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class="theme-doc-breadcrumbs breadcrumbsContainer_Z_bl" aria-label="Breadcrumbs"><ul class="breadcrumbs" itemscope="" itemtype="https://schema.org/BreadcrumbList"><li class="breadcrumbs__item"><a aria-label="Home page" class="breadcrumbs__link" href="/"><svg viewBox="0 0 24 24" class="breadcrumbHomeIcon_YNFT"><path d="M10 19v-5h4v5c0 .55.45 1 1 1h3c.55 0 1-.45 1-1v-7h1.7c.46 0 .68-.57.33-.87L12.67 3.6c-.38-.34-.96-.34-1.34 0l-8.36 7.53c-.34.3-.13.87.33.87H5v7c0 .55.45 1 1 1h3c.55 0 1-.45 1-1z" fill="currentColor"></path></svg></a></li><li class="breadcrumbs__item">Introduction<meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active">Extending detekt<meta itemprop="position" content="2"></li></ul></nav>Version: 1.23.8<div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>Extending detekt</h1></header>The following page describes how to extend detekt and how to customize it to your domain-specific needs. The associated code samples to this guide can be found in the package <a href="https://github.com/detekt/detekt/tree/main/detekt-sample-extensions" target="_blank" rel="noopener noreferrer">detekt/detekt-sample-extensions</a>. <h4 class="anchor anchorWithStickyNavbar_LWe7" id="custom-rulesets"><a name="customrulesets">Custom RuleSets</a><a href="#custom-rulesets" class="hash-link" aria-label="Direct link to custom-rulesets" title="Direct link to custom-rulesets"></a></h4> detekt uses the <code>ServiceLoader</code> pattern to collect all instances of <code>RuleSetProvider</code> interfaces. So it is possible to define rules/rule sets and enhance detekt with your own flavor. <div class="theme-admonition theme-admonition-caution admonition_xJq3 alert alert--warning"><div class="admonitionHeading_Gvgb"><svg viewBox="0 0 16 16"><path fill-rule="evenodd" d="M8.893 1.5c-.183-.31-.52-.5-.887-.5s-.703.19-.886.5L.138 13.499a.98.98 0 0 0 0 1.001c.193.31.53.501.886.501h13.964c.367 0 .704-.19.877-.5a1.03 1.03 0 0 0 .01-1.002L8.893 1.5zm.133 11.497H6.987v-2.003h2.039v2.003zm0-3.004H6.987V5.987h2.039v4.006z"></path></svg>Attention</div><div class="admonitionContent_BuS1">You need a <code>resources/META-INF/services/io.gitlab.arturbosch.detekt.api.RuleSetProvider</code> file which has as content the fully qualified name of your <code>RuleSetProvider</code> e.g. <code>io.gitlab.arturbosch.detekt.sample.extensions.SampleProvider</code>.</div></div> You can use our <a href="https://github.com/detekt/detekt-custom-rule-template" target="_blank" rel="noopener noreferrer">GitHub template</a> to have a basic scaffolding to develop your own custom rules. Another option is to clone the provided <a href="https://github.com/detekt/detekt/tree/main/detekt-sample-extensions" target="_blank" rel="noopener noreferrer">detekt/detekt-sample-extensions</a> project. <div class="theme-admonition theme-admonition-note admonition_xJq3 alert alert--secondary"><div class="admonitionHeading_Gvgb"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M6.3 5.69a.942.942 0 0 1-.28-.7c0-.28.09-.52.28-.7.19-.18.42-.28.7-.28.28 0 .52.09.7.28.18.19.28.42.28.7 0 .28-.09.52-.28.7a1 1 0 0 1-.7.3c-.28 0-.52-.11-.7-.3zM8 7.99c-.02-.25-.11-.48-.31-.69-.2-.19-.42-.3-.69-.31H6c-.27.02-.48.13-.69.31-.2.2-.3.44-.31.69h1v3c.02.27.11.5.31.69.2.2.42.31.69.31h1c.27 0 .48-.11.69-.31.2-.19.3-.42.31-.69H8V7.98v.01zM7 2.3c-3.14 0-5.7 2.54-5.7 5.68 0 3.14 2.56 5.7 5.7 5.7s5.7-2.55 5.7-5.7c0-3.15-2.56-5.69-5.7-5.69v.01zM7 .98c3.86 0 7 3.14 7 7s-3.14 7-7 7-7-3.12-7-7 3.14-7 7-7z"></path></svg>note</div><div class="admonitionContent_BuS1">It's important that the dependency of <code>io.gitlab.arturbosch.detekt:detekt-api</code> is configured as <code>compileOnly</code> (as in the examples). You can read more information about this <a href="https://github.com/detekt/detekt/issues/7883" target="_blank" rel="noopener noreferrer">here</a>.</div></div> Own rules have to extend the abstract Rule class and override the <code>visitXXX()</code>-functions from the AST. A <code>RuleSetProvider</code> must be implemented, which declares a <code>RuleSet</code> in the <code>instance()</code>-function. To leverage the configuration mechanism of detekt you must pass the Config object from your rule set provider to your rule. An <code>Issue</code> property defines what ID and message should be printed on the console or on any other output format. Example of a custom rule: <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">class TooManyFunctions(config: Config) : Rule( config, "This rule reports a file with an excessive function count.", ) { private val threshold = 10 private var amount: Int = 0 override fun visitKtFile(file: KtFile) { super.visitKtFile(file) if (amount > threshold) { report(CodeSmell(Entity.from(file), "Too many functions can make the maintainability of a file costlier")) } amount = 0 } override fun visitNamedFunction(function: KtNamedFunction) { super.visitNamedFunction(function) amount++ } } </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> Example of a much preciser rule in terms of more specific CodeSmell constructor and Rule attributes: <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">class TooManyFunctions2(config: Config) : Rule( config, "This rule reports a file with an excessive function count.", ) { private val threshold: Int by config(defaultValue = 10) private var amount: Int = 0 override fun visitKtFile(file: KtFile) { super.visitKtFile(file) if (amount > threshold) { report(ThresholdedCodeSmell(issue, entity = Entity.from(file), metric = Metric(type = "SIZE", value = amount, threshold = threshold), message = "The file ${file.name} has $amount function declarations. " + "Threshold is specified with $threshold.", references = emptyList()) ) } amount = 0 } override fun visitNamedFunction(function: KtNamedFunction) { super.visitNamedFunction(function) amount++ } } </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> If you want your rule to be configurable, write down your properties inside the detekt.yml file. Please note that this will only take effect, if the <code>Config</code> object is passed on by the <code>RuleSetProvider</code> to the rule itself. <div class="language-yaml codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-yaml codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">MyRuleSet: TooManyFunctions2: active: true threshold: 5 OtherRule: active: false </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> By specifying the rule set and rule ids, detekt will use the sub configuration of <code>TooManyFunctions2</code>: <code>val threshold = valueOrDefault("threshold", THRESHOLD)</code> <div class="theme-admonition theme-admonition-note admonition_xJq3 alert alert--secondary"><div class="admonitionHeading_Gvgb"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M6.3 5.69a.942.942 0 0 1-.28-.7c0-.28.09-.52.28-.7.19-.18.42-.28.7-.28.28 0 .52.09.7.28.18.19.28.42.28.7 0 .28-.09.52-.28.7a1 1 0 0 1-.7.3c-.28 0-.52-.11-.7-.3zM8 7.99c-.02-.25-.11-.48-.31-.69-.2-.19-.42-.3-.69-.31H6c-.27.02-.48.13-.69.31-.2.2-.3.44-.31.69h1v3c.02.27.11.5.31.69.2.2.42.31.69.31h1c.27 0 .48-.11.69-.31.2-.19.3-.42.31-.69H8V7.98v.01zM7 2.3c-3.14 0-5.7 2.54-5.7 5.68 0 3.14 2.56 5.7 5.7 5.7s5.7-2.55 5.7-5.7c0-3.15-2.56-5.69-5.7-5.69v.01zM7 .98c3.86 0 7 3.14 7 7s-3.14 7-7 7-7-3.12-7-7 3.14-7 7-7z"></path></svg>note</div><div class="admonitionContent_BuS1">As of version 1.2.0 detekt now verifies if all configured properties actually exist in a configuration created by <code>--generate-config</code>. This means that by default detekt does not know about your new properties. Therefore we need to mention them in the configuration under <code>config>excludes</code>.</div></div> <div class="language-yaml codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-yaml codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">config: validation: true # 1. exclude rule set 'sample' and all its nested members # 2. exclude every property in every rule under the rule set 'sample' excludes: "sample.*,sample>.*>.*" </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> <h5 class="anchor anchorWithStickyNavbar_LWe7" id="testing-your-rules"><a name="testing">Testing your rules</a><a href="#testing-your-rules" class="hash-link" aria-label="Direct link to testing-your-rules" title="Direct link to testing-your-rules"></a></h5> To test your rules, add the dependency on <code>detekt-test</code> to your project: <code>testCompile "io.gitlab.arturbosch.detekt:detekt-test:$version"</code>. The easiest way to detect issues with your newly created rule is to use the <code>lint</code> extension function: <ul> <li><code>Rule.lint(StringContent/Path/KtFile): List<Finding></code></li> </ul> If you need to reuse the Kotlin file for performance reasons within similar test cases, please use one of these functions: <ul> <li><code>compileContentForTest(content: String): KtFile</code></li> <li><code>compileForTest(path: Path): KtFile</code></li> </ul> <h4 class="anchor anchorWithStickyNavbar_LWe7" id="custom-processors"><a name="customprocessors">Custom Processors</a><a href="#custom-processors" class="hash-link" aria-label="Direct link to custom-processors" title="Direct link to custom-processors"></a></h4> Custom processors can be used for example to implement additional project metrics. When for whatever reason you want to count all loop statements inside your