We're no longer using _Py_IDENTIFIER() (or _Py_static_string()) in any core CPython code. It is still used in a number of non-builtin stdlib modules.
The replacement is: PyUnicodeObject (not pointer) fields under _PyRuntimeState, statically initialized as part of _PyRuntime. A new _Py_GET_GLOBAL_IDENTIFIER() macro facilitates lookup of the fields (along with _Py_GET_GLOBAL_STRING() for non-identifier strings).
https://bugs.python.org/issue46541#msg411799 explains the rationale for this change.
The core of the change is in:
* (new) Include/internal/pycore_global_strings.h - the declarations for the global strings, along with the macros
* Include/internal/pycore_runtime_init.h - added the static initializers for the global strings
* Include/internal/pycore_global_objects.h - where the struct in pycore_global_strings.h is hooked into _PyRuntimeState
* Tools/scripts/generate_global_objects.py - added generation of the global string declarations and static initializers
I've also added a --check flag to generate_global_objects.py (along with make check-global-objects) to check for unused global strings. That check is added to the PR CI config.
The remainder of this change updates the core code to use _Py_GET_GLOBAL_IDENTIFIER() instead of _Py_IDENTIFIER() and the related _Py*Id functions (likewise for _Py_GET_GLOBAL_STRING() instead of _Py_static_string()). This includes adding a few functions where there wasn't already an alternative to _Py*Id(), replacing the _Py_Identifier * parameter with PyObject *.
The following are not changed (yet):
* stop using _Py_IDENTIFIER() in the stdlib modules
* (maybe) get rid of _Py_IDENTIFIER(), etc. entirely -- this may not be doable as at least one package on PyPI using this (private) API
* (maybe) intern the strings during runtime init
https://bugs.python.org/issue46541
@pablogsal, sorry i failed to rebase to main, so i recreated https://github.com/python/cpython/pull/22190#issuecomment-1024633392
> PyRun_InteractiveOne\*() functions allow to explicitily set fd instead of stdin.
but stdin was hardcoded in readline call.
> This patch does not fix target file for prompt unlike original bpo one : prompt fd is unrelated to tokenizer source which could be read only. It is more of a bugfix regarding the docs : actual documentation say "prompt the user" so one would expect prompt to go on stdout not a file for both PyRun_InteractiveOne\*() and PyRun_InteractiveLoop\*().
Automerge-Triggered-By: GH:pablogsal
* Move _PyObject_CallNoArgs() to pycore_call.h (internal C API).
* _ssl, _sqlite and _testcapi extensions now call the public
PyObject_CallNoArgs() function, rather than _PyObject_CallNoArgs().
* _lsprof extension is now built with Py_BUILD_CORE_MODULE macro
defined to get access to internal _PyObject_CallNoArgs().
Fix typo in the private _PyObject_CallNoArg() function name: rename
it to _PyObject_CallNoArgs() to be consistent with the public
function PyObject_CallNoArgs().
Emit a deprecation warning if the numeric literal is immediately followed by
one of keywords: and, else, for, if, in, is, or. Raise a syntax error with
more informative message if it is immediately followed by other keyword or
identifier.
Automerge-Triggered-By: GH:pablogsal
When the parser does a second pass to check for errors, these rules can
have some small side-effects as they may advance the parser more than
the point reached in the first pass. This can cause the tokenizer to ask
for extra tokens in interactive mode causing the tokenizer to show the
prompt instead of failing instantly.
To avoid this, add a new mode to the tokenizer that is activated in the
second pass and deactivates asking for new tokens when the interactive
line is finished. As the parsing should have reached the last line in
the first pass, the second pass should not need to ask for more tokens.
When trying to extract the error line for the error message there
are two distinct cases:
1. The input comes from a file, which means that we can extract the
error line by using `PyErr_ProgramTextObject` and which we already
do.
2. The input does not come from a file, at which point we need to get
the source code from the tokenizer:
* If the tokenizer's current line number is the same with the line
of the error, we get the line from `tok->buf` and we're ready.
* Else, we can extract the error line from the source code in the
following two ways:
* If the input comes from a string we have all the input
in `tok->str` and we can extract the error line from it.
* If the input comes from stdin, i.e. the interactive prompt, we
do not have access to the previous line. That's why a new
field `tok->stdin_content` is added which holds the whole input for the
current (multiline) statement or expression. We can then extract the
error line from `tok->stdin_content` like we do in the string case above.
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
No longer use deprecated aliases to functions:
* Replace PyMem_MALLOC() with PyMem_Malloc()
* Replace PyMem_REALLOC() with PyMem_Realloc()
* Replace PyMem_FREE() with PyMem_Free()
* Replace PyMem_Del() with PyMem_Free()
* Replace PyMem_DEL() with PyMem_Free()
Modify also the PyMem_DEL() macro to use directly PyMem_Free().
On Windows, #include "pyerrors.h" no longer defines "snprintf" and
"vsnprintf" macros.
PyOS_snprintf() and PyOS_vsnprintf() should be used to get portable
behavior.
Replace snprintf() calls with PyOS_snprintf() and replace vsnprintf()
calls with PyOS_vsnprintf().
A line with only a line continuation character should be considered
a blank line at tokenizer level so that only a single NEWLINE token
gets emitted. The old parser was working around the issue, but the
new parser threw a `SyntaxError` for valid input. For example,
an empty line following a line continuation character was interpreted
as a `SyntaxError`.
