cpython/Tools/peg_generator/pegen/build.py

248 lines
9.0 KiB
Python

import pathlib
import shutil
import tokenize
import sysconfig
import tempfile
import itertools
from typing import Optional, Tuple, List, IO, Set, Dict
from pegen.c_generator import CParserGenerator
from pegen.grammar import Grammar
from pegen.grammar_parser import GeneratedParser as GrammarParser
from pegen.parser import Parser
from pegen.parser_generator import ParserGenerator
from pegen.python_generator import PythonParserGenerator
from pegen.tokenizer import Tokenizer
MOD_DIR = pathlib.Path(__file__).resolve().parent
TokenDefinitions = Tuple[Dict[int, str], Dict[str, int], Set[str]]
def get_extra_flags(compiler_flags: str, compiler_py_flags_nodist: str) -> List[str]:
flags = sysconfig.get_config_var(compiler_flags)
py_flags_nodist = sysconfig.get_config_var(compiler_py_flags_nodist)
if flags is None or py_flags_nodist is None:
return []
return f"{flags} {py_flags_nodist}".split()
def compile_c_extension(
generated_source_path: str,
build_dir: Optional[str] = None,
verbose: bool = False,
keep_asserts: bool = True,
) -> str:
"""Compile the generated source for a parser generator into an extension module.
The extension module will be generated in the same directory as the provided path
for the generated source, with the same basename (in addition to extension module
metadata). For example, for the source mydir/parser.c the generated extension
in a darwin system with python 3.8 will be mydir/parser.cpython-38-darwin.so.
If *build_dir* is provided, that path will be used as the temporary build directory
of distutils (this is useful in case you want to use a temporary directory).
"""
import distutils.log
from distutils.core import Distribution, Extension
from distutils.command.clean import clean # type: ignore
from distutils.command.build_ext import build_ext # type: ignore
from distutils.tests.support import fixup_build_ext # type: ignore
if verbose:
distutils.log.set_verbosity(distutils.log.DEBUG)
source_file_path = pathlib.Path(generated_source_path)
extension_name = source_file_path.stem
extra_compile_args = get_extra_flags("CFLAGS", "PY_CFLAGS_NODIST")
extra_link_args = get_extra_flags("LDFLAGS", "PY_LDFLAGS_NODIST")
if keep_asserts:
extra_compile_args.append("-UNDEBUG")
extension = [
Extension(
extension_name,
sources=[
str(MOD_DIR.parent.parent.parent / "Python" / "Python-ast.c"),
str(MOD_DIR.parent.parent.parent / "Python" / "asdl.c"),
str(MOD_DIR.parent.parent.parent / "Parser" / "tokenizer.c"),
str(MOD_DIR.parent.parent.parent / "Parser" / "pegen.c"),
str(MOD_DIR.parent.parent.parent / "Parser" / "string_parser.c"),
str(MOD_DIR.parent / "peg_extension" / "peg_extension.c"),
generated_source_path,
],
include_dirs=[
str(MOD_DIR.parent.parent.parent / "Include" / "internal"),
str(MOD_DIR.parent.parent.parent / "Parser"),
],
extra_compile_args=extra_compile_args,
extra_link_args=extra_link_args,
)
]
dist = Distribution({"name": extension_name, "ext_modules": extension})
cmd = build_ext(dist)
fixup_build_ext(cmd)
cmd.inplace = True
if build_dir:
cmd.build_temp = build_dir
cmd.build_lib = build_dir
cmd.ensure_finalized()
cmd.run()
extension_path = source_file_path.parent / cmd.get_ext_filename(extension_name)
shutil.move(cmd.get_ext_fullpath(extension_name), extension_path)
cmd = clean(dist)
cmd.finalize_options()
cmd.run()
return extension_path
def build_parser(
grammar_file: str, verbose_tokenizer: bool = False, verbose_parser: bool = False
) -> Tuple[Grammar, Parser, Tokenizer]:
with open(grammar_file) as file:
tokenizer = Tokenizer(tokenize.generate_tokens(file.readline), verbose=verbose_tokenizer)
parser = GrammarParser(tokenizer, verbose=verbose_parser)
grammar = parser.start()
if not grammar:
raise parser.make_syntax_error(grammar_file)
return grammar, parser, tokenizer
def generate_token_definitions(tokens: IO[str]) -> TokenDefinitions:
all_tokens = {}
exact_tokens = {}
non_exact_tokens = set()
numbers = itertools.count(0)
for line in tokens:
