA[Are you sure you want to println? If yes, wrap the code block with
      // scalastyle:off println
      println(...)
      // scalastyle:on println]]></customMessage>
  </check>

  <check customId="runtimeaddshutdownhook" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">Runtime\.getRuntime\.addShutdownHook</parameter></parameters>
    <customMessage><![CDATA[
      Are you sure that you want to use Runtime.getRuntime.addShutdownHook? In most cases, you should use
      ShutdownHookManager.addShutdownHook instead.
      If you must use Runtime.getRuntime.addShutdownHook, wrap the code block with
      // scalastyle:off runtimeaddshutdownhook
      Runtime.getRuntime.addShutdownHook(...)
      // scalastyle:on runtimeaddshutdownhook
    ]]></customMessage>
  </check>

  <check customId="mutablesynchronizedbuffer" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">mutable\.SynchronizedBuffer</parameter></parameters>
    <customMessage><![CDATA[
      Are you sure that you want to use mutable.SynchronizedBuffer? In most cases, you should use
      java.util.concurrent.ConcurrentLinkedQueue instead.
      If you must use mutable.SynchronizedBuffer, wrap the code block with
      // scalastyle:off mutablesynchronizedbuffer
      mutable.SynchronizedBuffer[...]
      // scalastyle:on mutablesynchronizedbuffer
    ]]></customMessage>
  </check>

  <check customId="classforname" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">Class\.forName</parameter></parameters>
    <customMessage><![CDATA[
      Are you sure that you want to use Class.forName? In most cases, you should use Utils.classForName instead.
      If you must use Class.forName, wrap the code block with
      // scalastyle:off classforname
      Class.forName(...)
      // scalastyle:on classforname
    ]]></customMessage>
  </check>

  <check customId="awaitresult" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">Await\.result</parameter></parameters>
    <customMessage><![CDATA[
      Are you sure that you want to use Await.result? In most cases, you should use ThreadUtils.awaitResult instead.
      If you must use Await.result, wrap the code block with
      // scalastyle:off awaitresult
      Await.result(...)
      // scalastyle:on awaitresult
    ]]></customMessage>
  </check>

  <!-- JavaConversions should be replaced with JavaConverters -->
  <check customId="javaconversions" level="error" class="org.scalastyle.scalariform.TokenChecker" enabled="true">
    <parameters><parameter name="regex">JavaConversions</parameter></parameters>
    <customMessage>Instead of importing implicits in scala.collection.JavaConversions._, import
    scala.collection.JavaConverters._ and use .asScala / .asJava methods</customMessage>
  </check>

  <check level="error" class="org.scalastyle.scalariform.DisallowSpaceBeforeTokenChecker" enabled="true">
    <parameters>
      <parameter name="tokens">COMMA</parameter>
    </parameters>
  </check>

  <!-- Single Space between ')' and '{' -->
  <check customId="SingleSpaceBetweenRParenAndLCurlyBrace" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">\)\{</parameter></parameters>
    <customMessage><![CDATA[
      Single Space between ')' and `{`.
    ]]></customMessage>
  </check>

  <check customId="NoScalaDoc" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">(?m)^(\s*)/[*][*].*$(\r|)\n^\1  [*]</parameter></parameters>
    <customMessage>Use Javadoc style indentation for multiline comments</customMessage>
  </check>

  <check customId="OmitBracesInCase" level="error" class="org.scalastyle.file.RegexChecker" enabled="true">
    <parameters><parameter name="regex">case[^\n>]*=>\s*\{</parameter></parameters>
    <customMessage>Omit braces in case clauses.</customMessage>
  </check>

  <check level="error" class="org.scalastyle.scalariform.EqualsHashCodeChecker" enabled="true"></check>

  <check level="error" class="org.scalastyle.scalariform.MethodNamesChecker" enabled="true">
    <parameters>
      <parameter name="regex"><![CDATA[^[^A-Z]+[A-Za-z0-9]*$]]></parameter>
    </parameters>
  </check>

  <!-- ================================================================================ -->
  <!--                 rules desirable to enforce but not mandatory                     -->
  <!-- ================================================================================ -->

  <check level="warning" class="org.scalastyle.scalariform.IllegalImportsChecker" enabled="true">
    <parameters><parameter name="illegalImports"><![CDATA[sun._,java.awt._]]></parameter></parameters>
  </check>

  <!-- Low level code and to interface with 3rd party code -->
  <check level="warning" class="org.scalastyle.scalariform.NullChecker" enabled="true"></check>

  <!-- Every project has a lot of magic numbers ... -->
  <check level="warning" class="org.scalastyle.scalariform.MagicNumberChecker" enabled="true">
    <parameters><parameter name="ignore">-1,0,1,2,3</parameter></parameters>
  </check>

  <!-- Ideally the following two rules should be configurable to rule out string interpolation. -->
  <check level="warning" class="org.scalastyle.scalariform.NoWhitespaceBeforeLeftBracketChecker" enabled="true"></check>
  <check level="warning" class="org.scalastyle.scalariform.NoWhitespaceAfterLeftBracketChecker" enabled="true"></check>

  <!-- ================================================================================ -->
  <!--                                  disabled rules                                  -->
  <!-- ================================================================================ -->

  <!-- Opposite of this: NewLineAtEofChecker -->
  <check level="error" class="org.scalastyle.file.NoNewLineAtEofChecker" enabled="false"></check>

  <!-- This one complains about all kinds of random things. Disable. -->
  <check level="error" class="org.scalastyle.scalariform.SimplifyBooleanExpressionChecker" enabled="false"></check>

  <!-- Return is used quite a bit for control flows and guards -->
  <check level="error" class="org.scalastyle.scalariform.ReturnChecker" enabled="false"></check>

  <!-- Doesn't seem super big deal here ... -->
  <check level="error" class="org.scalastyle.scalariform.NoCloneChecker" enabled="false"></check>

  <!-- Doesn't seem super big deal here ... -->
  <check level="error" class="org.scalastyle.file.FileLengthChecker" enabled="false">
    <parameters><parameter name="maxFileLength">800></parameter></parameters>
  </check>

  <!-- Doesn't seem super big deal here ... -->
  <check level="error" class="org.scalastyle.scalariform.NumberOfTypesChecker" enabled="false">
    <parameters><parameter name="maxTypes">30</parameter></parameters>
  </check>

  <!-- Doesn't seem super big deal here ... -->
  <check level="error" class="org.scalastyle.scalariform.CyclomaticComplexityChecker" enabled="false">
    <parameters><parameter name="maximum">10</parameter></parameters>
  </check>

  <!-- Doesn't seem super big deal here ... -->
  <check level="error" class="org.scalastyle.scalariform.MethodLengthChecker" enabled="false">
    <parameters><parameter name="maxLength">50</parameter></parameters>
  </check>

  <!-- Not exactly feasible to enforce this right now. -->
  <!-- It is also infrequent that somebody introduces a new class with a lot of methods. -->
  <check level="error" class="org.scalastyle.scalariform.NumberOfMethodsInTypeChecker" enabled="false">
    <parameters><parameter name="maxMethods"><![CDATA[30]]></parameter></parameters>
  </check>

  <!-- No reasons to enforce this right now. -->
  <check level="error" class="org.scalastyle.file.HeaderMatchesChecker" enabled="false">
    <parameters>
       <parameter name="header"></parameter>
    </parameters>
  </check>

</scalastyle>