pmd-ruleset.xml

<?xml version="1.0"?>
<ruleset name="OpinionatedSalesforce" xmlns="http://pmd.sourceforge.net/ruleset/2.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://pmd.sourceforge.net/ruleset/2.0.0 https://pmd.sourceforge.io/ruleset_2_0_0.xsd">

    <description>Opinionated Salesforce Developer</description>

    <!-- IGNORE EXTERNAL LIBS -->
    <include-pattern>.*/force-app/main/default/.*</include-pattern>

    <!-- STANDARD RULES -->  
    
    <rule ref="category/apex/security.xml">
        <priority>1</priority>
        <!-- Salesforce Graph Engine does this better -->    
        <exclude name="ApexCRUDViolation" />    
    </rule>  

    <rule ref="category/apex/bestpractices.xml">      
        <priority>2</priority>   

        <exclude name="DebugsShouldUseLoggingLevel" /> <!-- Is buggy -->
        <exclude name="ApexUnitTestClassShouldHaveRunAs" /> <!-- No smart person does that -->
        <exclude name="ApexAssertionsShouldIncludeMessage" /> <!-- Better have a focused well named method -->
        <exclude name="ApexUnitTestClassShouldHaveAsserts" /> <!-- Stupid rule, a well-named test method is the assertion -->
    </rule>
    
    <rule ref="category/apex/design.xml">      
        <priority>2</priority>  

        <!-- Salesforce Graph Engine does this better --> 
        <exclude name="UnusedMethod" />

        <!-- Cognitive Complexity covers all of that better -->     
        <exclude name="AvoidDeeplyNestedIfStmts" />
        <exclude name="StdCyclomaticComplexity" />
        <exclude name="CyclomaticComplexity" />
        <exclude name="ExcessiveClassLength" />
        <exclude name="ExcessivePublicCount" />
        <exclude name="TooManyFields" />
        <exclude name="NcssTypeCount" />
    </rule>

    <rule ref="category/apex/performance.xml">      
        <priority>2</priority>   

        <exclude name="AvoidNonRestrictiveQueries" />  <!-- Stupid rule, sorry but no -->
        <exclude name="AvoidDebugStatements" />  <!-- Improved by XPath below --> 
    </rule>

    <rule name="DebugsNeedALoggingLevel" language="apex" message="Debug statements should use an explicit Debug Level" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>2</priority>
        <properties><property name="xpath"><value><![CDATA[

            //MethodCallExpression[lower-case(@FullMethodName)='system.debug'][count(//VariableExpression)>2]
        
        ]]></value></property></properties>
    </rule>

    <rule ref="category/apex/codestyle.xml">      
        <priority>3</priority>  
        
        <!-- Improve by disallowing _ in Classnames -->
        <exclude name="ClassNamingConventions" />  
    </rule>

    <rule ref="category/apex/codestyle.xml/ClassNamingConventions">
        <priority>3</priority> 
        <properties>
            <property name="testClassPattern" value="[A-Z][a-zA-Z0-9_]*" />
            <property name="abstractClassPattern" value="[A-Z][a-zA-Z0-9]*" />
            <property name="classPattern" value="[A-Z][a-zA-Z0-9]*(_t)?" />
            <property name="interfacePattern" value="[A-Z][a-zA-Z0-9]*" />
            <property name="enumPattern" value="[A-Z][a-zA-Z0-9]*" />
        </properties>
    </rule>  

    <rule ref="category/apex/errorprone.xml">      
        <priority>2</priority>  
    </rule>


    <!-- CUSTOM RULES -->

    <!-- Apex Rules -->

    <rule name="UnneededUseOfThisReducesReadability" language="apex" message="Unneeded use of this reduces readability" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

        //ThisVariableExpression[
            ancestor::VariableExpression
            and
            not(
                ancestor::ReturnStatement
                or
                ancestor::MethodCallExpression[ReferenceExpression/@Image = VariableExpression/@Image]
                or 
                ancestor::VariableExpression/@Image = ancestor::Method//Parameter/@Image
            )
        ]

        ]]></value></property></properties>
    </rule>

    <rule name="OnlyOneReturnPerMethod" language="apex" message="Method with multiple returns are confusing" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[
            
            //Method[count(.//ReturnStatement) > 1]

        ]]></value></property></properties>
    </rule>

    <rule name="TestsShouldNotStartWithTest" language="apex" message="Test results are harder to grasp when tests start with the word test" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //Method[
                starts-with(lower-case(@Image), "test") 
                and 
                descendant::ModifierNode/Annotation[@Image="IsTest"]
            ]

        ]]></value></property></properties>
    </rule>


    <rule name="DeclareWhatYouReturnFirstAndCallItResult" language="apex" message="What you return call it result and declare it in the first line" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //ReturnStatement[
                lower-case(@Image) != 'result' 
                and
                ancestor::Method[
                    @Synthetic = false() 
                    and 
                    lower-case(@ReturnType)!='void'
                ] 
                and
                preceding-sibling::VariableDeclarationStatements/VariableDeclaration[1][@Image != 'result'
            ]]

        ]]></value></property></properties>
    </rule>

    <rule name="NullValueCheckBeforeEmptyCheck" language="apex" message="Apex code must check != null before .isEmpty()" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>2</priority>
        <properties><property name="xpath"><value><![CDATA[

            //BooleanExpression[@Op="&&"][
                child::*[2][
                self::BooleanExpression[@Op="!="][
                    child::*[1][self::VariableExpression] and
                    child::*[2][self::LiteralExpression[@LiteralType="NULL"]]
                ]
                ]
            ]

        ]]></value></property></properties>
    </rule>

    <rule name="CheckIfProperFalsePositive" language="apex" message="Only False Positives can be supressed and need a proper comment." class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>5</priority>
        <properties><property name="xpath"><value><![CDATA[

            //Annotation[@Image='SuppressWarnings']/AnnotationParameter[starts-with(@Value, 'PMD.')]
        
