<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC
    "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
    "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">

<!-- This is a checkstyle configuration file. For descriptions of
what the following rules do, please see the checkstyle configuration
page at http://checkstyle.sourceforge.net/config.html -->

<!-- Checks with numbered comments refer to recommendations made
by Joshua Bloch in his book Effective Java -->

<module name="Checker">
  <module name="SuppressionFilter"> <!-- baseline-gradle: README.md -->
      <property name="file" value="${config_loc}/suppressions.xml"/>
  </module>
  <property name="charset" value="UTF-8"/>
  <module name="FileTabCharacter">
    <!-- Checks that there are no tab characters in the file.-->
  </module>

  <module name="RegexpSingleline">
    <!-- Checks that FIXME is not used in comments.  TODO is preferred. -->
    <property name="format" value="((//.*)|(\*.*))FIXME" />
    <property name="message" value='TODO is preferred to FIXME.  e.g. "TODO(johndoe): Refactor when v2 is released."' />
  </module>

  <!-- Checks that String.toUpper/LowerCase() is never used without locale. -->
  <module name="RegexpSingleline">
    <property name="format" value="\.to(Upper|Lower)Case\(\)"/>
    <property name="message" value="String.toUpper/LowerCase() can have unexpected results depending on locale. Either set the locale explicitly - e.g., toUpperCase(Locale.ENGLISH) - or use Ascii.toUpper/LowerCase(...) instead." />
  </module>

  <!-- Checks that DateTime.now(...) is always passed a DateTimeZone parameter. -->
  <module name="RegexpSingleline">
    <property name="format" value="DateTime\.now\(\)"/>
    <property name="message" value="DateTime.now() must be called with a DateTimeZone parameter, e.g. DateTime.now(UTC)" />
  </module>

  <!-- Checks that Javadoc does not include a malformed @see tag. -->
  <module name="RegexpSingleline">
    <property name="format" value='@see\s\"http(|s)://'/>
    <property name="message" value='Your Javadocs appear to use invalid &lt;a&gt; tag syntax in @see tags. Please use the correct syntax: @see &lt;a href="http(s)://your_url"&gt;url_description&lt;/a&gt;'/>
  </module>

  <!-- Checks that java.util.Optional is used instead of Guava's Optional. -->
  <module name="RegexpSingleline">
    <property name="format" value="com\.google\.common\.base\.Optional"/>
    <property name="message" value="Use java.util.Optional instead of Guava's Optional."/>
  </module>

  <!-- Checks that the deprecated ExpectedException is not used. -->
  <module name="RegexpSingleline">
    <property name="format" value="org\.junit\.rules\.ExpectedException"/>
    <property name="message" value="Use assertThrows and expectThrows instead of the deprecated methods on ExpectedException."/>
  </module>

  <module name="LineLength">
    <!-- Checks if a line is too long. -->
    <property name="max" value="${com.puppycrawl.tools.checkstyle.checks.sizes.LineLength.max}" default="100"/>
    <property name="severity" value="error"/>

    <!-- Ignore lines that have any series of 80 or more non-whitespace characters.
    These lines likely cannot be broken.
    -->
    <property name="ignorePattern"
        value="${com.puppycrawl.tools.checkstyle.checks.sizes.LineLength.ignorePattern}"
        default=".*[^ ]{80,}.*"/>
  </module>

  <!-- All Java AST specific tests live under TreeWalker module. -->
  <module name="TreeWalker">

    <!--
    IMPORT CHECKS
    -->

    <module name="RedundantImport">
      <property name="severity" value="error"/>
    </module>

    <module name="AvoidStarImport">
      <property name="severity" value="error"/>
    </module>

    <module name="UnusedImports">
      <!-- DPL is a notable violator of this rule. -->
      <property name="severity" value="error"/>
      <!-- Imports used only in Javadoc are tolerated. See http://b/838496 -->
      <property name="processJavadoc" value="true"/>
      <message key="import.unused" value="Unused import: {0}." />
    </module>

