Develop Reference

Gradle test fixtures plugin and core module dependencies

I have a project built with Gradle version 6.4 and JDK 8. I'm trying to use the Gradle plugin for Test Fixtures (java-test-fixtures) but I have some issues with the dependencies.
According to the Gradle page linked above, the project should be structured like this:
core-module
-- src
-- main
-- java
-- test
-- java
-- testFixtures
-- java
While the build.gradle.kts file has the following dependencies section:
dependencies {
api("com.my.external.project:1.0")
// ... more API dependencies
testFixturesCompileOnly(project(":core-module"))
testFixturesApi("junit:junit:4.12")
// ... more test dependencies
}
Now, in IntelliJ (the IDE I'm using) classes in the testFixtures/java source folder see the classes in the main/java source folder. So I can add new Java classes under testFixtures/java that have dependencies on those under main.
However, I won't be able to import the dependencies from the external library com.my.external.project:1.0. The problem is confirmed when I try to run the Gradle task compileTestFixturesJava.
I can duplicate the entry in the dependencies section; e.g. I can add:
testFixturesImplementationOnly("com.my.external.project:1.0")
But that is not really what I expect to do; especially when I have dozens of dependencies.
I could also define the dependencies in an array and run a for-each over them. Still, this is not the cleanest solution.
Is there a clean solution that will allow the testFixtures module to use the dependencies declared in the main module?

Most important concept in the Gradle java-test-fixtures plugin is stated in their documentation:
[this plugin] will automatically create a testFixtures source set, in which you can write your test fixtures. Test fixtures are configured so that:
they can see the main source set classes
test sources can see the test fixtures classes
This plugin will indeed create the following dependencies: main <-- testFixtures , and testFixtures <-- test
In your case, testFixtures module should automatically depend on main sources, and also on main dependencies declared in api scope ( com.my.extenal.project:1.0)
See a similar example in a valid sample project here https://github.com/mricciuti/so-64133013 :
Simpsons class has access to Person class from main module
TestHelpers class has access to main dependencies declared in api configuration
Note that testFixtures will not inherit dependencies from the test module: if you need to use such libraries in this module (eg. JUnit, Mockito, ...) you will need to declare explicit dependency , using testFixturesImplementation or testFixturesApi configuration.
See example in core-module
plugins {
id ("java-library")
id ("java-test-fixtures")
}
dependencies {
// Main dependencies
// will be available in "testFixture" as well thanks to "api" configuration
api("org.apache.commons:commons-lang3:3.9")
api(project(":utils-module"))
// Testfixture dependencies
// ==> mockito lib will be available in testFixture module and also in consumer modules (e.g test)
testFixturesApi("org.mockito:mockito-core:3.5.13")
// Test dependencies
// dependencies specific to the "test" module; not visible from "testFixtures"
testImplementation("org.junit.jupiter:junit-jupiter-api:5.3.1")
testRuntimeOnly ("org.junit.jupiter:junit-jupiter-engine:5.3.1")
}

Implement custom modules for checkstyle

I've created a plugin which invokes the Checkstyle plugin for all the sub projects in a project. Executing simple checkstyle rules against any of the projects works fine, but when I introduce my custom Module, the build process throws up
Caused by: com.puppycrawl.tools.checkstyle.api.CheckstyleException: Unable to instantiate 'com.test.gradle.plugin.perf.MethodLimitCheck' class
This class has the custom rule, that I want checkstyle to run. My plugin gets triggered during the build of the project and tries to run this custom module where it fails. Tried going through a lot of online resources but couldn't find anything. I'm using Checkstyle version 8.17.
Why is the other project not able to instantiate the class? Even when the class is a part of the plugin jar, which is attached to the other project ?
What is the correct way to attach a custom module ?

