Source code
package org.junit.experimental.theories;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.List;
import org.junit.Assert;
import org.junit.Assume;
import org.junit.experimental.theories.internal.Assignments;
import org.junit.experimental.theories.internal.ParameterizedAssertionError;
import org.junit.internal.AssumptionViolatedException;
import org.junit.runners.BlockJUnit4ClassRunner;
import org.junit.runners.model.FrameworkMethod;
import org.junit.runners.model.InitializationError;
import org.junit.runners.model.Statement;
import org.junit.runners.model.TestClass;
public class Theories extends BlockJUnit4ClassRunner {
public Theories(Class<?> klass) throws InitializationError {
super(klass);
}
@Override
protected void collectInitializationErrors(List<Throwable> errors) {
super.collectInitializationErrors(errors);
validateDataPointFields(errors);
validateDataPointMethods(errors);
}
private void validateDataPointFields(List<Throwable> errors) {
Field[] fields = getTestClass().getJavaClass().getDeclaredFields();
for (Field field : fields) {
if (field.getAnnotation(DataPoint.class) == null && field.getAnnotation(DataPoints.class) == null) {
continue;
}
if (!Modifier.isStatic(field.getModifiers())) {
errors.add(new Error("DataPoint field " + field.getName() + " must be static"));
}
if (!Modifier.isPublic(field.getModifiers())) {
errors.add(new Error("DataPoint field " + field.getName() + " must be public"));
}
}
}
private void validateDataPointMethods(List<Throwable> errors) {
Method[] methods = getTestClass().getJavaClass().getDeclaredMethods();
for (Method method : methods) {
if (method.getAnnotation(DataPoint.class) == null && method.getAnnotation(DataPoints.class) == null) {
continue;
}
if (!Modifier.isStatic(method.getModifiers())) {
errors.add(new Error("DataPoint method " + method.getName() + " must be static"));
}
if (!Modifier.isPublic(method.getModifiers())) {
errors.add(new Error("DataPoint method " + method.getName() + " must be public"));
}
}
}
@Override
protected void validateConstructor(List<Throwable> errors) {
validateOnlyOneConstructor(errors);
}
@Override
protected void validateTestMethods(List<Throwable> errors) {
for (FrameworkMethod each : computeTestMethods()) {
if (each.getAnnotation(Theory.class) != null) {
each.validatePublicVoid(false, errors);
each.validateNoTypeParametersOnArgs(errors);
} else {
each.validatePublicVoidNoArg(false, errors);
}
for (ParameterSignature signature : ParameterSignature.signatures(each.getMethod())) {
ParametersSuppliedBy annotation = signature.findDeepAnnotation(ParametersSuppliedBy.class);
if (annotation != null) {
validateParameterSupplier(annotation.value(), errors);
}
}
}
}
private void validateParameterSupplier(Class<? extends ParameterSupplier> supplierClass, List<Throwable> errors) {
Constructor<?>[] constructors = supplierClass.getConstructors();
if (constructors.length != 1) {
errors.add(new Error("ParameterSupplier " + supplierClass.getName() +
" must have only one constructor (either empty or taking only a TestClass)"));
} else {
Class<?>[] paramTypes = constructors[0].getParameterTypes();
if (!(paramTypes.length == 0) && !paramTypes[0].equals(TestClass.class)) {
errors.add(new Error("ParameterSupplier " + supplierClass.getName() +
" constructor must take either nothing or a single TestClass instance"));
}
}
}
@Override
protected List<FrameworkMethod> computeTestMethods() {
List<FrameworkMethod> testMethods = new ArrayList<FrameworkMethod>(super.computeTestMethods());
List<FrameworkMethod> theoryMethods = getTestClass().getAnnotatedMethods(Theory.class);
testMethods.removeAll(theoryMethods);
testMethods.addAll(theoryMethods);
return testMethods;
}
@Override
public Statement methodBlock(final FrameworkMethod method) {
return new TheoryAnchor(method, getTestClass());
}
public static class TheoryAnchor extends Statement {
private int successes = 0;
private FrameworkMethod fTestMethod;
private TestClass fTestClass;
private List<AssumptionViolatedException> fInvalidParameters = new ArrayList<AssumptionViolatedException>();
public TheoryAnchor(FrameworkMethod method, TestClass testClass) {
fTestMethod = method;
fTestClass = testClass;
}
private TestClass getTestClass() {
return fTestClass;
}
@Override
public void evaluate() throws Throwable {
runWithAssignment(Assignments.allUnassigned(
fTestMethod.getMethod(), getTestClass()));
//if this test method is not annotated with Theory, then no successes is a valid case
boolean hasTheoryAnnotation = fTestMethod.getAnnotation(Theory.class) != null;
if (successes == 0 && hasTheoryAnnotation) {
Assert
.fail("Never found parameters that satisfied method assumptions. Violated assumptions: "
+ fInvalidParameters);
}
}
protected void runWithAssignment(Assignments parameterAssignment)
throws Throwable {
if (!parameterAssignment.isComplete()) {
runWithIncompleteAssignment(parameterAssignment);
} else {
runWithCompleteAssignment(parameterAssignment);
}
}
protected void runWithIncompleteAssignment(Assignments incomplete)
throws Throwable {
for (PotentialAssignment source : incomplete
.potentialsForNextUnassigned()) {
runWithAssignment(incomplete.assignNext(source));
}
}
protected void runWithCompleteAssignment(final Assignments complete)
throws Throwable {
new BlockJUnit4ClassRunner(getTestClass().getJavaClass()) {
@Override
protected void collectInitializationErrors(
List<Throwable> errors) {
// do nothing
}
@Override
public Statement methodBlock(FrameworkMethod method) {
final Statement statement = super.methodBlock(method);
return new Statement() {
@Override
public void evaluate() throws Throwable {
try {
statement.evaluate();
handleDataPointSuccess();
} catch (AssumptionViolatedException e) {
handleAssumptionViolation(e);
} catch (Throwable e) {
reportParameterizedError(e, complete
.getArgumentStrings(nullsOk()));
}
}
};
}
@Override
protected Statement methodInvoker(FrameworkMethod method, Object test) {
return methodCompletesWithParameters(method, complete, test);
}
@Override
public Object createTest() throws Exception {
Object[] params = complete.getConstructorArguments();
if (!nullsOk()) {
Assume.assumeNotNull(params);
}
return getTestClass().getOnlyConstructor().newInstance(params);
}
}.methodBlock(fTestMethod).evaluate();
}
private Statement methodCompletesWithParameters(
final FrameworkMethod method, final Assignments complete, final Object freshInstance) {
return new Statement() {
@Override
public void evaluate() throws Throwable {
final Object[] values = complete.getMethodArguments();
if (!nullsOk()) {
Assume.assumeNotNull(values);
}
method.invokeExplosively(freshInstance, values);
}
};
}
protected void handleAssumptionViolation(AssumptionViolatedException e) {
fInvalidParameters.add(e);
}
protected void reportParameterizedError(Throwable e, Object... params)
throws Throwable {
if (params.length == 0) {
throw e;
}
throw new ParameterizedAssertionError(e, fTestMethod.getName(),
params);
}
private boolean nullsOk() {
Theory annotation = fTestMethod.getMethod().getAnnotation(
Theory.class);
if (annotation == null) {
return false;
}
return annotation.nullsAccepted();
}
protected void handleDataPointSuccess() {
successes++;
}
}
}