    <module name="ImportOrder">
      <!-- Checks for out of order import statements. -->
      <metadata name="altname" value="ImportOrder"/>
      <property name="severity" value="warning"/>
      <!-- This ensures that static imports go first. -->
      <property name="option" value="top"/>
      <property name="tokens" value="STATIC_IMPORT, IMPORT"/>
      <property name="separatedStaticGroups" value="true"/>
      <property name="sortStaticImportsAlphabetically" value="true"/>
      <message key="import.ordering" value="Wrong order for {0} import."/>
    </module>

    <!--
    JAVADOC CHECKS
    -->

    <module name="JavadocTypeCheck">
      <!-- Item 28 - Write doc comments for all exposed API elements. -->
      <!-- Ensure all classes with visibility greater than or equal to
        protected have class level documentation. -->
      <property name="scope" value="protected"/>
      <property name="severity" value="error"/>
      <!-- Style guide doesn't prohibit custom tags. Typos will be caught by other tools. -->
      <property name="allowUnknownTags" value="true"/>
      <property name="allowMissingParamTags" value="true"/>
      <message key="javadoc.missing" value="Missing a Javadoc comment."/>
    </module>

    <!--
    NAMING CHECKS
    -->

    <!-- Item 38 - Adhere to generally accepted naming conventions -->
    <module name="PackageName">
      <!-- Validates identifiers for package names against the
        supplied expression. -->
      <property name="format" value="^([a-z][a-z0-9]*)(\.[a-z][a-z0-9]*)*$"/>
      <property name="severity" value="warning"/>
    </module>

    <module name="TypeNameCheck">
      <!-- Validates static, final fields against the supplied expression. -->
      <metadata name="altname" value="TypeName"/>
      <property name="severity" value="warning"/>
      <property name="format" value="^[A-Z][a-zA-Z0-9]*(_CustomFieldSerializer)?$"/>
    </module>

   <module name="MemberNameCheck">
      <!-- Validates non-static members against the supplied expression. -->
      <metadata name="altname" value="MemberName"/>
      <property name="applyToPublic" value="true"/>
      <property name="applyToProtected" value="true"/>
      <property name="applyToPackage" value="true"/>
      <property name="applyToPrivate" value="true"/>
      <!-- allows for googles deprecated foo_ member naming scheme -->
      <property name="format" value="^[a-z][a-zA-Z0-9]*_?$"/>
      <property name="severity" value="warning"/>
    </module>

    <module name="MethodNameCheck">
      <!-- Validates identifiers for method names. -->
      <metadata name="altname" value="MethodName"/>
      <property name="format" value="^([a-z][a-zA-Z0-9]*(_[a-zA-Z0-9]+)*|__constructor__|__staticInitializer__)$"/>
      <property name="severity" value="warning"/>
    </module>

    <module name="ParameterName">
      <!-- Validates identifiers for method parameters against the
        expression "^[a-z][a-zA-Z0-9]*$". -->
      <property name="severity" value="warning"/>
    </module>

    <module name="LocalFinalVariableName">
      <!-- Validates identifiers for local final variables against the
        expression "^[a-z][a-zA-Z0-9]*$". -->
      <property name="severity" value="warning"/>
    </module>

    <module name="LocalVariableName">
      <!-- Validates identifiers for local variables against the
        expression "^[a-z][a-zA-Z0-9]*$". -->
      <property name="severity" value="warning"/>
    </module>

    <!--
    LENGTH and CODING CHECKS
    -->

    <module name="OperatorWrap">
      <property name="option" value="nl"/>
      <property name="tokens" value="QUESTION, EQUAL, NOT_EQUAL, DIV, PLUS, MINUS, STAR, MOD, SR, BSR, GE, GT, SL, LE, LT, BXOR, BOR, LOR, BAND, LAND, TYPE_EXTENSION_AND, LITERAL_INSTANCEOF"/>
    </module>

