Change FOR_ITER to have the same stack effect regardless of whether it branches or not.
Performance is unchanged as FOR_ITER (and specialized forms jump over the cleanup code).
In `_warnings.c`, in the C equivalent of `warnings.warn_explicit()`, if the module globals are given (and not None), the warning will attempt to get the source line for the issued warning. To do this, it needs the module's loader.
Previously, it would only look up `__loader__` in the module globals. In https://github.com/python/cpython/issues/86298 we want to defer to the `__spec__.loader` if available.
The first step on this journey is to check that `loader == __spec__.loader` and issue another warning if it is not. This commit does that.
Since this is a PoC, only manual testing for now.
```python
# /tmp/foo.py
import warnings
import bar
warnings.warn_explicit(
'warning!',
RuntimeWarning,
'bar.py', 2,
module='bar knee',
module_globals=bar.__dict__,
)
```
```python
# /tmp/bar.py
import sys
import os
import pathlib
# __loader__ = pathlib.Path()
```
Then running this: `./python.exe -Wdefault /tmp/foo.py`
Produces:
```
bar.py:2: RuntimeWarning: warning!
import os
```
Uncomment the `__loader__ = ` line in `bar.py` and try it again:
```
sys:1: ImportWarning: Module bar; __loader__ != __spec__.loader (<_frozen_importlib_external.SourceFileLoader object at 0x109f7dfa0> != PosixPath('.'))
bar.py:2: RuntimeWarning: warning!
import os
```
Automerge-Triggered-By: GH:warsaw
This is a small performance improvement, especially for one or two hot
places such as _handle_fromlist() that are called a lot and the
.format() method was being used just to join two strings with a dot.
Otherwise it is merely a readability improvement.
We keep `_ERR_MSG` and `_ERR_MSG_PREFIX` as those may be used elsewhere for canonical looking error messages.
Support for bytes broke sometime between Python 3.2 and 3.6 and has been broken ever since. Trying to bring back supports is surprisingly difficult in the face of -b and checking for keys in sys.path_importer_cache. Since the support was broken for so long, trying to overcome the difficulty of bringing back the support has been deemed not worth it.
Co-authored-by: Eryk Sun <eryksun@gmail.com>
Co-authored-by: Brett Cannon <brett@python.org>
Fix the importlib.resources.as_file() context manager to remove the
temporary file if destroyed late during Python finalization: keep a
local reference to the os.remove() function. Patch by Victor Stinner.
* Stores all location info in linetable to conform to PEP 626.
* Remove column table from code objects.
* Remove end-line table from code objects.
* Document new location table format
Confirmed with @jaraco that this indeed needs a fix.
A question that came up while I was digging into the code: I think `SelectableGroups` could similarly use `__slots__ = ()`, since its purpose seems only for convenience around `dict`, not to have attributes of its own.
Automerge-Triggered-By: GH:jaraco
* Add PRECALL_FUNCTION opcode.
* Move 'call shape' varaibles into struct.
* Replace CALL_NO_KW and CALL_KW with KW_NAMES and CALL instructions.
* Specialize for builtin methods taking using the METH_FASTCALL | METH_KEYWORDS protocol.
* Allow kwnames for specialized calls to builtin types.
* Specialize calls to tuple(arg) and str(arg).
* Add RETURN_GENERATOR and JUMP_NO_INTERRUPT opcodes.
* Trim frame and generator by word each.
* Minor refactor of frame.c
* Update test.test_sys to account for smaller frames.
* Treat generator functions as normal functions when evaluating and specializing.
* Do not PUSH/POP traceback or type to the stack as part of exc_info
* Remove exc_traceback and exc_type from _PyErr_StackItem
* Add to what's new, because this change breaks things like Cython
* bpo-44893: Implement EntryPoint as simple class and deprecate tuple access in favor of attribute access. Syncs with importlib_metadata 4.8.1.
* Apply refactorings found in importlib_metadata 4.8.2.
* bpo-45514: Apply changes from importlib_resources@a3ef4128c6
* Mark legacy functions as deprecated in the docs and link to the migration docs in importlib_resources docs.
* Apply changes from importlib_resources@329ae9d5f2c.
* Indicate importlib.resources as a module.
Co-authored-by: Filipe Laíns <lains@riseup.net>
* Make internal APIs that take PyFrameConstructor take a PyFunctionObject instead.
* Add reference to function to frame, borrow references to builtins and globals.
* Add COPY_FREE_VARS instruction to allow specialization of calls to inner functions.
Rename namespace package __loader__ class to be public.
Make the old name, i.e. _NamespaceLoader, an alias for the public name, for backward compatibility.
Currently frozen modules do not have __file__ set. In their spec, origin is set to "frozen" and they are marked as not having a location. (Similarly, for frozen packages __path__ is set to an empty list.) However, for frozen stdlib modules we are able to extrapolate __file__ as long as we can determine the stdlib directory at runtime. (We now do so since gh-28586.) Having __file__ set is helpful for a number of reasons. Likewise, having a non-empty __path__ means we can import submodules of a frozen package from the filesystem (e.g. we could partially freeze the encodings module).
This change sets __file__ (and adds to __path__) for frozen stdlib modules. It uses sys._stdlibdir (from gh-28586) and the frozen module alias information (from gh-28655). All that work is done in FrozenImporter (in Lib/importlib/_bootstrap.py).
