Hi Ignite community!
I have a small proposition in regards to our testing.
We have an utility method called waitForCondition which we are using, as it
implies from the name of the method, to wait until some condition will be
met in the test. As soon as the condition is met this method returns true,
or false if the specified condition is not met for specified timeout.
After that our common pattern is to use assertTrue to verify whether
waitForCondition is completed successfully.
However we have a library awaitility in our test classpath in many modules
which are made for similar purposes. The main difference here is that this
library provides a clear message on what condition failed to meet in what
time frame.
Let's take a look at following example:
assertTrue(waitForCondition(() -> 60 == 61, 5_000));
In that case result of the assertion will be the following:
org.opentest4j.AssertionFailedError:
Expected :true
Actual :false
As we can see it is hard to understand what went wrong.
The same scenario using awaitility:
await().timeout(Duration.ofSeconds(5)).until(() -> 60, equalTo(61));
Will result in the following error:
org.awaitility.core.ConditionTimeoutException: Lambda expression in
org.apache.ignite.internal.ItApplyPartitionRaftLogOnAnotherNodesCompatibilityTest
expected <61> but was <60> within 5 seconds.
Not only is it easier to understand what we want to achieve in the
testing scenario, but the error message is much clearer compared to
waitForCondition.
Also, we have a very huge bug in waitForCondition where it will not
work at all if the supplier is frozen or executing more than specified
timeout. For example:
assertTrue(waitForCondition(() -> {
try {
Thread.sleep(10_000);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
return true;
}, 5_000));
I would've expected that this code snippet would fail after 5 seconds,
but it completes successfully after 10 seconds.
So my proposition to the community is to deprecate waitForCondition
completely and eventually switch to awaitility through the whole
Ignite code base.
Sincerely yours,
Ivan Zlenko.
