The format_exception(), format_exception_only(), and
print_exception() functions can now take an exception object as a positional-only argument.
Co-Authored-By: Matthias Bussonnier <bussonniermatthias@gmail.com>
This commit removes the old parser, the deprecated parser module, the old parser compatibility flags and environment variables and all associated support code and documentation.
This fixes both the traceback.py module and the C code for formatting syntax errors (in Python/pythonrun.c). They now both consistently do the following:
- Suppress caret if it points left of text
- Allow caret pointing just past end of line
- If caret points past end of line, clip to *just* past end of line
The syntax error formatting code in traceback.py was mostly rewritten; small, subtle changes were applied to the C code in pythonrun.c.
There's still a difference when the text contains embedded newlines. Neither handles these very well, and I don't think the case occurs in practice.
Automerge-Triggered-By: @gvanrossum
* Rename PyConfig.use_peg to _use_peg_parser
* Document PyConfig._use_peg_parser and mark it a deprecated
* Mark -X oldparser option and PYTHONOLDPARSER env var as deprecated
in the documentation.
* Add use_old_parser() and skip_if_new_parser() to test.support
* Remove sys.flags.use_peg: use_old_parser() uses
_testinternalcapi.get_configs() instead.
* Enhance test_embed tests
* subprocess._args_from_interpreter_flags() copies -X oldparser
Capturing exceptions into names can lead to reference cycles though the __traceback__ attribute of the exceptions in some obscure cases that have been reported previously and fixed individually. As these variables are not used anyway, we can remove the binding to reduce the chances of creating reference cycles.
See for example GH-13135
The recursive frame pruning code always undercounted the number of elided frames
by one. That is, in the "[Previous line repeated N more times]" message, N would
always be one too few. Near the recursive pruning cutoff, one frame could be
silently dropped. That situation is demonstrated in the OP of the bug report.
The fix is to start the identical frame counter at 1.
Running under coverage sometimes causes 'in comparison' to be added to the end of the RecursionError message, which is acceptable.
Patched by Maria Mckinley
This fixes a regression caused by revision 73afda5a4e4c. Also reverts the
decimal test workaround added in revision 5f3dd0a2b1ab.
Remove test_without_exception(). According to revision ecaafc32c500, this was
added in Python 2 so that print_exc() would output “None” when called with no
exception set. However print_exc() never worked like this in Python 3, and
the use case is not documented.
Restore TracebackCases class name (instead of SyntaxTracebackCases), because
the class also tests other exceptions.
* BUILD_TUPLE_UNPACK and BUILD_MAP_UNPACK_WITH_CALL no longer generated with
single tuple or dict.
* Restored more informative error messages for incorrect var-positional and
var-keyword arguments.
* Removed code duplications in _PyEval_EvalCodeWithName().
* Removed redundant runtime checks and parameters in _PyStack_AsDict().
* Added a workaround and enabled previously disabled test in test_traceback.
* Removed dead code from the dis module.
Issue #27213: Rework CALL_FUNCTION* opcodes to produce shorter and more
efficient bytecode:
* CALL_FUNCTION now only accepts position arguments
* CALL_FUNCTION_KW accepts position arguments and keyword arguments, but keys
of keyword arguments are packed into a constant tuple.
* CALL_FUNCTION_EX is the most generic, it expects a tuple and a dict for
positional and keyword arguments.
CALL_FUNCTION_VAR and CALL_FUNCTION_VAR_KW opcodes have been removed.
2 tests of test_traceback are currently broken: skip test, the issue #28050 was
created to track the issue.
Patch by Demur Rumed, design by Serhiy Storchaka, reviewed by Serhiy Storchaka
and Victor Stinner.
Large sections of repeated lines in tracebacks are now abbreviated as
"[Previous line repeated {count} more times]" by both the traceback
module and the builtin traceback rendering.
Patch by Emanuel Barry.
* 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.
Provide a way to seed the linecache for a PEP-302 module without actually
loading the code.
Provide a new object API for traceback, including the ability to not lookup
lines at all until the traceback is actually rendered, without any trace of the
original objects being kept alive.
Python finalization.
Before the module kept a reference to the builtins module, but the module
attributes are cleared during Python finalization. Instead, keep directly a
reference to the open() function.
This enhancement is not perfect, calling tokenize.open() can still fail if
called very late during Python finalization. Usually, the function is called
by the linecache module which is called to display a traceback or emit a
warning.
Irit Katriel
Zackery Spytz
Victor Stinner
Hai Shi
Pablo Galindo
Guido van Rossum
Serhiy Storchaka
Srinivas Thatiparthy (శ్రీనివాస్ తాటిపర్తి)
Berker Peksag
Benjamin Peterson
Zane Bitter
codedragon
Martin Panter
Eric V. Smith
Victor Stinner
Nick Coghlan
Robert Collins
Florent Xicluna