匹配双打是一件棘手的事情。根据经验,我们学会了使用EPSILON来实现小的双重差异。
JMockit如何处理双重匹配?
例如,当我有以下代码时:
new Expectations() {{
mock.applyWithDouble(4.5);
return 4.0;
mock.applyWithDoubleArray(new Double[] { 4.0, 5.0 });
returns(7.5);
}};
我可以确定JMockit将匹配这些调用吗?
最佳答案
好问题。这是我的方法:
public class DoubleMatchingTest {
static class Dependency {
public double applyWithDouble(double value) { return 0; }
public double applyWithDoubles(double... values) { return 0; }
public double applyWithDoubleArray(Double[] values) { return 0; }
}
@Mocked Dependency mock;
@Test
public void matchDoubles() {
new Expectations() {{
// Match the expected double value within a given tolerance:
mock.applyWithDouble(withEqual(4.5, 0.01));
result = 4.0;
// Argument matchers can be used on the values of a varargs parameter:
mock.applyWithDoubles(withEqual(4.0, 0.1), withEqual(5.0, 0.1));
result = 8.3;
// Matchers cannot be used in arrays, so create/reuse a custom matcher:
mock.applyWithDoubleArray(with(new DoubleArrayMatcher(0.1, 4.0, 5.0)));
result = 7.5;
}};
assertEquals(4.0, mock.applyWithDouble(4.51), 0);
assertEquals(8.3, mock.applyWithDoubles(4.1, 4.9), 0);
assertEquals(7.5, mock.applyWithDoubleArray(new Double[] {4.1, 4.9}), 0);
}
// Reusable custom matcher.
static final class DoubleArrayMatcher implements Delegate<Double[]> {
private final double tolerance;
private final Double[] expected;
DoubleArrayMatcher(double tolerance, Double... expectedValues) {
this.tolerance = tolerance;
expected = expectedValues;
}
@SuppressWarnings("unused")
boolean matches(Double[] actual) {
if (actual == null || actual.length != expected.length) return false;
for (int i = 0; i < actual.length; i++) {
double diff = expected[i] - actual[i];
if (Math.abs(diff) > tolerance) return false;
}
return true;
}
}
}
关于java - JMockit对双数组参数的期望,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/27506180/