Use f-strings for formatting strings

[umarcor]

Currently, we are using a deprecated syntax ("some text %s" % variable) for formatting strings. CI linting is complaining about it.

There are three alternatives:

• "some text %s".format(variable)"
• f"some text {variable}"
• "some text" + str(variable)

It seems that the official syntax going forward is the second one only (f-strings). I tried using the first one, but linters would still complain. With regard to the last one, that is not desirable I think, however, in some cases I found it necessary because I couldn't make it work using f-strings.

In this PR, most of the sources in the codebase are modified for using f-strings instead of "some text %s" % variable or "some text %s".format(variable)". The remaining sources belong to vunit/sim_if. I "fixed" those already, but I cannot test all of them. Hence, I decided to include the ghdl.py only, and handle those in an upcoming PR.

I followed the following guidelines:

• Replace %s with {VARIABLE!s}.
• Replace %r with {VARIABLE!r}.
• Replace %i with {VARIABLE:d}.
• Replace %.1f with {VARIABLE:.1f}.
• Replace "%s\n" % " ".join(cmd) with " ".join(cmd) + "\n", and "%s\n" % ("=" * (max(max_len + 25, 0))) with ("=" * (max(max_len + 25, 0))) + "\n".

[Paebbels]

What linter are you using?

[umarcor]

@Paebbels, see:

• https://github.com/VUnit/vunit/blob/master/pyproject.toml#L45
• https://github.com/VUnit/vunit/tree/master/tests/lint
  • https://github.com/VUnit/vunit/blob/master/tests/lint/test_pycodestyle.py
  • https://github.com/VUnit/vunit/blob/master/tests/lint/test_pylint.py

In this case, pycodestyle is passing, and pylint is failing. So:

vunit/tests/lint/test_pylint.py

Lines 26 to 33 in 14b5ad1

	check_call(
	[
	sys.executable,
	"-m",
	"pylint",
	"--rcfile=" + str(Path(__file__).parent / "pylintrc"),
	]
	+ get_files_and_folders()

and https://github.com/VUnit/vunit/blob/master/tests/lint/pylintrc.