Unit Tests

For a developer, writing test cases is vital. In Twister2 development with bazel build, here is how to setup a test package in your module.

NOTE

The task API test bench is already created. So try it for a different module or your own module.

Let's take an example of creating a test bench for task api.

The package for this is twister2/task

Step 1

Create a tests folder called test within the module that you want to create the tests.

Step 2

Within the tests folder create a folder called java.

Step 3

Inside java folder, create a BUILD (a textfile) file

Step 4

In the same level of BUILD file, create another folder with the expected package name for including test classes.

Step 5

Create any necessary sub packages and include java classes for tests.

After completing Step 1 to 5, for instance the following folder structure will be an example output.

twister2/task
├── src
└── tests
    └── java
        ├── BUILD
        └── edu.iu.dsc.tws.task
            └── test
                └── Hello.java

Step 6

Adding content BUILD file. Depending on the module, pick the relevant dependencies to fit in the bazel build file and include these additional dependencies to support Junit testing.

        "//third_party/java:junit4",
        "//third_party/java:mockito",
        "//third_party/java:powermock",

Step 7

Create a test class called "Hello.java" (without quotes). Then add the test classes in the build as follows.

package edu.iu.dsc.tws.task.test;

import org.junit.Test;

public class Hello {

  @Test
  public void hello() {
    System.out.println("Hello Task");
  }

}

java_tests(
    test_classes = [
        "edu.iu.dsc.tws.task.test.Hello",
    ],
    runtime_deps = [
        ":task-tests",
    ],
)

Overall BUILD file should take the following shape. (Dependencies can be dependable on what module you're working on)

load("//tools:rules/java_tests.bzl", "java_tests")

java_library(
    name = "task-tests",
    srcs = glob(["**/*.java"]),
    deps = [
        "//third_party:ompi_javabinding_java",
        "//third_party/java:junit4",
        "//third_party/java:mockito",
        "//third_party/java:powermock",
        "//twister2/common/src/java:common-java",
        "//twister2/comms/src/java:comms-java",
        "//twister2/data/src/main/java:data-java",
        "@com_esotericsoftware_kryo//jar",
        "@com_google_guava_guava//jar",
        "@org_apache_commons_commons_lang3//jar",
        "@org_yaml_snakeyaml//jar",
    ],
)

java_tests(
    test_classes = [
        "edu.iu.dsc.tws.task.test.Hello",
    ],
    runtime_deps = [
        ":task-tests",
    ],
)

Step 8

Set up this for the IDE. For supporting Intellij IDEA, you need to run the following script within the twister2 cloned project.

./scripts/setup-intellij.sh

This will create and make the test bench compatible with the IDE. After the initial setup, you can add test classes the same way you're doing it.

You're all set to do unit testing.

Running Unit Tests

As Bazel is our build tool, this is how to run the tests.

You can specify your test class and run it quite easily as same as you do with Maven. For now IntelliJ doesn't have a inbuilt Bazel unit testing support.

bazel test --config=ubuntu twister2/task/tests/java:Hello

It will give a sample output like this

INFO: Build completed successfully, 4 total actions
//twister2/task/tests/java:Hello                                         PASSED in 0.3s

Executed 1 out of 1 test: 1 test passes.
INFO: Build completed successfully, 4 total actions
← FAQContributing →