This uses [teyit](https://pypi.org/project/teyit/) to modernize asserts,
as recommended by the [unittest release
notes](https://docs.python.org/3.12/whatsnew/3.12.html#id3).

For example, `assertTrue(a == b)` is replaced with `assertEqual(a, b)`.
This produces better error messages, e.g. `error: unexpectedly found 1
and 2 to be different` instead of `error: False`.

assertEquals is a deprecated alias for assertEqual and has been removed
in Python 3.12. This wasn't an issue previously because we used a
vendored version of the unittest module. Now that we use the built-in
version this gets updated together with the Python version used to run
the test suite.

This is an ongoing series of commits that are reformatting our Python
code. Reformatting is done with `black` (23.1.0).

If you end up having problems merging this commit because you have made
changes to a python file, the best way to handle that is to run `git
checkout --ours <yourfile>` and then reformat it with black.

RFC: https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style

Differential revision: https://reviews.llvm.org/D151460

Not needed now that we require python 3.

Reviewed By: kastiglione, JDevlieghere

Differential Revision: https://reviews.llvm.org/D131761

Eliminate boilerplate of having each test manually assign to `mydir` by calling
`compute_mydir` in lldbtest.py.

Differential Revision: https://reviews.llvm.org/D128077

Replace forms of `assertTrue(err.Success())` with `assertSuccess(err)` (added in D82759).

* `assertSuccess` prints out the error's message
* `assertSuccess` expresses explicit higher level semantics, both to the reader and for test failure output
* `assertSuccess` seems not to be well known, using it where possible will help spread knowledge
* `assertSuccess` statements are more succinct

Differential Revision: https://reviews.llvm.org/D119616

I added some tests for the case where the breakpoints take immediately
to the extant test case, and made a new test case for when the source
regex breakpoint will be set in a dlopen-ed library.

I also noticed when doing this that "lldbutil.run_to_source_breakpoint
can't handle the case where the breakpoint will be in a dlopen-ed
library, since it requires the breakpoint to have at least 1 location
before run.  I fixed that by adding a parameter to say whether a
before run location is expected.

Differential Revision: https://reviews.llvm.org/D111920

This patch removes the infrastructure to replay the test suite from a
reproducer, as well as the modifications made to the individual tests.

At the moment nearly every test calls something similar to
`self.dbg.CreateTarget(self.getBuildArtifact("a.out"))` and them sometimes
checks if the created target is actually valid with something like
`self.assertTrue(target.IsValid(), "some useless text")`.

Beside being really verbose the error messages generated by this pattern are
always just indicating that the target failed to be created but now why.

This patch introduces a helper function `createTestTarget` to our Test class
that creates the target with the much more verbose `CreateTarget` overload that
gives us back an SBError (with a fancy error). If the target couldn't be created
the function prints out the SBError that LLDB returned and asserts for us. It
also defaults to the "a.out" build artifact path that nearly all tests are using
to avoid to hardcode "a.out" in every test.

I converted a bunch of tests to the new function but I'll do the rest of the
test suite as follow ups.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D102771

The side_effect Python package bypasses the reproducer instrumentation
and therefore these tests are not expected to replay from a reproducer.