check_set_special_type_attr() and type_set_annotations()
now check for immutable flag (Py_TPFLAGS_IMMUTABLETYPE).
Co-authored-by: Victor Stinner <vstinner@python.org>
The PyStdPrinter_Type type now uses the
Py_TPFLAGS_DISALLOW_INSTANTIATION flag to disallow instantiation,
rather than seting a tp_init method which always fail.
Write also unit tests for PyStdPrinter_Type.
Add a new Py_TPFLAGS_DISALLOW_INSTANTIATION type flag to disallow
creating type instances: set tp_new to NULL and don't create the
"__new__" key in the type dictionary.
The flag is set automatically on static types if tp_base is NULL or
&PyBaseObject_Type and tp_new is NULL.
Use the flag on the following types:
* _curses.ncurses_version type
* _curses_panel.panel
* _tkinter.Tcl_Obj
* _tkinter.tkapp
* _tkinter.tktimertoken
* _xxsubinterpretersmodule.ChannelID
* sys.flags type
* sys.getwindowsversion() type
* sys.version_info type
Update MyStr example in the C API documentation to use
Py_TPFLAGS_DISALLOW_INSTANTIATION.
Add _PyStructSequence_InitType() function to create a structseq type
with the Py_TPFLAGS_DISALLOW_INSTANTIATION flag set.
type_new() calls _PyType_CheckConsistency() at exit.
Add inspect.get_annotations, which safely computes the annotations defined on an object. It works around the quirks of accessing the annotations from various types of objects, and makes very few assumptions about the object passed in. inspect.get_annotations can also correctly un-stringize stringized annotations.
inspect.signature, inspect.from_callable, and inspect.from_function now call inspect.get_annotations to retrieve annotations. This means inspect.signature and inspect.from_callable can now un-stringize stringized annotations, too.
While working on another issue, I noticed two minor nits in the C implementation of the module object. Both are related to getting a module's name.
First, the C function module_dir() (module.__dir__) starts by ensuring the module dict is valid. If the module dict is invalid, it wants to format an exception using the name of the module, which it gets from PyModule_GetName(). However, PyModule_GetName() gets the name of the module from the dict. So getting the name in this circumstance will never succeed.
When module_dir() wants to format the error but can't get the name, it knows that PyModule_GetName() must have already raised an exception. So it leaves that exception alone and returns an error. The end result is that the exception raised here is kind of useless and misleading: dir(module) on a module with no __dict__ raises SystemError("nameless module"). I changed the code to actually raise the exception it wanted to raise, just without a real module name: TypeError("<module>.__dict__ is not a dictionary"). This seems more useful, and would do a better job putting the programmer who encountered this on the right track of figuring out what was going on.
Second, the C API function PyModule_GetNameObject() checks to see if the module has a dict. If m->md_dict is not NULL, it calls _PyDict_GetItemIdWithError(). However, it's possible for m->md_dict to be None. And if you call _PyDict_GetItemIdWithError(Py_None, ...) it will *crash*.
Unfortunately, this crash was due to my own bug in the other branch. Fixing my code made the crash go away. I assert that this is still possible at the API level.
The fix is easy: add a PyDict_Check() to PyModule_GetNameObject().
Unfortunately, I don't know how to add a unit test for this. Having changed module_dir() above, I can't find any other interfaces callable from Python that eventually call PyModule_GetNameObject(). So I don't know how to trick the runtime into reproducing this error.
Since both these changes are minor--each entails only a small edit to only one line--I didn't bother with a news item.
Change class and module objects to lazy-create empty annotations dicts on demand. The annotations dicts are stored in the object's `__dict__` for backwards compatibility.
* Add length parameter to PyLineTable_InitAddressRange and doen't use sentinel values at end of table. Makes the line number table more robust.
* Update PyCodeAddressRange to match PEP 626.
Removes the `list` call in the Popen `repr`.
Current implementation:
For cmd = `python --version`, with `shell=True`.
```bash
<Popen: returncode: None args: ['p', 'y', 't', 'h', 'o', 'n', ' ', '-', '-',...>
```
For `shell=False` and args=`['python', '--version']`, the output is correct:
```bash
<Popen: returncode: None args: ['python', '--version']>
```
With the new changes the `repr` yields:
For cmd = `python --version`, with `shell=True`:
```bash
<Popen: returncode: None args: 'python --version'>
```
For `shell=False` and args=`['python', '--version']`, the output:
```bash
<Popen: returncode: None args: ['python', '--version']>
```
Automerge-Triggered-By: GH:gpshead
In 3.12 ``True`` or ``False`` will be returned for all containment checks,
with ``True`` being returned if the value is either a member of that enum
or one of its members' value.
In 3.12 the enum member, not the member's value, will be used for
format() calls. Format specifiers can be used to retain the current
display of enum members:
Example enumeration:
class Color(IntEnum):
RED = 1
GREEN = 2
BLUE = 3
Current behavior:
f'{Color.RED}' --> '1'
Future behavior:
f'{Color.RED}' --> 'RED'
Using d specifier:
f'{Color.RED:d}' --> '1'
Using specifiers can be done now and is future-compatible.