package com.googlecode.gwt.test.assertions;
import static java.lang.String.format;
import static org.fest.assertions.error.ShouldBeEqual.shouldBeEqual;
import org.fest.assertions.api.AbstractAssert;
import org.fest.assertions.description.Description;
import org.fest.assertions.error.BasicErrorMessageFactory;
import org.fest.assertions.internal.Failures;
import com.googlecode.gwt.test.utils.GwtReflectionUtils;
/**
* Template for all gwt-test-utils assertions.
*
* @param <S> used to simulate "self types." For more information please read "<a href=
* "http://passion.forco.de/content/emulating-self-types-using-java-generics-simplify-fluent-api-implementation"
* target="_blank">Emulating 'self types' using Java Generics to simplify fluent API
* implementation</a>."
* @param <A> the type of the "actual" value.
*
* @author Gael Lazzari
*
*/
public abstract class GwtGenericAssert<S extends GwtGenericAssert<S, A>, A> extends
AbstractAssert<S, A> {
protected final GwtWritableAssertionInfo gwtInfo;
private final Failures failures = Failures.instance();
/**
* Creates a new <code>{@link GwtGenericAssert}</code>.
*
* @param actual the actual value to verify.
* @param selfType the "self type."
*/
protected GwtGenericAssert(A actual, Class<S> selfType) {
super(actual, selfType);
// hack because fest-assert "info" is not configurable..
gwtInfo = new GwtWritableAssertionInfo();
GwtReflectionUtils.setPrivateFieldValue(this, "info", gwtInfo);
}
/**
* Sets the description of this object.
*
* @param description the new description to set.
* @param args the args used to fill description as in {@link String#format(String, Object...)}.
* @return {@code this} object.
* @throws NullPointerException if the description is {@code null}.
* @see #describedAs(String)
*/
public S as(String description, Object... args) {
return describedAs(format(description, args));
}
/**
* Prefixes the assertion {@link Description} with a raw prefix string.
*
* @param prefix the error message prefix.
* @return this assertion object.
*/
public S withPrefix(String prefix) {
this.gwtInfo.prefix(prefix);
return myself;
}
/**
* Returns a <code>{@link AssertionError}</code> describing an assertion failure. A default
* description is set if the default error message is not overrided and a custom description is
* not applied. In both case, the resulting description would be prefixed by the message
* eventually supplied through {@link GwtGenericAssert#withPrefix(String)}.
*
* @param format the format string.
* @param arguments arguments referenced by the format specifiers in the format string.
*
* @return a {@code AssertionError} describing the assertion failure based on the supplied
* message.
*/
protected AssertionError failWithMessage(String format, Object... arguments) {
GwtWritableAssertionInfo info = new GwtWritableAssertionInfo();
info.prefix(gwtInfo.prefix());
info.overridingErrorMessage(gwtInfo.overridingErrorMessage());
Description d = gwtInfo.superDescription();
String newDescription = d != null ? d.value() : this.actual.getClass().getSimpleName();
info.description(newDescription);
return failures.failure(info, new BasicErrorMessageFactory(format, arguments));
}
/**
* Returns a <code>{@link AssertionError}</code> describing a property comparison failure. A
* default description is set if the default error message is not overrided and a custom
* description is not applied. In both case, the resulting description would be prefixed by the
* message eventually supplied through {@link GwtGenericAssert#withPrefix(String)}.
*
* @param propertyName the compared property name
* @param actual the actual value.
* @param expected the expected value.
* @return a {@code AssertionError} describing the comparison failure.
*/
protected AssertionError propertyComparisonFailed(String propertyName, Object actual,
Object expected) {
GwtWritableAssertionInfo info = new GwtWritableAssertionInfo();
info.prefix(gwtInfo.prefix());
info.overridingErrorMessage(gwtInfo.overridingErrorMessage());
Description d = gwtInfo.superDescription();
String newDescription = d != null ? d.value() + " " + propertyName
: this.actual.getClass().getSimpleName() + "'s " + propertyName;
info.description(newDescription);
return failures.failure(info, shouldBeEqual(actual, expected));
}
}