Provide a session test framework for JUnit 5

A first draft for realizing session tests with JUnit 5.

It uses an extension that intercepts test methods calls to start a
separate Eclipse session in which the tests are executed. The results
are evaluated in the intercepted method execution in way they were
evaluated for existing JUnit-3-based session tests.

Functionality is demonstrated in a manually executed sample session test
as well as by application to the session test in the runtime tests
project.

runtime/tests/org.eclipse.core.tests.harness/META-INF/MANIFEST.MF

@@ -5,22 +5,35 @@ Bundle-SymbolicName: org.eclipse.core.tests.harness;singleton:=true
 Bundle-Version: 3.15.300.qualifier
 Bundle-Vendor: Eclipse.org
 Export-Package: org.eclipse.core.tests.harness;version="2.0",
+ org.eclipse.core.tests.harness.session,
  org.eclipse.core.tests.session;version="2.0"
 Require-Bundle: org.junit,
  org.eclipse.test.performance,
  org.eclipse.core.runtime;bundle-version="[3.29.0,4.0.0)",
  org.eclipse.jdt.junit.runtime,
  org.eclipse.jdt.junit4.runtime,
- org.eclipse.pde.junit.runtime
+ org.eclipse.jdt.junit5.runtime,
+ org.eclipse.pde.junit.runtime,
+ junit-platform-launcher,
+ junit-platform-engine,
+ junit-jupiter-engine,
+ junit-vintage-engine,
+ junit-platform-suite-commons,
+ junit-platform-suite-engine
 Bundle-ActivationPolicy: lazy
 Bundle-RequiredExecutionEnvironment: JavaSE-17
 Import-Package: javax.xml.parsers,
  net.bytebuddy,
  org.apiguardian.api,
  org.assertj.core.api,
  org.junit.jupiter.api,
- org.junit.platform.suite.api,
+ org.junit.jupiter.api.condition,
+ org.junit.jupiter.api.extension,
+ org.junit.jupiter.migrationsupport,
+ org.junit.jupiter.params,
  org.junit.platform.commons,
+ org.junit.platform.runner,
+ org.junit.platform.suite.api,
  org.opentest4j,
  org.w3c.dom,
  org.xml.sax

runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/SessionShouldError.java

@@ -0,0 +1,27 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Vector Informatik GmbH and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.core.tests.harness.session;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates that a session of a test case is expected to terminate with a
+ * failure or error. To be used in combination with a
+ * {@link SessionTestExtension}.
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface SessionShouldError {
+	// Marker annotation
+}