testgen : Scala unit test template generator

Overview

The default template is "FunSuite with ShouldMatchers", but it's also possible to specify other templates, such as ScalaTest or specs/specs2.

Class

package com.example
case class Name(first: String, last: String)

When you run "testgen" via sbt:

$ sbt
> testgen com.example.Name
"com.example.NameSuite" created.

the following code will be generated:

package com.example

import org.scalatest._
import org.scalatest.matchers._
import org.junit.runner.RunWith
import org.scalatest.junit.JUnitRunner

@RunWith(classOf[JUnitRunner])
class NameSuite extends FunSuite with ShouldMatchers {

  type ? = this.type // for IntelliJ IDEA

  test("available") {
    val first: String = ""
    val last: String = ""
    val instance = new Name(first,last)
    instance should not be null
  }

}

Also for classes which import other types:

package com.example
import entity.Bean
class BeanHolder(val bean: Bean) extends AbstractHolder

Run "testgen":

$ sbt
> testgen com.example.BeanHolder
"com.example.BeanHolderSpec" created.

"entity.Bean" will be imported in the generated test:

package com.example

import org.scalatest._
import org.scalatest.matchers._
import org.junit.runner.RunWith
import org.scalatest.junit.JUnitRunner
import entity.Bean

@RunWith(classOf[JUnitRunner])
class BeanHolderSpec extends FlatSpec with MustMatchers {

  type ? = this.type // for IntelliJ IDEA

  "BeanHolder" should "be available" in {
    val bean: Bean = null
    val instance = new BeanHolder(bean)
    instance must not be null
  }

}

Following is an example with specs/specs2:

@RunWith(classOf[JUnitRunner])
class BeanHolderSpec extends Specification {

  "BeanHolder" should {
    "be available" in {
      val instance = new Sample()
      instance must notBeNull
      // (specs2) instance must not beNull 
    }
  }
 
}

Object

package com.example
object Util

Run "testgen" via sbt:

$ sbt
> testgen com.example.Util
"com.example.UtilSuite" created.

The following code will be generated:

package com.example

import org.scalatest._
import org.scalatest.matchers._
import org.junit.runner.RunWith
import org.scalatest.junit.JUnitRunner

@RunWith(classOf[JUnitRunner])
class UtilSuite extends FunSuite with ShouldMatchers {

  type ? = this.type // for IntelliJ IDEA

  test("available") {
    Util.isInstanceOf[Singleton] should equal(true)
  }

}

Trait

package com.example
trait Writable

Run "testgen" via sbt:

$ sbt
> testgen com.example.Writable
"com.example.WritableSuite" created.

The following code will be generated:

package com.example

import org.scalatest._
import org.scalatest.matchers._
import org.junit.runner.RunWith
import org.scalatest.junit.JUnitRunner

@RunWith(classOf[JUnitRunner])
class WritableSuite extends FunSuite with ShouldMatchers {

  type ? = this.type // for IntelliJ IDEA

  test("available") {
    val mixedin = new Object with Writable
    mixedin should not be null
  }

}

Usage with sbt

mkdir -p project/plugins

Create the directory if it doesn't yet exist.

put project/plugins/plugins.sbt

Edit project/plugins/plugins.sbt as follows:

scalaVersion := "2.8.1"

resolvers ++= Seq(
  "seratch.github.com releases"  at "http://seratch.github.com/mvn-repo/releases",
  "seratch.github.com snapshots" at "http://seratch.github.com/mvn-repo/snapshots"
)

libraryDependencies ++= Seq(
  "com.github.seratch" %% "testgen-sbt" % "0.1-SNAPSHOT"
)

Run sbt

xsbt 0.10.x

"testgen" requires xsbt 0.10.x (sorry, sbt 0.7.x is not supported).

See also: https://github.com/harrah/xsbt/wiki/Setup

Specify a filename

src/main/scala/com/example/models.scala:

package com.example
case class Staff(id: Long, name: String, ...)
case class Company(id: Long, name: String, ...)
case class Stock(id: Long, itemId: Long, ...)

And specify the above file:

$ sbt
> testgen src/main/scala/com/example/models.scala
"com.example.StaffSuite" already exists.
"com.example.CompanySuite" already exists.
"com.example.StockSuite" created.

"src/main/scala" is omissible.

$ sbt
> testgen com/example/models.scala

Specify a class name

If you specify a class name, it must be the name of the source file.

"com.example.MyApp" will be translated as "src/main/scala/com/example/MyApp.scala".

$ sbt
> testgen com.example.MyApp
"com.example.MyAppSuite" created.

Specify a directory

"testgen" will search targets recursively under the directory.

$ sbt
> testgen src/main/scala/com/example

Specify a package name

The same as specifying a directory.

$ sbt
> testgen com.example
"com.example.MyAppSuite" created.
"com.example.util.MyUtilSuite" created.

Configuration

Currently configurable using system properties.

java -jar sbt-launch.jar \
  -Dtestgen.srcDir=src/main/scala \
  -Dtestgen.srcTestDir=src/test/scala \
  -Dtestgen.encoding=UTF-8 \
  -Dtestgen.testTemplate=scalatest.FunSuite \
  -Dtestgen.scalagtest.Matchers=ShouldMatchers

Configuration: "testgen.testTemplate"

• "scalatest.FunSuite" : default
• "scalatest.Assertions"
• "scalatest.Spec"
• "scalatest.WordSpec"
• "scalatest.FlatSpec"
• "scalatest.FeatureSpec"
• "specs.Specification"
• "specs2.Specification"

Configuration: "testgen.scalatest.Matchers"

• "ShouldMatchers" : default
• "MustMatchers"
• "" (empty string)

Usage with maven

pom.xml

    <pluginRepositories>
      <pluginRepository>
        <id>seratch.github.com releases</id>
        <name>seratch.github.com releases</name>
        <url>http://seratch.github.com/mvn-repo/releases</url>
      </pluginRepository>
      <pluginRepository>
        <id>seratch.github.com snapshots</id>
        <name>seratch.github.com snapshots</name>
        <url>http://seratch.github.com/mvn-repo/snapshots</url>
      </pluginRepository>
    </pluginRepositories>

    <build>
      <plugins>
        <plugin>
          <groupId>com.github.seratch</groupId>
          <artifactId>maven-testgen-plugin</artifactId>
          <version>0.1-SNAPSHOT</version>
          <!-- If you need
          <configuration>
            <srcDir>src/main/scala</srcDir>
            <srcTestDir>src/test/scala</srcTestDir>
            <encoding>UTF-8</encoding>
            <testTemplate>scalatest.FunSuite</testTemplate>
            <scalatest_Matchers>ShouldMatchers</scalatest_Matchers>
          </configuration>
          -->
        </plugin>
      </plugins>
    </build>

Run "testgen" goal

The rule to specify targets is the same as with the sbt plugin.

maven testgen:run -Dtarget=com.exmaple.MyApp

Happy Testing! :)