scalastyle-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
Facsimile - A Discrete-Event Simulation Library
Copyright © 2004-2016, Michael J Allen.

This file is part of Facsimile.

Facsimile is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later
version.

Facsimile is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with Facsimile. If not,
see http://www.gnu.org/licenses/.

The developers welcome all comments, suggestions and offers of assistance. For further information, please visit the
project home page at:

  http://www.facsim.org/

Thank you for your interest in the Facsimile project!

IMPORTANT NOTE: All patches (modifications to existing files and/or the addition of new files) submitted for inclusion
as part of the official Facsimile code base, must comply with the published Facsimile Coding Standards. If your code
fails to comply with the standard, then your patches will be rejected. For further information, please visit the coding
standards at:

  http://www.facsim.org/Documentation/CodingStandards/
========================================================================================================================
XML configuration file for Scalastyle.

NOTE: This file is maintained as part of the Facsimile "skeleton" project, and is common to a number of other Facsimile
projects, termed client projects. It must only be modified in the "skeleton" project, with changes being merged into
client projects. Refer to the skeleton project for further details:

  https://github.com/Facsimile/skeleton
========================================================================================================================
-->
<scalastyle>
 <name>Facsimile project standard Scalastyle configuration</name>

<!--
Horizontal tab characters are completely forbidden in source files.

Rationale: tabs are rendered inconsistently in source file editors. If used, this results in improperly indented sources
when switching to a different editor, or when a different user employs the same editor with a different tab
configuration. The only means of avoiding "tab hell" is to completely forbid the use of tabs, and insist on spaces
instead.
-->

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

<!--
Trailing whitespace is forbidden at the end of each source line.

Rationale: Trailing whitespace is untidy and can lead to version control issues - particularly during merges.
-->

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

<!--
Source line lengths cannot exceed 79 characters.

Rationale: Source lines that are longer than 79 characters will either wrap or truncate on the majority of command
prompt windows, terminals and printers. If viewing or editing on a phone or tablet, restricting source line length also
makes sense. Overall, source readability is maintained if the maximum line length is not allowed to exceed this value.
However, Scala source files typically benefit from longer source line length, and modern PC & tablet screens readily
accommodate such files. A common convention is to allow 120 character line lengths, and this has been adopted by
Facsimile.
-->

  <check class="org.scalastyle.file.FileLineLengthChecker" enabled="true" level="error">
    <parameters>
      <parameter name="maxLineLength"><![CDATA[120]]></parameter>
      <parameter name="tabSize"><![CDATA[8]]></parameter>
    </parameters>
  </check>

<!--
Each source file must commence with a standard header.

Rationale: The header is required to ensure that all sources have a correct copyright and distribution notice, which
must be up-to-date and valid for all sources.
-->

  <check class="org.scalastyle.file.HeaderMatchesChecker" enabled="true" level="error">
    <parameters>
      <parameter name="header"><![CDATA[/*
Facsimile -- A Discrete-Event Simulation Library
Copyright © 2004-2016, Michael J Allen.

This file is part of Facsimile.

Facsimile is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later
version.

Facsimile is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with Facsimile. If not, see
http://www.gnu.org/licenses/lgpl.

The developers welcome all comments, suggestions and offers of assistance. For further information, please visit the
project home page at:

  http://facsim.org/

Thank you for your interest in the Facsimile project!

IMPORTANT NOTE: All patches (modifications to existing files and/or the addition of new files) submitted for inclusion
as part of the official Facsimile code base, must comply with the published Facsimile Coding Standards. If your code
fails to comply with the standard, then your patches will be rejected. For further information, please visit the coding
standards at:

  http://facsim.org/Documentation/CodingStandards/
========================================================================================================================]]></parameter>
    </parameters>
  </check>

<!--
Package object names are lowercase alphanumeric, with occasional underscores. The first character must be a lowercase
character.

Rationale: This is a common Scala convention that should not be violated without a very good reason.
-->

  <check class="org.scalastyle.scalariform.PackageObjectNamesChecker" enabled="true" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[^[a-z][0-9a-z_]*$]]></parameter>
    </parameters>
  </check>

<!--
Object names are alphanumeric, starting with an uppercase character.

Although it cannot be enforced by Scalastyle, the convention is that object names are also in camel case.

