Subtests are test sets linked to test results. It is easier to understand this by looking at a simple example.
1..3
ok 1 - First test
1..2
ok 1 - This is a subtest
ok 2 - So is this
1..2
ok 1 - This is a subtest
ok 2 - So is this
ok 2 - An example subtest
ok 3 - Third testIn the example above, we have a test set with three tests. But the first test has another test set, with two tests. This is an example of subtests.
This feature has been added in tap4j version 3.0.