Android Lint Variant Baseline

A Gradle plugin that adds support to baseline XML per Android variant for both app and library modules.

How does it work?

The plugin stores each lint-baseline.xml file under a corresponding variant folder. When you run lint for a specific variant, the plugin registers a dependency on a task that copies the baseline file to the location you specify in lintOptions block.

Usage

1. Gradle configuration

Configure the plugin as follow. Note the baseline file configuration in android.lintOptions closure! It is recommended to set it to the module's build dir since the variant specific one will be copied just before lint starts.

plugins {
    id "com.nimroddayan.lint-variant-baseline" version "0.2.0"
}

// Apply the plugin and configure Android Gradle plugin Lint options per each module
subprojects {
    apply plugin: 'com.nimroddayan.lint-variant-baseline'

    def configureKotlin = {
        android {
            lintOptions {
                // It is recommended to set the baseline file path to build dir
                // because the variant specific one will be copied from variant source dir just before lint starts
                baseline file("$buildDir/lint-baseline.xml")
                checkDependencies false
                checkReleaseBuilds true
                abortOnError true
        
                // Custom Lint configuration file for ignoring specific lint checks
                lintConfig file("$rootDir/lint-config.xml")
            }
        }
        
        plugins.withType(com.android.build.gradle.AppPlugin, configureKotlin)
        plugins.withType(com.android.build.gradle.LibraryPlugin, configureKotlin)
    }
}

2. Generating the baseline files per module variant

Let's assume that we have one product flavor defined in the app and some feature modules like so:

android {
    flavorDimensions "type"
    productFlavors {
        free {
            dimension "type"
        }
        paid {
            dimension "type"
        }
    }
}

Now that you have the Gradle config in place, you can run the tasks to generate baseline files per each module in the project per variant:

./gradlew generateLintBaselinePaidRelease -Dlint.baselines.continue=true \
generateLintBaselineFreeRelease -Dlint.baselines.continue=true \
generateLintBaselinePaidDebug -Dlint.baselines.continue=true \
generateLintBaselineFreeDebug -Dlint.baselines.continue=true

For library modules which don't have product flavors, you can run generate baseline files like so:

./gradlew generateLintBaselineRelease -Dlint.baselines.continue=true \
generateLintBaselineRelease -Dlint.baselines.continue=true \
generateLintBaselineDebug -Dlint.baselines.continue=true \
generateLintBaselineDebug -Dlint.baselines.continue=true

The above will execute the tasks for all modules which apply the Android Gradle app or library plugin.

Note that -Dlint.baselines.continue=true is necessary so that lint will continue without failing the build.

When the tasks are finished, you will see baseline files in the variant source folder. For example:

/
/app/src/paidRelease/lint-baseline.xml
/app/src/paidDebug/lint-baseline.xml
/app/src/freeRelease/lint-baseline.xml
/app/src/freeDebug/lint-baseline.xml
/feature/src/paidRelease/lint-baseline.xml
/feature/src/paidDebug/lint-baseline.xml
/feature/src/freeRelease/lint-baseline.xml
/feature/src/freeDebug/lint-baseline.xml

You should add these baseline files to source control.

3. Running lint

After you generated the baseline files, run lint as you'd normally would. The plugin adds a task which is run prior to the lint task to copy the variant specific baseline file to the path specified in lintOptions.baseline.

For example: ./gradlew lintPaidRelease.

Available tasks

The plugin exposes the following tasks:

generateLintBaseline{VariantName} -Dlint.baselines.continue=true

This task will run lint to generate the baseline file at the location you specified in lintOptions block and after that, it will copy the file to the variant specific folder. Note that this file will overwrite existing baseline files.

Example: ./gradlew generateLintBaselinePaidRelease -Dlint.baselines.continue=true

Note that -Dlint.baselines.continue=true is necessary so that lint will continue without failing the build.

deleteLintBaseline

Deletes the baseline file specified in lintOptions if it exists. This task can be used when you're setting up this plugin to delete old baseline files.

Example: ./gradlew deleteLintBaseline

copyLintBaseline{VariantName}

This task is run just before lint{VariantName} as a dependency. It copies the variant specific baseline file from variant source dir to the destination specified in lintOptions.baseline. This task is used internally and it is not meant to be run by the user.

Example: ./gradlew copyLintBaselinePaidRelease

Contributing

Make a Pull Request.

Reporting an issue

Use Github issue tracker.

License

Copyright 2020 Nimrod Dayan nimroddayan.com

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.