Hi dear Skylib maintainers,

right now we print the assertion error with the location .../external/bazel_skylib/lib/unittest.bzl:351:10:. It would be much more useful if we either printed the entire stack trace, or show the location of the callsite.

An argument could be made that there should be just one assertion per unit test, in that scenario this is not a problem. However there is so much boilerplate involved with adding a unit test that this is not practical to have one assertion per test. And even Bazel's internal BuildViewTestCase tests have multiple assertions per test.

Thank you!