Stalker

Stalker detects affected Java classes given a set of changed Java source files. It does this by examining bytecode and completing the closure on dependencies.

Usage

build.gradle

buildscript {
  repositories {
      mavenCentral()
  }
  dependencies {
      classpath "com.vandalsoftware.tools.gradle:stalker:0.4.+"
  }
}

Configuration

build.gradle

apply plugin: 'stalker'

stalker uses a project's source files and classpaths for detecting changes and provides a default configuration for these.

For java projects, the default configuration looks like:

stalker {
  srcRoot "src/main/java"
  srcRoot "src/test/java"
  srcClassPath "$buildDir/classes/main"
  srcClassPath "$buildDir/classes/test"
  targetClassPath "$buildDir/classes/test"
}

For android projects, the default configuration looks like:

stalker {
  srcRoot "src/main/java"
  srcRoot "src/androidTest/java"
  srcClassPath "$buildDir/classes/debug"
  srcClassPath "$buildDir/classes/release"
  targetClassPath "$buildDir/classes/test/debug"
  targetClassPath "$buildDir/classes/test/release"
}

For android projects that define productFlavors, the default configuration looks like:

stalker {
  srcRoot "src/main/java"
  srcRoot "src/androidTest/java"
  srcRoot "src/flavor1/java"
  srcClassPath "$buildDir/classes/flavor1/debug"
  srcClassPath "$buildDir/classes/flavor1/release"
  targetClassPath "$buildDir/classes/test/flavor1/debug"
  targetClassPath "$buildDir/classes/test/flavor1/release"
}

If you need to provide your own source files and classpaths, you may do so using the stalker extension.

stalker {
  srcRoot "src/main/java"
  srcClassPath "$buildDir/classes/main"
  targetClassPath "$buildDir/classes/test"
}

Currently, stalker obtains a list of changed files by relying on Git. To use it, you must be tracking a git repository in your working directory:

$ git init

By default, it will use HEAD as its reference. You can configure this by setting the revision property.

For example:

stalker {
  ...
  revison = project.has("rev") ? rev : "HEAD"
}

You might then run stalker like this...

$ ./gradlew stalk -Prev=a34dfef0 --info

...which outputs something along these lines.

com.vandalsoftware.android.common.IoUtils used by build/classes/test/com/vandalsoftware/android/common/IoUtilsTests.class
com.vandalsoftware.android.common.IoUtilsTests

That's pretty interesting but not particularly useful since the output is stuck on the command line. However, Stalker allows you to direct output anywhere you want.

build.gradle

stalker {
  standardOutput = new FileOutputStream(new File("out.txt"))
}

out.txt

com.vandalsoftware.android.common.IoUtilsTests

We can now take the output of this file and input it into any script we write to execute the tests. For example, in this imaginary Python script I wrote.

$ cat out.txt | test_runner.py -s mycooldevice

Taking it one step further, we can append a closure to the stalk task to run after it completes:

build.gradle

stalk << {
    affectedClasses.each() {
        println "adb shell am instrument -w -e class " + it + " com.vandalsoftware.android.tests/android.test.InstrumentationTestRunner"
    }
}

Which produces some output:

adb shell am instrument -w -e class com.vandalsoftware.android.common.IoUtilsTests com.vandalsoftware.android.tests/android.test.InstrumentationTestRunner

License

Apache License, Version 2.0