Resurrect ClasspathScanningSupport and deprecate it

Because jqwik and mainrunner are using it.

@sormuras @jlink Please update your engines! 😉

Author: marcphilipp

junit-platform-engine/src/main/java/org/junit/platform/engine/support/filter/ClasspathScanningSupport.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2015-2019 the original author or authors.
+ *
+ * All rights reserved. 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-v20.html
+ */
+
+package org.junit.platform.engine.support.filter;
+
+import static org.apiguardian.api.API.Status.DEPRECATED;
+import static org.junit.platform.engine.Filter.composeFilters;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Predicate;
+
+import org.apiguardian.api.API;
+import org.junit.platform.commons.util.ClassFilter;
+import org.junit.platform.engine.DiscoveryFilter;
+import org.junit.platform.engine.EngineDiscoveryRequest;
+import org.junit.platform.engine.discovery.ClassNameFilter;
+import org.junit.platform.engine.discovery.PackageNameFilter;
+
+/**
+ * Support utility methods for classpath scanning.
+ *
+ * @since 1.0
+ * @deprecated Please use {@link org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver}
+ */
+@Deprecated
+@API(status = DEPRECATED, since = "1.5")
+public final class ClasspathScanningSupport {
+
+	private ClasspathScanningSupport() {
+		/* no-op */
+	}
+
+	/**
+	 * Build a {@link Predicate} for fully qualified class names to be used for
+	 * classpath scanning from an {@link EngineDiscoveryRequest}.
+	 *
+	 * @param request the request to build a predicate from
+	 * @deprecated Please use {@link org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver}
+	 */
+	@Deprecated
+	public static Predicate<String> buildClassNamePredicate(EngineDiscoveryRequest request) {
+		List<DiscoveryFilter<String>> filters = new ArrayList<>();
+		filters.addAll(request.getFiltersByType(ClassNameFilter.class));
+		filters.addAll(request.getFiltersByType(PackageNameFilter.class));
+		return composeFilters(filters).toPredicate();
+	}
+
+	/**
+	 * Build a {@link ClassFilter} by combining the name predicate built by
+	 * {@link #buildClassNamePredicate(EngineDiscoveryRequest)} and the passed-in
+	 * class predicate.
+	 *
+	 * @param request the request to build a name predicate from
+	 * @param classPredicate the class predicate
+	 * @deprecated Please use {@link org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver}
+	 */
+	@Deprecated
+	public static ClassFilter buildClassFilter(EngineDiscoveryRequest request, Predicate<Class<?>> classPredicate) {
+		return ClassFilter.of(buildClassNamePredicate(request), classPredicate);
+	}
+
+}

junit-platform-engine/src/main/java/org/junit/platform/engine/support/filter/package-info.java

@@ -0,0 +1,6 @@
+/**
+ * {@link org.junit.platform.engine.Filter}-related support classes intended to be
+ * used by test engine implementations.
+ */
+
+package org.junit.platform.engine.support.filter;