feat(parser): generate python AST classes

use the generation script to create Python AST node classes, also distinguish between Midas type annotation nodes and statements
This commit is contained in:
2026-05-25 20:53:36 +02:00
parent 939e5af4ce
commit 0bbdf04621
5 changed files with 122 additions and 56 deletions

View File

@@ -48,7 +48,7 @@ class {cls}({base}):
"""
SECTION_REGEX = re.compile(
r"^###>\s*(?P<base>[^\n]*?)\s*\|\s*(?P<name>[^\n]*?)\s*?\n(?P<body>.*?)\n###<$",
r"^###>\s*(?P<base>[^\n]*?)\s*\|\s*(?P<name>[^\n]*?)(\s*\|\s*(?P<param>[^\n]*?))?\s*?\n(?P<body>.*?)\n###<$",
re.MULTILINE | re.DOTALL,
)
@@ -87,15 +87,15 @@ def make_banner(text: str) -> str:
return "\n".join((rule, middle, rule))
def make_section(full_name: str, base: str, body: str) -> str:
def make_section(full_name: str, base: str, param: str, body: str) -> str:
visitor_methods: list[str] = []
classes: list[str] = []
definitions: list[str] = body.strip("\n").split("\n\n")
definitions: list[str] = body.strip("\n").split("\n\n\n")
for cls in definitions:
cls = cls.strip("\n")
name: str = re.match("class (.*?):", cls).group(1) # type: ignore
print(f"Processing {name}")
visitor_methods.append(make_visitor_method(name, base.lower()))
visitor_methods.append(make_visitor_method(name, param))
classes.append(make_class(name, cls, base))
return SECTION_TEMPLATE.format(
@@ -119,8 +119,9 @@ def generate(definitions_path: Path, out_path: Path):
for section_m in SECTION_REGEX.finditer(src):
full_name: str = section_m.group("name")
base: str = section_m.group("base")
param: str = section_m.group("param") or base.lower()
body: str = section_m.group("body")
sections.append(make_section(full_name, base, body))
sections.append(make_section(full_name, base, param, body))
result: str = TEMPLATE.format(
header=HEADER.format(
@@ -138,6 +139,7 @@ def main():
defs_dir: Path = root / "gen"
ast_dir: Path = root / "midas" / "ast"
generate(defs_dir / "midas.py", ast_dir / "midas.py")
generate(defs_dir / "python.py", ast_dir / "python.py")
if __name__ == "__main__":

53
gen/python.py Normal file
View File

@@ -0,0 +1,53 @@
# type: ignore
# ruff: disable[F821, F401]
###> Imports
import ast
from abc import ABC, abstractmethod
from dataclasses import dataclass
from typing import Generic, Optional, TypeVar
from midas.ast.location import Location
###<
###> MidasType | Type annotations | node
class BaseType:
base: str
param: Optional[MidasType]
class ConstraintType:
type: MidasType
constraint: ast.expr
class FrameColumn:
name: Optional[str]
type: Optional[MidasType]
class FrameType:
columns: list[FrameColumn]
###<
###> Stmt | Statements
class Function:
name: str
posonlyargs: list[Argument]
args: list[Argument]
kwonlyargs: list[Argument]
returns: Optional[MidasType]
@dataclass(frozen=True, kw_only=True)
class Argument:
location: Optional[Location] = None
name: Optional[str]
type: Optional[MidasType]
###<

