Meet detekt, a static code analysis tool for the Kotlin programming language. Visit the project website for installation guides, rule descriptions, configuration options and more.

• Code smell analysis for your Kotlin projects.
• Highly configurable rule sets.
• Generate baselines to suppress existing issues for legacy projects while making sure no new issues are introduced.
• Suppress issues in source files using @Suppress annotations.
• Support for different report formats: HTML, Markdown, SARIF, XML (Checkstyle) and custom reports.
• Extend detekt with custom rule sets and reports.
• Complexity reports based on lines of code, cyclomatic complexity and number of code smells.
• First party integration with Gradle with our Gradle plugin.
• A community of third party plugins that adds more rules and features to detekt.

• Changelog and migration guides
• Available CLI options
• Rule set and rule descriptions
• Writing custom rules and extending detekt
• Suppressing issues in code
• Suppressing issues via baseline file
• Configuring detekt
• Sample Gradle integrations examples:
  • multi project (Kotlin DSL)
  • single project (Groovy DSL)
  • single project (Unofficial Maven plugin)

curl -sSLO https://github.com/detekt/detekt/releases/download/v[version]/detekt-cli-[version]-all.jar
java -jar detekt-cli-[version]-all.jar --help

You can find other ways to install detekt here

plugins {
    id("io.gitlab.arturbosch.detekt").version("[version]")
}

repositories {
    mavenCentral()
}

detekt {
    buildUponDefaultConfig = true // preconfigure defaults
    allRules = false // activate all available (even unstable) rules.
    config.setFrom("$projectDir/config/detekt.yml") // point to your custom config defining rules to run, overwriting default behavior
    baseline = file("$projectDir/config/baseline.xml") // a way of suppressing issues before introducing detekt
}

tasks.withType<Detekt>().configureEach {
    reports {
        html.required.set(true) // observe findings in your browser with structure and code snippets
        xml.required.set(true) // checkstyle like format mainly for integrations like Jenkins
        txt.required.set(true) // similar to the console output, contains issue signature to manually edit baseline files
        sarif.required.set(true) // standardized SARIF format (https://sarifweb.azurewebsites.net/) to support integrations with GitHub Code Scanning
        md.required.set(true) // simple Markdown format
    }
}

// Groovy DSL
tasks.withType(Detekt).configureEach {
    jvmTarget = "1.8"
}
tasks.withType(DetektCreateBaselineTask).configureEach {
    jvmTarget = "1.8"
}

// or

// Kotlin DSL
tasks.withType<Detekt>().configureEach {
    jvmTarget = "1.8"
}
tasks.withType<DetektCreateBaselineTask>().configureEach {
    jvmTarget = "1.8"
}

See maven central for releases and sonatype for snapshots.

If you want to use a SNAPSHOT version, you can find more info on this documentation page.

Gradle 6.8.3+ is the minimum requirement. However, the recommended versions together with the other tools recommended versions are:

The list of recommended versions for previous detekt version is listed here.

detekt itself provides a wrapper over ktlint as the formatting rule set which can be easily added to the Gradle configuration:

dependencies {
    detektPlugins("io.gitlab.arturbosch.detekt:detekt-formatting:[version]")
}

Similarly, there are extra rule sets available for detekt from detekt:

dependencies {
    detektPlugins("io.gitlab.arturbosch.detekt:detekt-rules-libraries:[version]")
    detektPlugins("io.gitlab.arturbosch.detekt:detekt-rules-ruleauthors:[version]")
}

For more info visit the Detekt Marketplace.

Likewise custom extensions can be added to detekt.

See CONTRIBUTING

Thanks to all the people who contributed to detekt!

As mentioned in...

• driodcon London 2021 - Detekt - State of the Union
• KotlinConf 2018 - Safe(r) Kotlin Code - Static Analysis Tools for Kotlin by Marvin Ramin
• droidcon NYC 2018 - Static Code Analysis For Kotlin
• Kotlin on Code Quality Tools - by @vanniktech Slides Presentation
• Integrating detekt in the Workflow
• Check the quality of Kotlin code
• Kotlin Static Analysis Tools
• Are you still smelling it?: A comparative study between Java and Kotlin language by Flauzino et al.
• Preventing software antipatterns with Detekt

Integrations:

• IntelliJ integration
• SonarQube integration
• Codacy
• Gradle plugin that configures Error Prone, Checkstyle, PMD, CPD, Lint, Detekt & Ktlint
• Violations Lib is a Java library for parsing report files like static code analysis.
• sputnik is a free tool for static code review and provides support for detekt
• Gradle Static Analysis plugin
• Detekt Maven plugin that wraps the Detekt CLI
• Detekt Bazel plugin that wraps the Detekt CLI
• Gradle plugin that helps facilitate GitHub PR checking and automatic commenting of violations
• Codefactor
• GitHub Action: Detekt All
• GitHub Action: Setup detekt
• Sonatype Lift

Custom rules and reports from 3rd parties can be found on our Detekt Marketplace.

• JetBrains - Creating IntelliJ + Kotlin
• PMD & Checkstyle & ktlint - Ideas for threshold values and style rules