code base, you could write something like: <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">class NumberOfLoopsProcessor : FileProcessListener { override fun onProcess(file: KtFile) { val visitor = LoopVisitor() file.accept(visitor) file.putUserData(numberOfLoopsKey, visitor.numberOfLoops) } companion object { val numberOfLoopsKey = Key<Int>("number of loops") } class LoopVisitor : DetektVisitor() { internal var numberOfLoops = 0 override fun visitLoopExpression(loopExpression: KtLoopExpression) { super.visitLoopExpression(loopExpression) numberOfLoops++ } } } </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> To let detekt know about the new processor, we specify a <code>resources/META-INF/services/io.gitlab.arturbosch.detekt.api.FileProcessListener</code> file with the full qualify name of our processor as the content: <code>io.gitlab.arturbosch.detekt.sample.extensions.processors.NumberOfLoopsProcessor</code>. To test the code we use the <code>detekt-test</code> module and write a JUnit 5 testcase. <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">class NumberOfLoopsProcessorTest { @Test fun `should expect two loops`() { val code = """ fun main() { for (i in 0..10) { while (i < 5) { println(i) } } } """ val ktFile = compileContentForTest(code) NumberOfLoopsProcessor().onProcess(ktFile) assertThat(ktFile.getUserData(NumberOfLoopsProcessor.numberOfLoopsKey)).isEqualTo(2) } } </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> <h4 class="anchor anchorWithStickyNavbar_LWe7" id="custom-reports"><a name="customreports">Custom Reports</a><a href="#custom-reports" class="hash-link" aria-label="Direct link to custom-reports" title="Direct link to custom-reports"></a></h4> detekt allows you to extend the console output and to create custom output formats. If you want to customize the output, take a look at the <code>ConsoleReport</code> and <code>OutputReport</code> classes. All they need are an implementation of the <code>render()</code>-function which takes an object with all findings and returns a string to be printed out. <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">abstract fun render(detektion: Detektion): String? </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> <h4 class="anchor anchorWithStickyNavbar_LWe7" id="let-detekt-know-about-your-extensions"><a name="configureextensions">Let detekt know about your extensions</a><a href="#let-detekt-know-about-your-extensions" class="hash-link" aria-label="Direct link to let-detekt-know-about-your-extensions" title="Direct link to let-detekt-know-about-your-extensions"></a></h4> So you have implemented your own rules or other extensions and want to integrate them into your <code>detekt</code> run? Great, make sure to have a <code>jar</code> with all your needed dependencies minus the ones <code>detekt</code> brings itself. Take a look at our <a href="https://github.com/detekt/detekt/tree/main/detekt-sample-extensions" target="_blank" rel="noopener noreferrer">sample project</a> on how to achieve this with gradle. <h5 class="anchor anchorWithStickyNavbar_LWe7" id="integrate-your-extension-with-the-detekt-cli">Integrate your extension with the detekt CLI<a href="#integrate-your-extension-with-the-detekt-cli" class="hash-link" aria-label="Direct link to Integrate your extension with the detekt CLI" title="Direct link to Integrate your extension with the detekt CLI"></a></h5> Mention your <code>jar</code> with the <code>--plugins</code> flag when calling the cli fatjar: <div class="language-sh codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-sh codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">detekt --input ... --plugins /path/to/my/jar </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> <h5 class="anchor anchorWithStickyNavbar_LWe7" id="integrate-your-extension-with-the-detekt-gradle-plugin">Integrate your extension with the Detekt Gradle Plugin<a href="#integrate-your-extension-with-the-detekt-gradle-plugin" class="hash-link" aria-label="Direct link to Integrate your extension with the Detekt Gradle Plugin" title="Direct link to Integrate your extension with the Detekt Gradle Plugin"></a></h5> For example <code>detekt</code> itself provides a wrapper over <a href="https://github.com/pinterest/ktlint" target="_blank" rel="noopener noreferrer">ktlint</a> as a custom <code>formatting</code> rule set. To enable it, we add the published dependency to <code>detekt</code> via the <code>detektPlugins</code> configuration: <h6 class="anchor anchorWithStickyNavbar_LWe7" id="gradle-kotlingroovy-dsl">Gradle (Kotlin/Groovy DSL)<a href="#gradle-kotlingroovy-dsl" class="hash-link" aria-label="Direct link to Gradle (Kotlin/Groovy DSL)" title="Direct link to Gradle (Kotlin/Groovy DSL)"></a></h6> <div class="language-kotlin codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-kotlin codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv">dependencies { detektPlugins("io.gitlab.arturbosch.detekt:detekt-formatting:1.23.8") } </code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></button></div></div></div> <h5 class="anchor anchorWithStickyNavbar_LWe7" id="pitfalls">Pitfalls<a href="#pitfalls" class="hash-link" aria-label="Direct link to Pitfalls" title="Direct link to Pitfalls"></a></h5> <ul> <li>All rules are disabled by default and have to be explicitly enabled in the <code>detekt</code> yaml configuration file.