public void ReusableConstraintsTest()
{
ReusableConstraint myConstraintNotNull = Is.Not.Null;
ReusableConstraint myConstraintNotEmpty = Is.Not.Empty;
ReusableConstraint myConstraint = myConstraintNotNull.Resolve() & myConstraintNotEmpty.Resolve();
Assert.That("Not a null and empty", myConstraint);
}
void Run(string testSuiteLabel, string testCaseName, IATestCase <T, F> testCase, ReusableConstraint expectedConstraint)
{
TestTools.Log(testCaseName + ":", writeLine: false);
var testCaseLabel = $"{testSuiteLabel}, testCase={testCaseName}";
var resolvedConstraint = expectedConstraint.Resolve();
if (resolvedConstraint is SkipTestConstraint)
{
TestTools.Log(resolvedConstraint);
return;
}
var instance = field.IsStatic ? default : CloneInstancePrototype <T>(instanceType);
var origValue = GetOrigValue(field);
var expectedExceptionType = TestTools.ThrowsConstraintExceptionType(resolvedConstraint);
ConstraintResult constraintResult;
if (expectedExceptionType is null || expectedExceptionType == typeof(IncompatibleFieldTypeException))
{
constraintResult = TestTools.AssertThat(() =>
{
Assert.AreNotEqual(origValue, testValue, "{0}: expected !Equals(origValue, testValue) (indicates static field didn't get reset properly)", testCaseLabel);
var value = testCase.Get(ref instance);
// The ?.ToString() is a trick to ensure that value is fully evaluated from the ref value.
_ = value?.ToString();
Assert.AreEqual(TryConvert(origValue), value, "{0}: expected Equals(origValue, value)", testCaseLabel);
testCase.Set(ref instance, testValue);
var newValue = field.GetValue(instance);
Assert.AreEqual(testValue, TryConvert(newValue), "{0}: expected Equals(testValue, field.GetValue(instance))", testCaseLabel);
TestTools.Log($"{field.Name}: {origValue} => {testCase.Get(ref instance)}");
testCase.Set(ref instance, value); // reset field value
if (field.FieldType.IsInstanceOfType(newValue) is false)
{
throw new IncompatibleFieldTypeException($"expected field.GetValue(instance) is {field.FieldType.Name} " +
"(runtime sometimes allows setting fields to values of incompatible types without any above checks failing/throwing)");
}
}, expectedConstraint, testCaseLabel);
}