    <module name="LeftCurly">
      <!-- Checks for placement of the left curly brace ('{'). -->
      <property name="severity" value="warning"/>
    </module>

    <module name="RightCurly">
      <property name="option" value="same"/>
      <property name="severity" value="warning"/>
    </module>

    <!-- Checks for braces around if and else blocks -->
    <module name="NeedBraces">
      <property name="severity" value="warning"/>
      <property name="tokens" value="LITERAL_IF, LITERAL_ELSE, LITERAL_FOR, LITERAL_WHILE, LITERAL_DO"/>
    </module>

    <!-- Checks for empty catch blocks in non-test files. -->
    <module name="EmptyCatchBlock">
      <property name="exceptionVariableName" value="expected"/>
      <property name="severity" value="error"/>
      <message key="catchBlock.empty"
               value="Empty catch blocks are not allowed. If this is an expected exception, it should be named 'expected'."/>
    </module>

    <!--
    MODIFIERS CHECKS
    -->

    <module name="ModifierOrder">
      <!-- Warn if modifier order is inconsistent with JLS3 8.1.1, 8.3.1, and
           8.4.3.  The prescribed order is:
           public, protected, private, abstract, static, final, transient, volatile,
           synchronized, native, strictfp
        -->
    </module>

    <!--
    WHITESPACE CHECKS
    -->

    <module name="WhitespaceAround">
      <!-- Checks that various tokens are surrounded by whitespace.
           This includes most binary operators and keywords followed
           by regular or curly braces.
      -->
      <property name="tokens" value="ASSIGN, BAND, BAND_ASSIGN, BOR,
        BOR_ASSIGN, BSR, BSR_ASSIGN, BXOR, BXOR_ASSIGN, COLON, DIV, DIV_ASSIGN,
        EQUAL, GE, GT, LAND, LE, LITERAL_CATCH, LITERAL_DO, LITERAL_ELSE,
        LITERAL_FINALLY, LITERAL_FOR, LITERAL_IF, LITERAL_RETURN,
        LITERAL_SYNCHRONIZED, LITERAL_TRY, LITERAL_WHILE, LOR, LT, MINUS,
        MINUS_ASSIGN, MOD, MOD_ASSIGN, NOT_EQUAL, PLUS, PLUS_ASSIGN, QUESTION,
        SL, SL_ASSIGN, SR_ASSIGN, STAR, STAR_ASSIGN"/>
      <property name="severity" value="error"/>
      <property name="ignoreEnhancedForColon" value="false"/>
    </module>

    <module name="WhitespaceAfter">
      <!-- Checks that commas, semicolons and typecasts are followed by
           whitespace.
      -->
      <property name="tokens" value="COMMA, SEMI, TYPECAST"/>
    </module>

    <module name="NoWhitespaceAfter">
      <!-- Checks that there is no whitespace after various unary operators.
           Linebreaks are allowed.
      -->
      <property name="tokens" value="BNOT, DEC, DOT, INC, LNOT, UNARY_MINUS,
        UNARY_PLUS"/>
      <property name="allowLineBreaks" value="true"/>
      <property name="severity" value="error"/>
    </module>

    <module name="NoWhitespaceBefore">
      <!-- Checks that there is no whitespace before various unary operators.
           Linebreaks are allowed.
      -->
      <property name="tokens" value="SEMI, DOT, POST_DEC, POST_INC"/>
      <property name="allowLineBreaks" value="true"/>
      <property name="severity" value="error"/>
    </module>

    <module name="ParenPad">
      <!-- Checks that there is no whitespace before close parens or after
           open parens. Allows whitespace after open parens if it is followed
           by the end of a line or by the start of a comment. Allows whitespace
           before close parens if it is preceeded by the start of a line or by
           the end of a block comment.
      -->
      <metadata name="altname" value="ParenPad"/>
      <property name="severity" value="warning"/>
    </module>
  </module>
</module>
