* Fix multiple typos in code comments
* Add spacing in comments (test_logging.py, test_math.py)
* Fix spaces at the beginning of comments in test_logging.py
f_trace_lines: enable/disable line trace events
f_trace_opcodes: enable/disable opcode trace events
These are intended primarily for testing of the interpreter
itself, as they make it much easier to emulate signals
arriving at unfortunate times.
* Constant statements will be ignored and the compiler will emit a
SyntaxWarning.
* Replace constant statement (ex: "1") with an expression statement
(ex: "x=1").
* test_traceback: use context manager on the file.
Issue #26204.
Many tests simply didn't care if they unset a pre-existing trace function. This
made test coverage impossible. This patch fixes various tests to put back any
pre-existing trace function. It also introduces test.support.no_tracing as a
decorator which will temporarily unset the trace function for tests which
simply fail otherwise.
Thanks to Kristian Vlaardingerbroek for helping to find the cause of various
trace function unsets.