The key question: Would changing thread scheduling, network latency, or a timeout alter correctness? Then you have connascence of timing.
Connascence of value
Connascence of value occurs when several values must be properly coordinated between modules. For instance, imagine you have a unit test that looks like this:
[Test]
procedure TestCheckoutValue {
PriceScanner = new TPriceScanner();
PriceScanner.Scan('Frosted Sugar Bombs');
Assert.Equals(50, PriceScanner.CurrentBalance);
}
So we’ve written the test. Now, in the spirit of Test Driven Development, I’ll make the test pass as easily and simply as possible.
void PriceScanner.Scan(aItem: string) {
CurrentBalance = 50;
}
We now have tight coupling between TPriceScanner and our test. We obviously have connascence of name, because both classes rely on the name CurrentBalance. But that’s relatively low-level connascence, and perfectly acceptable. We have connascence of type, because both must agree on the type TPriceScanner, but again, that’s benign. And we have connascence of meaning, because both routines have a hard-coded dependency on the number 50. That should be refactored.
