Added failing tests for BeforeTry member variables

api/src/main/java/net/jqwik/api/lifecycle/BeforeTry.java

@@ -7,10 +7,11 @@
 import static org.apiguardian.api.API.Status.*;
 
 /**
- * Annotate methods of a container class with {@code @BeforeTry}
- * to have them run once before each try - the actual invocation of the property
+ * Annotate methods or member variables of a container class with {@code @BeforeTry}.
+ * Annotated methods will then be run once before each try - the actual invocation of the property
  * method with generated parameters - including properties of
  * embedded containers.
+ * Annotated members will be freshly initialized before each try.
  *
  * <p>{@code @BeforeTry} methods are inherited from superclasses
  * and implemented interfaces as long as they are not <em>hidden</em>
@@ -28,7 +29,7 @@
  *
  * @see AfterTry
  */
-@Target({ElementType.ANNOTATION_TYPE, ElementType.METHOD})
+@Target({ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 @API(status = MAINTAINED, since = "1.4.0")
 public @interface BeforeTry {

engine/src/main/java/net/jqwik/engine/hooks/Hooks.java

@@ -24,6 +24,9 @@ public static class AroundProperty {
 	public static class AroundTry {
 		// Should run close to property method
 		public static final int TRY_LIFECYCLE_METHODS_PROXIMITY = -10;
+
+		// Should run first thing
+		public static final int BEFORE_TRY_MEMBERS_PROXIMITY = -100;
 	}
 
 }

engine/src/main/java/net/jqwik/engine/hooks/lifecycle/BeforeTryMembersHook.java

@@ -0,0 +1,63 @@
+package net.jqwik.engine.hooks.lifecycle;
+
+import java.lang.reflect.*;
+import java.util.*;
+
+import org.junit.platform.engine.support.hierarchical.*;
+
+import net.jqwik.api.lifecycle.*;
+import net.jqwik.engine.hooks.*;
+import net.jqwik.engine.support.*;
+
+public class BeforeTryMembersHook implements AroundTryHook {
+
+	private void beforeTry(TryLifecycleContext context) {
+		System.out.println("initialize before try members");
+		// List<Method> beforeTryMethods = LifecycleMethods.findBeforeTryMethods(context.containerClass());
+		// callTryMethods(beforeTryMethods, context);
+	}
+
+	private void callTryMethods(List<Method> methods, TryLifecycleContext context) {
+		Object testInstance = context.testInstance();
+		ThrowableCollector throwableCollector = new ThrowableCollector(ignore -> false);
+		for (Method method : methods) {
+			Object[] parameters = MethodParameterResolver.resolveParameters(method, context);
+			throwableCollector.execute(() -> callMethod(method, testInstance, parameters));
+		}
+		throwableCollector.assertEmpty();
+	}
+
+	private void callMethod(Method method, Object target, Object[] parameters) {
+		JqwikReflectionSupport.invokeMethodPotentiallyOuter(method, target, parameters);
+	}
+
+	private void afterTry(TryLifecycleContext context) {
+		List<Method> afterTryMethods = LifecycleMethods.findAfterTryMethods(context.containerClass());
+		callTryMethods(afterTryMethods, context);
+	}
+
+	@Override
+	public PropagationMode propagateTo() {
+		return PropagationMode.ALL_DESCENDANTS;
+	}
+
+	@Override
+	public boolean appliesTo(Optional<AnnotatedElement> element) {
+		return element.map(e -> e instanceof Method).orElse(false);
+	}
+
+	@Override
+	public int aroundTryProximity() {
+		return Hooks.AroundTry.BEFORE_TRY_MEMBERS_PROXIMITY;
+	}
+
+	@Override
+	public TryExecutionResult aroundTry(TryLifecycleContext context, TryExecutor aTry, List<Object> parameters) {
+		beforeTry(context);
+		try {
+			return aTry.execute(parameters);
+		} finally {
+			afterTry(context);
+		}
+	}
+}

engine/src/main/resources/META-INF/services/net.jqwik.api.lifecycle.LifecycleHook

@@ -2,6 +2,7 @@ net.jqwik.engine.hooks.lifecycle.AutoCloseableHook
 net.jqwik.engine.hooks.lifecycle.ContainerLifecycleMethodsHook
 net.jqwik.engine.hooks.lifecycle.PropertyLifecycleMethodsHook
 net.jqwik.engine.hooks.lifecycle.TryLifecycleMethodsHook
+net.jqwik.engine.hooks.lifecycle.BeforeTryMembersHook
 net.jqwik.engine.hooks.DisabledHook
 net.jqwik.engine.hooks.statistics.StatisticsHook
 net.jqwik.engine.hooks.ResolveReporterHook

engine/src/test/java/net/jqwik/engine/execution/lifecycle/BeforeTryOnMemberVariableTests.java

@@ -0,0 +1,44 @@
+package net.jqwik.engine.execution.lifecycle;
+
+import org.assertj.core.api.*;
+
+import net.jqwik.api.*;
+import net.jqwik.api.constraints.*;
+import net.jqwik.api.lifecycle.*;
+
+class BeforeTryOnMemberVariableTests {
+
+	@BeforeTry
+	private int member = 41;
+
+	@BeforeTry
+	void testBefore() {
+		System.out.println("before try outer");
+	}
+
+	@Property(tries = 10)
+	void beforeTryOnMember(@ForAll @IntRange(min = 1, max = 100) int addend) {
+		Assertions.assertThat(member).isEqualTo(41);
+		member = member + addend;
+	}
+
+	@Group
+	class InnerTests {
+
+		@BeforeTry
+		private int innerMember = 42;
+
+		@BeforeTry
+		void testBeforeInner() {
+			System.out.println("before try inner");
+		}
+
+		@Property(tries = 10)
+		void beforeTryOnMemberInInnerGroup(@ForAll @IntRange(min = 1, max = 100) int addend) {
+			Assertions.assertThat(member).isEqualTo(41);
+			member = member + addend;
+			Assertions.assertThat(innerMember).isEqualTo(42);
+			innerMember = innerMember + addend;
+		}
+	}
+}