Rationale: This is a common Scala convention that should not be violated without a very good reason.
-->

  <check class="org.scalastyle.scalariform.ObjectNamesChecker" enabled="true" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[^[A-Z][0-9A-Za-z]*$]]></parameter>
    </parameters>
  </check>

<!--
Class names are alphanumeric, starting with an uppercase character.

Although it cannot be enforced by Scalastyle, the convention is that class names are also in camel case.

Rationale: This is a common Scala convention that should not be violated without a very good reason.
-->

  <check class="org.scalastyle.scalariform.ClassNamesChecker" enabled="true" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[^[A-Z][0-9A-Za-z]*$]]></parameter>
    </parameters>
  </check>

<!--
Class/trait(/object?) definitions that are empty should not have braces.

Rationale: Braces for such classes are redundant and need not be specified.
-->

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

<!--
Enforce use of a single uppercase character for the name of class/trait type parameters.

Rationale: This is a common Scala convention.
-->

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

<!--
Forbid the use of var fields.

Rationale: In strict functional programming, "var"s are not required and often lead to mutable state. Use of "var" is
occasionally necessary, in which case this check should be explicitly disabled.
-->

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

<!--
Ensure that all classes defining a custom "equals" method also define a custom "hashCode" method, and vice versa.

Rationale: Class instances that are determined to be equal should have identical hash codes also. Consequently, classes
that have custom "equals" methods should generally have custom "hashCode" methods also.
-->

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

<!--
Ensure that all classes defining a custom "equals" method override "equals(java.lang.Object)".

Rationale: The Scala "==" equality operator utilizes the left operand class's "equals(java.lang.Object)" method, which
should be redefined if any custom "equals" method is required.
-->

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

<!--
Ensure that no class defines a "clone" method.

Rationale: There is no point to cloning immutable objects, and cloning stateful objects should be a rare exception.
-->

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

<!--
Ensure that no class defines a "finalize" method.

Rationale: Finalize methods are unusual and rarely required in practice, so any use of such functions is most likely a
mistake.
-->

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

<!--
Ensure that Java-style "procedure"-style function declarations are not used.

For example,

  def soSomething {
    //...
  }

should be avoided, with one of the following preferred:

  def doSomething: Unit = {
    // ...
  }

or (which should still be avoided, since it includes the possibility that a non-Unit value will be returned):

  def doSomething = {
    // ...
  }

Rationale: Martin Odersky has hinted that the procedure declaration syntax may be deprecated in a future Scala release,
as it is problematical and prevents the Scala compiler from trapping certain compile-time errors. It would also reduce
the confusion of new Scala developers. In the meantime, this Scalastyle warning is useful as it forbids procedure
syntax.

Refer to https://issues.scala-lang.org/browse/SI-7605 for further information.
-->

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

<!--
Method names are typically alphanumeric, starting with a lowercase characters.

Although it cannot be enforced by Scalastyle, the convention is that method names are also in camel case.

Rationale: This is a common Scala convention that should not be violated without a very good reason. However, other
characters are occasionally used (say, for setter methods, operator methods, etc.).
-->

  <check class="org.scalastyle.scalariform.MethodNamesChecker" enabled="true" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[^[a-z][0-9A-Za-z]*$]]></parameter>
      <parameter name="ignoreRegex"><![CDATA[[0-9A-Za-z]*_\=$]]></parameter>
      <parameter name="ignoreOverride"><![CDATA[false]]></parameter>
    </parameters>
  </check>

<!--
Enforce use of braces in if-else statements longer than one line.

Rationale: If the statement follows the if, or else, statement on the same line, then it is permitted not to require
braces. However, multiline if or else statements must have braces. This is because it can be hard to determine visually
whether a statement is conditional upon an if or else condition. For example:

if (found) println ("Search complete")

is OK, since it is clear that the println statement is dependent upon the if condition being true. However:

if (found)
  println ("Search complete")
  println (s"Item found was: $itemFound")

Is visually misleading, since only the first println statement is dependent upon the if condition being true. This check
would fail such a statement and would require it to be rewritten as:

if (found) {
  println ("Search complete")
  println (s"Item found was: $itemFound")
}

or as:

if (found) {
  println ("Search complete")
}
println (s"Item found was: $itemFound")

as appropriate.
-->

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

<!--
Warn against redundant if-else blocks.

For example, expressions such as:

if (cond) true else false

Should be replaced by simply:

cond

Rationale: Redundancy makes code more opaque and difficult to read.
-->

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

<!--
Enforce the use of braces over parentheses in for comprehensions.