</li> <li>If you do not pass the <code>Config</code> object from the <code>RuleSetProvider</code> to the rule, the rule is active, but you will not be able to use any configuration options or disable the rule via config file.</li> <li>If your extension is part of your project and you integrate it like <code>detektPlugins project(":my-rules")</code> make sure that this subproject is build before <code>gradle detekt</code> is run. In the <code>kotlin-dsl</code> you could add something like <code>tasks.withType<Detekt> { dependsOn(":my-rules:assemble") }</code> to explicitly run <code>detekt</code> only after your extension sub project is built.</li> <li>If you use detekt for your Android project, and if you want to integrate all your custom rules in a new module, please make sure that you created a pure kotlin module which has no Android dependencies. <code>apply plugin: "kotlin"</code> is enough to make it work.</li> <li>Sometimes when you run detekt task, you may not see the violations detected by your custom rules. In this case open a terminal and run <code>./gradlew --stop</code> to stop gradle daemons and run the task again.</li> <li>If you are configuring a custom detekt task at the root project level, you will need to apply the detektPlugins at the root project as well (not subprojects). See <a href="https://github.com/detekt/detekt/issues/3989#issuecomment-890331512" target="_blank" rel="noopener noreferrer">this issue</a> for more.</li> </ul></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="row margin-top--sm theme-doc-footer-edit-meta-row"><div class="col"><a href="https://github.com/detekt/detekt/edit/main/website/versioned_docs/version-1.23.8/introduction/extensions.md" target="_blank" rel="noopener noreferrer" class="theme-edit-this-page"><svg fill="currentColor" height="20" width="20" viewBox="0 0 40 40" class="iconEdit_Z9Sw" aria-hidden="true"><g><path d="m34.5 11.7l-3 3.1-6.3-6.3 3.1-3q0.5-0.5 1.2-0.5t1.1 0.5l3.9 3.9q0.5 0.4 0.5 1.1t-0.5 1.2z m-29.5 17.1l18.4-18.5 6.3 6.3-18.4 18.4h-6.3v-6.2z"></path></g></svg>Edit this page</a></div><div class="col lastUpdated_JAkA"></div></div></footer></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/docs/introduction/suppressors"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">Suppressors</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/docs/introduction/snapshots"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">Using Snapshots</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"></div></div></div></div></main></div></div></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Docs</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/docs/gettingstarted/gradle">Getting Started with Gradle</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/gettingstarted/cli">Getting Started with the CLI</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/rules/comments">Rules Documentation</a></li></ul></div><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://kotlinlang.slack.com/archives/C88E12QH4" target="_blank" rel="noopener noreferrer" class="footer__link-item">Slack<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://stackoverflow.com/questions/tagged/detekt" target="_blank" rel="noopener noreferrer" class="footer__link-item">Stack Overflow<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div><div class="col footer__col"><div class="footer__title">More</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/blog">Blog</a></li><li class="footer__item"><a href="https://github.com/detekt/detekt" target="_blank" rel="noopener noreferrer" class="footer__link-item">GitHub<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://detekt.dev/kdoc" target="_blank" rel="noopener noreferrer" class="footer__link-item">KDoc<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div></div><div class="footer__bottom text--center"><div class="footer__copyright">Copyright © 2025 detekt team - Built with Docusaurus.</div></div></div></footer></div> </body> </html>