For Gradle, custom checks must be placed on the classpath of the analysis run by adding the custom check to the checkstyle configuration. Example from the Checkstyle Addons library (basically a collection of custom checks):
plugins {
id 'checkstyle' // regular Checkstyle plugin
}
dependencies {
checkstyle group: 'com.thomasjensen.checkstyle.addons', name: 'checkstyle-addons', version: '5.2.2'
}
checkstyle {
configFile file('your-checkstyle.xml')
toolVersion '8.0' // set Checkstyle version here
}

Android studio 3.1 not recognizing jar annotation processing

I'm trying to implement my own annotation processor in my android studio project. All is working well and compiling until I add this simple line to build.gradle dependencies block:
dependencies {
.
.
.
annotationProcessor(':processor')
}
At that point I get this error when compiling:
Could not find :processor:. Required by:
project :app Search in build.gradle files
I've followed endless tutorials and nothing seems to help. I've just recently upgraded to AS 3.1 and thinking maybe it relates?
Here is the project structure: (mind you - here I add the annotation processor as a jar file. I've also attached an image trying to do it as a different module and same result)
Here is a different I'm trying to add it - creating the annotation processor in the same project with a different module and still no go:
Some extra info in pics...
Project structure:
app.build:
processor.build:
annotation:
MainActivity:
Processor implementation:

If you have everything inside the same artifact, — annotation processor, it's annotations and library classes, used by processor users, Android Gradle plugin requires you to declare two dependencies on the same artifact:
annotationProcessor project(':processor')
compile project(':processor')
or
annotationProcessor files('libs/processor.jar')
compile files('libs/processor.jar')
Note, that such setup might become unsupported in future. It is advisable to split your processor in separate module and make it depend on the rest of code. After doing so you will be able to declare dependencies like this:
annotationProcessor project(':processor') // processor-only jar
compile project(':processor-api') // annotations and classes for user code

How to run single Android local unit test using gradle 2.4. Test filtering is not supported

I'm using gradle to build my android project and am not able to run single local unit test. I have several test classes and one of them is MockServerTest and I only want to run test methods in this class.
I tried using gradle -Dtest.single=MockServerTest test but it turned out running all my tests, including these in other test classes.
I also tried gradle test --tests MockServerTest but an error occurred said
Test filtering is not supported for given version of junit. Please upgrade junit version to at least 4.6.
But I'm using junit 4.12 in my gradle file
testCompile 'junit:junit:4.12'
I'm using gradle 2.4 with com.android.tools.build:gradle:1.2.3.
Also, how can I run a single test method inside a single test class?
BTW, I'm able to run single test method inside Android Studio, by right clicking on the test method and select run targetTestMethod() from the menu. But how can I achieve this in the terminal? I guess Android Studio also trigger a certain command to do this. How can I see what that command is?

Figured it out myself. I have to run
gradle testDebug --tests com.my.package.TestClassName
There are two things to note here.
1. You have to use gradle testDebug or gradle testRelease instead of just gradle test. If you have build variant, you have to use gradle testVariantNameDebug or gradle testVariantNameRelease
2. You have to specify the whole qualified class name, means including the package name.

You can use Android Gradle plugin DSL to set up test tasks filters like this:
android {
testOptions {
unitTests.all {
it.testNameIncludePattern = "*.SomeTest"
}
}
}
You can find more information on testOptions here and filters here.

Have you tried running gradle test -Dtest.single=MockServerTest? More information can be found here.

How to make Gradle compile Groovy tests before Java tests

The Groovy plugin for Gradle claims that it "supports joint compilation, which allows to freely mix and match Groovy and Java code, with dependencies in both directions".
However, I don't think this applies to test code.
I have a Java 'sample' test in src/test/java... which uses a class which is located in src/test/groovy.
When trying to build with Gradle, I get an error like this:
SwingJavaFXSampleAppTestInJava.java:23: error: cannot find symbol
SwingJavaFXSampleAppTest swingJavaFx = new SwingJavaFXSampleAppTest();
Notice that SwingJavaFXSampleAppTest is a Groovy class that has not been compiled yet (in the Gradle output I can see that it did not run the compileTestGroovy before it tried compileTestJava because the former depends on the latter).
I am able to build this same project with Maven using the groovy-eclipse plugin.
Why does it not work in Gradle when it claims to support compilation in any order, and how can I make it work?

As explained in the Gradle User Guide, only code passed to GroovyCompile tasks is joint-compiled. So either you put both Java and Groovy code into src/main/groovy, or you reconfigure the source sets:
sourceSets.main.java.srcDirs = []
sourceSets.main.groovy.srcDirs = ["src/main/java", "src/main/groovy"]
For tests, replace all occurrences of main with test.

You should be able to move your java tests into src/test/groovy.