That is, enforce:

for {
  p <-people
  if (p.isRetired)
} yield p

over

for (
  p <- people;
  if (p.isRetired)
) yield p

Rationale: The brace style is cleaner and does not require semicolons at the all but the last statement. Braces also
look more correct for multi-line code.
-->

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

<!--
Flag complex Boolean expressions.

Rationale: Code that is overly complex and that can be simplified should be.
-->

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

<!--
Ensure that all long constants are denoted using an uppercase L.

Rationale: Lowercase Ls can appear indistinguisable from 1s in some fonts. By enforcing uppercase Ls, clarity reigns.
-->

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

<!--
Require named constants instead of "magic numbers" in the code.

Rationale: Named constants are far more readable and self-documenting than mere numbers. (Numbers explicitly ignored
below are not treated as magic.)
-->

  <check class="org.scalastyle.scalariform.MagicNumberChecker" enabled="true" level="error">
    <parameters>
      <parameter name="ignore"><![CDATA[0,1,2]]></parameter>
    </parameters>
  </check>

<!--
Prevent string literals from appearing multiple times.

Rationale: String literals that appear multiple times is a maintenance chore; such strings should be stored in a value
instead.
-->

  <check class="org.scalastyle.scalariform.MultipleStringLiteralsChecker" enabled="true" level="error">
    <parameters>
      <parameter name="allowed"><![CDATA[1]]></parameter>
      <parameter name="ignoreRegex"><![CDATA[^""$]]></parameter>
    </parameters>
  </check>

<!--
Reject code that contains "???" values (not implemented statement).

Rationale: Leaving unimplemented code in commits is not good practice and will cause code rejection. However, the use of
"???" is strongly encouraged to document unimplemented features during development.
-->

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

<!--
Forbid the use of "return" statements in Scala.

Rationale: It is common Scala practice to strongly discourage use of the "return" statement (which begs the question,
"why does Scala even have a return statement?"). This check enforces the practice.
-->

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

<!--
Enforce use of Scala @deprecated annotation over Java equivalent.
-->

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

<!--
Guard against forbidden tokens, in this case use of asInstanceOf and isInstanceOf.

Rationale: Scala always has a better alternative for these methods, so they are forbidden.
-->

  <check class="org.scalastyle.scalariform.TokenChecker" enabled="true" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[^[ai]sInstanceOf$]]></parameter>
    </parameters>
    <customMessage>Casting methods are forbidden.</customMessage>
  </check>

<!--
Ensure that left brackets ([) are not followed by whitespace.

Rationale: This is simply an adopted Facsimile code style convention.
-->

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

<!--
The following checks are not currently utilized by the Facsimile project.
-->

  <check class="org.scalastyle.file.FileLengthChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maxFileLength"><![CDATA[800]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.SpacesAfterPlusChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.SpacesBeforePlusChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.UnderscoreImportChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.ImportGroupingChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.IllegalImportsChecker" enabled="false" level="error">
    <parameters>
      <parameter name="illegalImports"><![CDATA[sun._,java.awt._]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.ParameterNumberChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maxParameters"><![CDATA[8]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.NoWhitespaceBeforeLeftBracketChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.NullChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.StructuralTypeChecker" enabled="false" level="error" />
  <check class="org.scalastyle.file.RegexChecker" enabled="false" level="error">
    <parameters>
      <parameter name="regex"><![CDATA[println]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.NumberOfTypesChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maxTypes"><![CDATA[30]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.CyclomaticComplexityChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maximum"><![CDATA[10]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.LowercasePatternMatchChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.MethodLengthChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maxLength"><![CDATA[50]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.NumberOfMethodsInTypeChecker" enabled="false" level="error">
    <parameters>
      <parameter name="maxMethods"><![CDATA[30]]></parameter>
    </parameters>
  </check>
  <check class="org.scalastyle.scalariform.PublicMethodsHaveTypeChecker" enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.VarLocalChecker"  enabled="false" level="error" />
  <check class="org.scalastyle.scalariform.WhileChecker" enabled="false" level="error" />
  <check class="org.scalastyle.file.NewLineAtEofChecker" enabled="false" level="error" />
  <check class="org.scalastyle.file.NoNewLineAtEofChecker" enabled="false" level="error" />
</scalastyle>