com.diffplug.gradle.spotless && task clean(type: Delete){} Error:Cannot add task 'clean' as a task with that name already exists

Issue

This my build.gradle

buildscript {
    ext {
        ...
    }
    repositories {
        google()
        jcenter()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
        classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$navigationVersion"
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

plugins {
    id "com.diffplug.gradle.spotless" version "3.26.0"
}

allprojects {
    repositories {
        google()
        jcenter()

    }
}

spotless {
    kotlin {
        target "**/*.kt"
        ktlint(ktlintVersion).userData(['max_line_length' : '100'])
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

The original compilation was successful, but when the spotless was introduced, it caused this error:

com.diffplug.gradle.spotless && task clean(type: Delete){} Error:Cannot add task 'clean' as a task with that name already exists

So, I guess these two parts are conflicting, but I don’t know the specific reasons.

plugins {
    id "com.diffplug.gradle.spotless" version "3.26.0"
}
//...
task clean(type: Delete) {
    delete rootProject.buildDir
}

Solution

You have this task defined in your project-level build.gradle (as posted in your comments):

task clean(type: Delete) { 
    delete rootProject.buildDir 
}

Android Studio's Gradle wrapper already has a clean task defined, so there's no need to re-define it. Just delete that task from your project-level build.gradle file.

Answered By - BADSHAH