Passing additional arguments to tests with ScalaTest - scala

Question

Currently I'm using IntelliJ Idea 15 and Scalatest framework to make some unit tests. And I need to pass my own arguments into test and somehow read them from code. For instance:
Suppose I have such class
class Test extends FunSuite {
test("Some test") {
val arg = // here I want to get an argument which I want to pass. Something like args("arg_name")
println(arg)
assert(2 == 2)
}
}
And to run the test with argument I want to do something like
test -arg_name=blabla
So, the question is how to pass this an argument and how to obtain it.

Answer 1

I found interesting trait BeforeAndAfterAllConfigMap. This one has beforeAll method with a parameter configMap: ConfigMap. So here is my solution:
class Test extends FunSuite with BeforeAndAfterAllConfigMap {
override def beforeAll(configMap: ConfigMap) = {
//here will be some stuff and all args are available in configMap
}
test("Some test") {
val arg = // here I want to get an argument which I want to pass. Something like args("arg_name")
println(arg)
assert(2 == 2)
}
}

Answer 2

In scalatest, we can use configMap to pass command parameters.
There is an example with using configMap:
import org.scalatest.{ConfigMap, fixture}
class TestSuite extends fixture.Suite with fixture.ConfigMapFixture{
def testConfigMap(configMap: Map[String, Any]) {
println(configMap.get("foo"))
assert(configMap.get("foo").isDefined)
}
}
object Test {
def main(args: Array[String]): Unit = {
(new TestSuite).execute(configMap = ConfigMap.apply(("foo","bar")))
}
}
also we can run test with command line parameters:
scala -classpath scalatest-<version>.jar org.scalatest.tools.Runner -R compiled_tests -Dfoo=bar
scalatest runner
ConfigMapFixture Test

Answer 3

I found BeforeAndAfterAllConfigMap incorporates into existing scalatest easily if you have already using FunSpec, FunSuite or FlatSpec. all you have to do is import & extend your test with BeforeAndAfterAllConfigMap.
One of the ways you can pass argument to scalatest is:
Pass the argument from command line as either
system or project property
In build.gradle file retrieve the [system|project] property
Pass property retrieved in step 2 to
test runtime.
Here is a complete example in FlatSpec but easily applicable in FunSuite as well:
package com.passarg.test
import org.scalatest.{BeforeAndAfterAllConfigMap, ConfigMap, FlatSpec}
class PassArgsToScala extends FlatSpec with BeforeAndAfterAllConfigMap {
var foo = ""
override def beforeAll(configMap: ConfigMap) = {
// foo=bar is expected to be passed as argument
if (configMap.get("foo").isDefined) {
foo = configMap.get("foo").fold("")(_.toString)
}
println("foo=" + foo)
}
"Arg passed" must "be bar" in {
assert(foo === "bar")
info("passing arg seem to work ==> " + "foo=" + foo)
}
}
build.gradle
apply plugin: 'scala'
repositories {
mavenCentral()
}
dependencies {
compile 'org.scala-lang:scala-library:2.11.8'
testCompile 'org.scalatest:scalatest_2.11:3.0.0'
}
task spec(dependsOn: ['testClasses']) {
javaexec {
main = 'org.scalatest.tools.Runner'
args = ['-R', 'build/classes/test', '-o']
args += '-m'
args += 'com.passarg.test'
if (project.hasProperty("foo")) {
args += "-Dfoo=" + project.foo
}
classpath = sourceSets.test.runtimeClasspath
}
}
Running the test from command-line:
./gradlew -q spec -Pfoo=bar
Result:
$ ./gradlew -q spec -Pfoo=bar
...
Run starting. Expected test count is: 1
PassArgsToScala:
Arg passed
- must be bar
+ passing arg seem to work ==> foo=bar

Answer 4

I recently had to pass a feature flag to scalatest tests so I could test two implementations of the same API. I used an environment variable for this. It works for sbt & maven. The content of the variable will end up in the configMap. How to deal with the configMap you can check at other posts (or at the post I base this answer on).
You can pass the argument "ABC" as follows:
FEATURE_FLAG="ABC" sbt test
# or
FEATURE_FLAG="ABC" mvn test
sbt setup:
// build.sbt
val featureFlagArg = sys.env.get("FEATURE_FLAG")
.map(ff => s"-DfeatureFlag=$ff")
.map(Tests.Argument(TestFrameworks.ScalaTest, _))
Test / testOptions ++= featureFlagArg
maven setup (using the scalatest maven plugin):
<!-- pom.xml -->
<!-- ... -->
<plugin>
<groupId>org.scalatest</groupId>
<artifactId>scalatest-maven-plugin</artifactId>
<version>1.0</version>
<configuration>
<config>featureFlag=${env.FEATURE_FLAG}</config>
</configuration>
<executions>
<execution>
<id>test</id>
<goals>
<goal>test</goal>
</goals>
</execution>
</executions>
</plugin>
<!-- ... -->