detekt

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.

Features

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.

Quick Start ...

with the command-line interface

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

with Gradle

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.

Requirements

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

Detekt Version	Gradle	Kotlin	AGP	Java Target Level	JDK Max Version
`1.23.5`	`8.5`	`1.9.22`	`8.2.0`	`1.8`	`17`

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

Adding more rule sets

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.