Autowired applicationContext is null in JUnit 5 - spring

Question

I'm trying to migrate my spring applications to test with JUnit 5. It worked fine with JUnit 4. My problem is that I can't access the application context, it is null, but should be an object. I've included imports etc, in case something is wrong there.
Test:
package com.mycompany.mavenspringjunit5;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
#SpringJUnitConfig(locations = "/test-config.xml")
public class MainTest
{
#Autowired
ApplicationContext applicationContext;
#Autowired
Integer number;
// fails
#Test
public void testGivenAppContext_WhenInjected_ThenItShouldNotBeNull()
{
System.out.println("number: " + number);
Assertions.assertNotNull(applicationContext, "applicationContext should not be null");
}
// works
#Test
public void testDoStuff()
{
ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("/test-config.xml");
Main instance = ctx.getBean(Main.class);
instance.doStuff();
}
}
Main:
package com.mycompany.mavenspringjunit5;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Component;
#Component
public class Main
{
#Autowired
Integer number;
#Autowired
ApplicationContext applicationContext;
public static void main(String[] args)
{
ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
ctx.getBean(Main.class).doStuff();
}
void doStuff()
{
System.out.println("The number is " + number);
System.out.println("applicationContext " + applicationContext);
}
}
pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mycompany</groupId>
<artifactId>MavenSpringJunit5</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<spring.version>5.3.4</spring.version>
</properties>
<dependencies>
<dependency>
<groupId>org.junit.jupiter</groupId>
<artifactId>junit-jupiter</artifactId>
<version>5.8.0-M1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
test-config.xml (in the directory "....\MavenSpringJunit5\src\test\resources\test-config.xml"):
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.3.xsd">
<context:annotation-config />
<context:component-scan base-package="com.mycompany.mavenspringjunit5"/>
<bean id="number" class="java.lang.Integer">
<constructor-arg value="42" />
</bean>
</beans>
Output:
-------------------------------------------------------
T E S T S
-------------------------------------------------------
Running com.mycompany.mavenspringjunit5.MainTest
The number is 42
applicationContext org.springframework.context.support.ClassPathXmlApplicationContext#51521cc1, started on Mon Feb 22 10:49:15 CET 2021
number: null
Tests run: 2, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.884 sec <<< FAILURE!
com.mycompany.mavenspringjunit5.MainTest.testGivenAppContext_WhenInjected_ThenItShouldNotBeNull() Time elapsed: 0.009 sec <<< FAILURE!
org.opentest4j.AssertionFailedError: applicationContext should not be null ==> expected: not <null>
at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:39)
at org.junit.jupiter.api.Assertions.fail(Assertions.java:118)
at org.junit.jupiter.api.AssertNotNull.failNull(AssertNotNull.java:47)
at org.junit.jupiter.api.AssertNotNull.assertNotNull(AssertNotNull.java:36)
at org.junit.jupiter.api.Assertions.assertNotNull(Assertions.java:292)
at com.mycompany.mavenspringjunit5.MainTest.testGivenAppContext_WhenInjected_ThenItShouldNotBeNull(MainTest.java:24)

Answer 1

Tested it and tests run fine in my IDE (Intellij) running the same with your provided pom.xml fails.
You need to upgrade the maven-surefire-plugin to properly detect and execute the classes.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.2</version>
</plugin>
</plugins>
</build>
This is also expressed in the Junit5 documentation.