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
Due to backwards compatibility concerns regarding keywords immediately followed by a string without whitespace between them (like in `bg="#d00" if clear else"#fca"`) will fail to parse,
commit 41d5b94af4 has to be reverted.
The Py_FatalError() function is replaced with a macro which logs
automatically the name of the current function, unless the
Py_LIMITED_API macro is defined.
Changes:
* Add _Py_FatalErrorFunc() function.
* Remove the function name from the message of Py_FatalError() calls
which included the function name.
* Update tests.
The function PyTokenizer_FromUTF8 from Parser/tokenizer.c had a comment:
/* XXX: constify members. */
This patch addresses that.
In the tok_state struct:
* end and start were non-const but could be made const
* str and input were const but should have been non-const
Changes to support this include:
* decode_str() now returns a char * since it is allocated.
* PyTokenizer_FromString() and PyTokenizer_FromUTF8() each creates a
new char * for an allocate string instead of reusing the input
const char *.
* PyTokenizer_Get() and tok_get() now take const char ** arguments.
* Various local vars are const or non-const accordingly.
I was able to remove five casts that cast away constness.
This disallows things like `# type: ignoreé`, which seems wrong.
Also switch to using Py_ISALNUM for the alnum check, for consistency
with other code (and maybe correctness re: locale issues?).
https://bugs.python.org/issue36878
GH-13238 made extra text after a # type: ignore accepted by the parser.
This finishes the job and actually plumbs the extra text through the
parser and makes it available in the AST.
This makes the parser consistent with the tokenize module (already the case
in `pypy`).
sample
------
```python
x = 5\
```
before
------
```console
$ python3 t.py
$ python3 -mtokenize t.py
t.py:2:0: error: EOF in multi-line statement
```
after
-----
```console
$ ./python t.py
File "t.py", line 3
x = 5\
^
SyntaxError: unexpected EOF while parsing
$ ./python -m tokenize t.py
t.py:2:0: error: EOF in multi-line statement
```
https://bugs.python.org/issue2180
In the parser, when using the type_comments=True option, recognize
a TYPE_IGNORE as anything containing `# type: ignore` followed by
a non-alphanumeric character. This is to allow ignores such as
`# type: ignore[E1000]`.
This adds a `feature_version` flag to `ast.parse()` (documented) and `compile()` (hidden) that allow tweaking the parser to support older versions of the grammar. In particular if `feature_version` is 5 or 6, the hacks for the `async` and `await` keyword from PEP 492 are reinstated. (For 7 or higher, these are unconditionally treated as keywords, but they are still special tokens rather than `NAME` tokens that the parser driver recognizes.)
https://bugs.python.org/issue35975
Pgen is the oldest piece of technology in the CPython repository, building it requires various #if[n]def PGEN hacks in other parts of the code and it also depends more and more on CPython internals. This commit removes the old pgen C code and replaces it for a new version implemented in pure Python. This is a modified and adapted version of lib2to3/pgen2 that can generate grammar files compatibles with the current parser.
This commit also eliminates all the #ifdef and code branches related to pgen, simplifying the code and making it more maintainable. The regen-grammar step now uses $(PYTHON_FOR_REGEN) that can be any version of the interpreter, so the new pgen code maintains compatibility with older versions of the interpreter (this also allows regenerating the grammar with the current CI solution that uses Python3.5). The new pgen Python module also makes use of the Grammar/Tokens file that holds the token specification, so is always kept in sync and avoids having to maintain duplicate token definitions.
"Include/token.h", "Lib/token.py" (containing now some data moved from
"Lib/tokenize.py") and new files "Parser/token.c" (containing the code
moved from "Parser/tokenizer.c") and "Doc/library/token-list.inc" (included
in "Doc/library/token.rst") are now generated from "Grammar/Tokens" by
"Tools/scripts/generate_token.py". The script overwrites files only if
needed and can be used on the read-only sources tree.
"Lib/symbol.py" is now generated by "Tools/scripts/generate_symbol_py.py"
instead of been executable itself.
Added new make targets "regen-token" and "regen-symbol" which are now
dependencies of "regen-all".
The documentation contains now strings for operators and punctuation tokens.
Remove the following fields from tok_state structure which are now
used unused:
* altwarning: "Issue warning if alternate tabs don't match"
* alterror: "Issue error if alternate tabs don't match"
* alttabsize: "Alternate tab spacing"
Replace alttabsize variable with ALTTABSIZE define.
* add test to check if were modifying token
* copy list so import tokenize doesnt have side effects on token
* shorten line
* add tokenize tokens to token.h to get them to show up in token
* move ERRORTOKEN back to its previous location, and fix nitpick
* copy comments from token.h automatically
* fix whitespace and make more pythonic
* change to fix comments from @haypo
* update token.rst and Misc/NEWS
* change wording
* some more wording changes
This commit simplifies async/await tokenization in tokenizer.c,
tokenize.py & lib2to3/tokenize.py. Previous solution was to keep
a stack of async-def & def blocks, whereas the new approach is just
to remember position of the outermost async-def block.
This change won't bring any parsing performance improvements, but
it makes the code much easier to read and validate.
This commit fixes how one-line async-defs and defs are tracked
by tokenizer. It allows to correctly parse invalid code such
as:
>>> async def f():
... def g(): pass
... async = 10
and valid code such as:
>>> async def f():
... async def g(): pass
... await z
As a consequence, is is now possible to have one-line
'async def foo(): await ..' functions:
>>> async def foo(): return await bar()
Eric Snow
