Configure Mockito Java agent in Test tasks

Closes gh-35207

buildSrc/src/main/java/org/springframework/build/TestConventions.java

@@ -16,9 +16,9 @@
 
 package org.springframework.build;
 
-import java.util.Map;
-
 import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.artifacts.Dependency;
 import org.gradle.api.plugins.JavaBasePlugin;
 import org.gradle.api.tasks.testing.Test;
 import org.gradle.api.tasks.testing.TestFrameworkOptions;
@@ -26,12 +26,16 @@ import org.gradle.api.tasks.testing.junitplatform.JUnitPlatformOptions;
 import org.gradle.testretry.TestRetryPlugin;
 import org.gradle.testretry.TestRetryTaskExtension;
 
+import java.util.Map;
+
 /**
  * Conventions that are applied in the presence of the {@link JavaBasePlugin}. When the
  * plugin is applied:
  * <ul>
  * <li>The {@link TestRetryPlugin Test Retry} plugin is applied so that flaky tests
  * are retried 3 times when running on the CI server.
+ * <li>Common test properties are configured
+ * <li>The Mockito Java agent is set on test tasks.
  * </ul>
  *
  * @author Brian Clozel
@@ -45,6 +49,7 @@ class TestConventions {
 	}
 
 	private void configureTestConventions(Project project) {
+		configureMockitoAgent(project);
 		project.getTasks().withType(Test.class,
 				test -> {
 					configureTests(project, test);
@@ -75,6 +80,19 @@ class TestConventions {
 		);
 	}
 
+	private void configureMockitoAgent(Project project) {
+		if (project.hasProperty("mockitoVersion")) {
+			String mockitoVersion = (String) project.getProperties().get("mockitoVersion");
+			Configuration mockitoAgentConfig = project.getConfigurations().create("mockitoAgent");
+			mockitoAgentConfig.setTransitive(false);
+			Dependency mockitoCore = project.getDependencies().create("org.mockito:mockito-core:" + mockitoVersion);
+			mockitoAgentConfig.getDependencies().add(mockitoCore);
+			project.afterEvaluate(p -> {
+				p.getTasks().withType(Test.class, test -> test.jvmArgs("-javaagent:" + mockitoAgentConfig.getAsPath()));
+			});
+		}
+	}
+
 	private void configureTestRetryPlugin(Project project, Test test) {
 		project.getPlugins().withType(TestRetryPlugin.class, testRetryPlugin -> {
 			TestRetryTaskExtension testRetry = test.getExtensions().getByType(TestRetryTaskExtension.class);