line = line.strip()
if not line or line.startswith("#"):
continue
pieces = line.split()
index = next(numbers)
if len(pieces) == 1:
(token,) = pieces
non_exact_tokens.add(token)
all_tokens[index] = token
elif len(pieces) == 2:
token, op = pieces
exact_tokens[op.strip("'")] = index
all_tokens[index] = token
else:
raise ValueError(f"Unexpected line found in Tokens file: {line}")
return all_tokens, exact_tokens, non_exact_tokens
def build_c_generator(
grammar: Grammar,
grammar_file: str,
tokens_file: str,
output_file: str,
compile_extension: bool = False,
verbose_c_extension: bool = False,
keep_asserts_in_extension: bool = True,
skip_actions: bool = False,
) -> ParserGenerator:
with open(tokens_file, "r") as tok_file:
all_tokens, exact_tok, non_exact_tok = generate_token_definitions(tok_file)
with open(output_file, "w") as file:
gen: ParserGenerator = CParserGenerator(
grammar, all_tokens, exact_tok, non_exact_tok, file, skip_actions=skip_actions
)
gen.generate(grammar_file)
if compile_extension:
with tempfile.TemporaryDirectory() as build_dir:
compile_c_extension(
output_file,
build_dir=build_dir,
verbose=verbose_c_extension,
keep_asserts=keep_asserts_in_extension,
)
return gen
def build_python_generator(
grammar: Grammar, grammar_file: str, output_file: str, skip_actions: bool = False,
) -> ParserGenerator:
with open(output_file, "w") as file:
gen: ParserGenerator = PythonParserGenerator(grammar, file) # TODO: skip_actions
gen.generate(grammar_file)
return gen
def build_c_parser_and_generator(
grammar_file: str,
tokens_file: str,
output_file: str,
compile_extension: bool = False,
verbose_tokenizer: bool = False,
verbose_parser: bool = False,
verbose_c_extension: bool = False,
keep_asserts_in_extension: bool = True,
skip_actions: bool = False,
) -> Tuple[Grammar, Parser, Tokenizer, ParserGenerator]:
"""Generate rules, C parser, tokenizer, parser generator for a given grammar
Args:
grammar_file (string): Path for the grammar file
tokens_file (string): Path for the tokens file
output_file (string): Path for the output file
compile_extension (bool, optional): Whether to compile the C extension.
Defaults to False.
verbose_tokenizer (bool, optional): Whether to display additional output
when generating the tokenizer. Defaults to False.
verbose_parser (bool, optional): Whether to display additional output
when generating the parser. Defaults to False.
verbose_c_extension (bool, optional): Whether to display additional
output when compiling the C extension . Defaults to False.
keep_asserts_in_extension (bool, optional): Whether to keep the assert statements
when compiling the extension module. Defaults to True.
skip_actions (bool, optional): Whether to pretend no rule has any actions.
"""
grammar, parser, tokenizer = build_parser(grammar_file, verbose_tokenizer, verbose_parser)
gen = build_c_generator(
grammar,
grammar_file,
tokens_file,
output_file,
compile_extension,
verbose_c_extension,
keep_asserts_in_extension,
skip_actions=skip_actions,
)
return grammar, parser, tokenizer, gen
def build_python_parser_and_generator(
grammar_file: str,
output_file: str,
verbose_tokenizer: bool = False,
verbose_parser: bool = False,
skip_actions: bool = False,
) -> Tuple[Grammar, Parser, Tokenizer, ParserGenerator]:
"""Generate rules, python parser, tokenizer, parser generator for a given grammar
Args:
grammar_file (string): Path for the grammar file
output_file (string): Path for the output file
verbose_tokenizer (bool, optional): Whether to display additional output
when generating the tokenizer. Defaults to False.
verbose_parser (bool, optional): Whether to display additional output
when generating the parser. Defaults to False.
skip_actions (bool, optional): Whether to pretend no rule has any actions.
"""
grammar, parser, tokenizer = build_parser(grammar_file, verbose_tokenizer, verbose_parser)
gen = build_python_generator(grammar, grammar_file, output_file, skip_actions=skip_actions,)
return grammar, parser, tokenizer, gen