Also, if a frozen module is imported before importlib is bootstrapped (during interpreter initialization) then we fix up that module and its spec during the importlib bootstrapping step (i.e. imporlib._bootstrap._setup()) to match what gets set by FrozenImporter, including setting the file info (if the stdlib dir is known). To facilitate this, modules imported using PyImport_ImportFrozenModule() have __origname__ set using the frozen module alias info. __origname__ is popped off during importlib bootstrap.
(To be clear, even with this change the new code to set __file__ during fixups in imporlib._bootstrap._setup() doesn't actually get triggered yet. This is because sys._stdlibdir hasn't been set yet in interpreter initialization at the point importlib is bootstrapped. However, we do fix up such modules at that point to otherwise match the result of importing through FrozenImporter, just not the __file__ and __path__ parts. Doing so will require changes in the order in which things happen during interpreter initialization. That can be addressed separately. Once it is, the file-related fixup code from this PR will kick in.)
Here are things this change does not do:
* set __file__ for non-stdlib modules (no way of knowing the parent dir)
* set __file__ if the stdlib dir is not known (nor assume the expense of finding it)
* relatedly, set __file__ if the stdlib is in a zip file
* verify that the filename set to __file__ actually exists (too expensive)
* update __path__ for frozen packages that alias a non-package (since there is no package dir)
Other things this change skips, but we may do later:
* set __file__ on modules imported using PyImport_ImportFrozenModule()
* set co_filename when we unmarshal the frozen code object while importing the module (e.g. in FrozenImporter.exec_module()) -- this would allow tracebacks to show source lines
* implement FrozenImporter.get_filename() and FrozenImporter.get_source()
https://bugs.python.org/issue21736
In the list of generated frozen modules at the top of Tools/scripts/freeze_modules.py, you will find that some of the modules have a different name than the module (or .py file) that is actually frozen. Let's call each case an "alias". Aliases do not come into play until we get to the (generated) list of modules in Python/frozen.c. (The tool for freezing modules, Programs/_freeze_module, is only concerned with the source file, not the module it will be used for.)
Knowledge of which frozen modules are aliases (and the identity of the original module) normally isn't important. However, this information is valuable when we go to set __file__ on frozen stdlib modules. This change updates Tools/scripts/freeze_modules.py to map aliases to the original module name (or None if not a stdlib module) in Python/frozen.c. We also add a helper function in Python/import.c to look up a frozen module's alias and add the result of that function to the frozen info returned from find_frozen().
https://bugs.python.org/issue45020
Before this change we end up duplicating effort and throwing away data in FrozenImporter.find_spec(). Now we do the work once in find_spec() and the only thing we do in FrozenImporter.exec_module() is turn the raw frozen data into a code object and then exec it.
We've added _imp.find_frozen(), add an arg to _imp.get_frozen_object(), and updated FrozenImporter. We've also moved some code around to reduce duplication, get a little more consistency in outcomes, and be more efficient.
Note that this change is mostly necessary if we want to set __file__ on frozen stdlib modules. (See https://bugs.python.org/issue21736.)
https://bugs.python.org/issue45324
Implements a two steps check in `importlib._bootstrap._find_and_load()` to avoid locking when the module has been already imported and it's ready.
---
Using `importlib.__import__()`, after this, does show a big difference:
Before:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
15.92248619502061
```
After:
```
$ ./python -c 'import timeit; print(timeit.timeit("__import__(\"timeit\")", setup="from importlib import __import__"))'
1.206068897008663
```
---
This PR is part of PEP 657 and augments the compiler to emit ending
line numbers as well as starting and ending columns from the AST
into compiled code objects. This allows bytecodes to be correlated
to the exact source code ranges that generated them.
This information is made available through the following public APIs:
* The `co_positions` method on code objects.
* The C API function `PyCode_Addr2Location`.
Co-authored-by: Batuhan Taskaya <isidentical@gmail.com>
Co-authored-by: Ammar Askar <ammar@ammaraskar.com>
Currently, if an arg value escapes (into the closure for an inner function) we end up allocating two indices in the fast locals even though only one gets used. Additionally, using the lower index would be better in some cases, such as with no-arg `super()`. To address this, we update the compiler to fix the offsets so each variable only gets one "fast local". As a consequence, now some cell offsets are interspersed with the locals (only when an arg escapes to an inner function).
https://bugs.python.org/issue43693
This was reverted in GH-26596 (commit 6d518bb) due to some bad memory accesses.
* Add the MAKE_CELL opcode. (gh-26396)
The memory accesses have been fixed.
https://bugs.python.org/issue43693
Mark Shannon
Jason R. Coombs
Barry Warsaw
Gregory P. Smith
Nikita Sobolev
Brett Cannon
Irit Katriel
Brandt Bucher
Thomas Grainger
Dennis Sweeney
Ken Jin
Victor Stinner
Christian Heimes
Serhiy Storchaka
Arie Bovenberg
Brandt Bucher
penguin_wwy
Miro Hrončok
Eric Snow
Christian Clauss
Hugo van Kemenade
Germán Méndez Bravo
Filipe Laíns
Pablo Galindo Salgado
Gabriele N. Tornetta
Batuhan Taskaya
Guido van Rossum
Sebastian Rittau
Binbin