* bpo-15987: Implement ast.compare
Add a compare() function that compares two ASTs for structural equality. There are two set of attributes on AST node objects, fields and attributes. The fields are always compared, since they represent the actual structure of the code. The attributes can be optionally be included in the comparison. Attributes capture things like line numbers of column offsets, so comparing them involves test whether the layout of the program text is the same. Since whitespace seems inessential for comparing ASTs, the default is to compare fields but not attributes.
ASTs are just Python objects that can be modified in arbitrary ways. The API for ASTs is under-specified in the presence of user modifications to objects. The comparison respects modifications to fields and attributes, and to _fields and _attributes attributes. A user could create obviously malformed objects, and the code will probably fail with an AttributeError when that happens. (For example, adding "spam" to _fields but not adding a "spam" attribute to the object.)
Co-authored-by: Jeremy Hylton <jeremy@alum.mit.edu>
The PEP 649 implementation will require a way to load NotImplementedError
from the bytecode. @markshannon suggested implementing this by converting
LOAD_ASSERTION_ERROR into a more general mechanism for loading constants.
This PR adds this new opcode. I will work on the rest of the implementation
of the PEP separately.
Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
* expand on What's New entry for PEP 667 (including porting notes)
* define 'optimized scope' as a glossary term
* cover comprehensions and generator expressions in locals() docs
* review all mentions of "locals" in documentation (updating if needed)
* review all mentions of "f_locals" in documentation (updating if needed)
* Remove description of issue fixed in 3.5 from autospeccing guide
* Make autospeccing note text more succint and lint whitespace
* Add linting changes (missed in last commit)
---------
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
Many users think they want a locals argument for various reasons but they do not
understand that it makes code be treated as a class definition. They do not want
their code treated as a class definition and get surprised. The reason not
to pass locals specifically is that the following code raises a `NameError`:
```py
exec("""
def f():
print("hi")
f()
def g():
f()
g()
""", {}, {})
```
The reason not to leave out globals is as follows:
```py
def t():
exec("""
def f():
print("hi")
f()
def g():
f()
g()
""")
```
Nobody has been using a Sun machine for a long time. When I saw
this sentence in a lightning talk just now, I thought it was talking
about sending Python code on a spacecraft.
I honestly forgot this slipped into 3.13, but I think it's worth highlighting more, as it is a PEP-sized change that makes the type system significantly more powerful.
@Yhg1s I think it's also worth mentioning in your release announcements.
Suppress all `OSError` exceptions from `pathlib.Path.exists()` and `is_*()`
rather than a selection of more common errors as we do presently. Also
adjust the implementations to call `os.path.exists()` etc, which are much
faster on Windows thanks to GH-101196.
Follow-up of gh-101693. The previous DeprecationWarning is replaced with
raising sqlite3.ProgrammingError.
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Remove support for supplying additional positional arguments to
`PurePath.relative_to()` and `is_relative_to()`. This has been deprecated
since Python 3.12.