        ]]></value></property></properties>
    </rule>
    
    <rule name="CommentsOftenExcuseForBadCodeAndTests" language="apex" message="Formal class or method comments are often an excuse for bad code and tests" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>4</priority>
        <properties><property name="xpath"><value><![CDATA[

            //FormalComment

        ]]></value></property></properties>
    </rule>

    <rule name="PreferRealObjectsOverStaticHelpers" language="apex" message="Use real objects with data and state instead of static messy helpers." class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //UserClass[
                count(.//Method) = count(.//Method/ModifierNode[@Static=true()])
                and count(.//Method) > 0
                and not(descendant::ModifierNode/Annotation[@Image='IsTest'])
                and not(.//Method/ModifierNode/Annotation[@Image='InvocableMethod' or @Image='AuraEnabled'])
            ]
            
        ]]></value></property></properties>
    </rule>

    <rule name="UseModernAssertClass" language="apex" message="Use the modern Assert class instead of legacy System.assert methods" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //MethodCallExpression[starts-with(lower-case(@FullMethodName), 'system.assert')]

        ]]></value></property></properties>
    </rule>

    <rule name="AssertionsShouldNotHaveMessages" language="apex" message="Assertions don't need messages - let your test method name do the explaining" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>4</priority>
        <properties><property name="xpath"><value><![CDATA[

            //MethodCallExpression[
                starts-with(lower-case(@FullMethodName), 'assert.')
                and count(./ReferenceExpression/following-sibling::*) > 2
            ]

        ]]></value></property></properties>
    </rule>

    <rule name="TestClassesMustEndWithUnderscoreTest" language="apex" message="Test classes must end with _Test suffix" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //UserClass[
                ModifierNode/Annotation[@Image='IsTest']
                and not(ends-with(@Image, '_Test'))
            ]

        ]]></value></property></properties>
    </rule>

    <rule name="TestClassesShouldBePrivate" language="apex" message="Test classes should be private - they're not part of your API" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //UserClass[
                ModifierNode/Annotation[@Image='IsTest']
                and ModifierNode[@Public = true() or @Global = true()]
            ]

        ]]></value></property></properties>
    </rule>

    <rule name="GetPrefixIsJustNoise" language="apex" message="Skip the 'get' prefix - account.name() reads better than account.getName()" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>4</priority>
        <properties><property name="xpath"><value><![CDATA[

            //Method[
                starts-with(@Image, 'get')
                and @Synthetic = false()
                and not(ancestor::UserClass/descendant::ModifierNode/Annotation[@Image='IsTest'])
            ]

        ]]></value></property></properties>
    </rule>

    <rule name="ClassNamesBecomeSelfFulfillingProphecies" language="apex" message="Service, Handler, Manager, Helper, Util, Wrapper - these names attract messy code like magnets" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>3</priority>
        <properties><property name="xpath"><value><![CDATA[

            //UserClass[
                matches(@Image, '.*(Service|Handler|Manager|Helper|Util|Wrapper)$')
                and not(descendant::ModifierNode/Annotation[@Image='IsTest'])
            ]

        ]]></value></property></properties>
    </rule>

    <!-- Metadata XML Rules -->

    <rule name="BumpApiVersion" language="xml" message="Metadata should use the latest API version." class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>2</priority>
        <properties><property name="xpath"><value><![CDATA[
                //apiVersion/text[number(@Image) < 50]

        ]]></value></property></properties>
    </rule>

    <!-- Flow Rules -->

    <rule name="DMLStatementInFlowLoop" language="xml" message="DML Operations shouldn't be done inside of Flow loops" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>2</priority>
        <properties><property name="xpath"><value><![CDATA[

            //Flow/loops//targetReference[not(ancestor::noMoreValuesConnector)]/text[@Image=//Flow/(recordCreates|recordDeletes|recordUpdates)/name/text/@Image]

        ]]></value></property></properties>
    </rule>

    <!-- Custom Objects / Fields Rules -->

    <rule name="MetadataRequiresDescription" language="xml" message="Add a description to explain custom metadata" class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>2</priority>
        <properties><property name="xpath"><value><![CDATA[

            //(CustomObject | CustomField | PermissionSet)[not(description)]

        ]]></value></property></properties>
    </rule>

    <!-- Profile and Permission Set Rules -->

    <rule name="ModifyOrViewAllOnPermSet" language="xml" message="Allowing this user permission can give access and ability to modify sensitive data." class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>1</priority>
        <properties><property name="xpath"><value><![CDATA[
    
            //PermissionSet/userPermissions[ name/text[@Image='ModifyAllData' or @Image='ViewAllData'] and enabled/text[@Image='true'] ]

        ]]></value></property></properties>
    </rule>

    <rule name="ViewSetupByNonSysAdmins" language="xml" message="Exposing the setup menu to non-authorized users." class="net.sourceforge.pmd.lang.rule.xpath.XPathRule">
        <priority>1</priority>
        <properties><property name="xpath"><value><![CDATA[

                //Profile/userPermissions[ pmd:fileName() != 'System Administrator' and enabled/text[@Image='true'] and name/text[@Image='ViewSetup'] ]
        
        ]]></value></property></properties>
    </rule>
</ruleset>