View File

@@ -350,7 +350,7 @@ class MidasPrinter(m.Expr.Visitor[str], m.Stmt.Visitor[str]):
return f"{expr.name.lexeme}{template}{'?' if expr.optional else ''}"
class PythonAstPrinter(AstPrinter, p.Expr.Visitor[None]):
class PythonAstPrinter(AstPrinter, p.MidasType.Visitor[None], p.Stmt.Visitor[None]):
def visit_base_type(self, node: p.BaseType) -> None:
self._write_line("BaseType")
with self._child_level():
@@ -382,39 +382,39 @@ class PythonAstPrinter(AstPrinter, p.Expr.Visitor[None]):
self._mark_last()
col.accept(self)
def visit_function(self, node: p.Function) -> None:
def visit_function(self, stmt: p.Function) -> None:
self._write_line("Function")
with self._child_level():
self._write_line(f"name: {node.name}")
self._write_line(f"name: {stmt.name}")
self._write_line("posonlyargs")
with self._child_level():
for i, arg in enumerate(node.posonlyargs):
for i, arg in enumerate(stmt.posonlyargs):
self._idx = i
if i == len(node.posonlyargs) - 1:
if i == len(stmt.posonlyargs) - 1:
self._mark_last()
arg.accept(self)
self._print_argument(arg)
self._write_line("args")
with self._child_level():
for i, arg in enumerate(node.args):
for i, arg in enumerate(stmt.args):
self._idx = i
if i == len(node.args) - 1:
if i == len(stmt.args) - 1:
self._mark_last()
arg.accept(self)
self._print_argument(arg)
self._write_line("kwonlyargs")
with self._child_level():
for i, arg in enumerate(node.kwonlyargs):
for i, arg in enumerate(stmt.kwonlyargs):
self._idx = i
if i == len(node.kwonlyargs) - 1:
if i == len(stmt.kwonlyargs) - 1:
self._mark_last()
arg.accept(self)
self._print_argument(arg)
self._write_optional_child("returns", node.returns, last=True)
self._write_optional_child("returns", stmt.returns, last=True)
def visit_function_argument(self, node: p.FunctionArgument) -> None:
def _print_argument(self, arg: p.Function.Argument) -> None:
self._write_line("FunctionArgument")
with self._child_level():
self._write_line(f"name: {node.name}")
self._write_optional_child("type", node.type, last=True)
self._write_line(f"name: {arg.name}")
self._write_optional_child("type", arg.type, last=True)

View File

@@ -1,7 +1,12 @@
"""
This file was generated by a script. Any manual changes might be overwritten.
Please modify gen/python.py instead and run gen/gen.py
"""
from __future__ import annotations
from abc import ABC, abstractmethod
import ast
from abc import ABC, abstractmethod
from dataclasses import dataclass
from typing import Generic, Optional, TypeVar
@@ -9,9 +14,13 @@ from midas.ast.location import Location
T = TypeVar("T")
####################
# Type annotations #
####################
@dataclass(frozen=True, kw_only=True)
class Expr(ABC):
class MidasType(ABC):
location: Optional[Location] = None
@abstractmethod
@@ -30,24 +39,13 @@ class Expr(ABC):
@abstractmethod
def visit_frame_type(self, node: FrameType) -> T: ...
@abstractmethod
def visit_function(self, node: Function) -> T: ...
@abstractmethod
def visit_function_argument(self, node: FunctionArgument) -> T: ...
@dataclass(frozen=True)
class MidasType(Expr):
pass
@dataclass(frozen=True)
class BaseType(MidasType):
base: str
param: Optional[MidasType]
def accept(self, visitor: Expr.Visitor[T]) -> T:
def accept(self, visitor: MidasType.Visitor[T]) -> T:
return visitor.visit_base_type(self)
@@ -56,7 +54,7 @@ class ConstraintType(MidasType):
type: MidasType
constraint: ast.expr
def accept(self, visitor: Expr.Visitor[T]) -> T:
def accept(self, visitor: MidasType.Visitor[T]) -> T:
return visitor.visit_constraint_type(self)
@@ -65,7 +63,7 @@ class FrameColumn(MidasType):
name: Optional[str]
type: Optional[MidasType]
def accept(self, visitor: Expr.Visitor[T]) -> T:
def accept(self, visitor: MidasType.Visitor[T]) -> T:
return visitor.visit_frame_column(self)
@@ -73,26 +71,40 @@ class FrameColumn(MidasType):
class FrameType(MidasType):
columns: list[FrameColumn]
def accept(self, visitor: Expr.Visitor[T]) -> T:
def accept(self, visitor: MidasType.Visitor[T]) -> T:
return visitor.visit_frame_type(self)
##############
# Statements #
##############
@dataclass(frozen=True, kw_only=True)
class Stmt(ABC):
location: Optional[Location] = None
@abstractmethod
def accept(self, visitor: Visitor[T]) -> T: ...
class Visitor(ABC, Generic[T]):
@abstractmethod
def visit_function(self, stmt: Function) -> T: ...
@dataclass(frozen=True)
class Function(Expr):
class Function(Stmt):
name: str
posonlyargs: list[FunctionArgument]
args: list[FunctionArgument]
kwonlyargs: list[FunctionArgument]
posonlyargs: list[Argument]
args: list[Argument]
kwonlyargs: list[Argument]
returns: Optional[MidasType]
def accept(self, visitor: Expr.Visitor[T]) -> T:
@dataclass(frozen=True, kw_only=True)
class Argument:
location: Optional[Location] = None
name: Optional[str]
type: Optional[MidasType]
def accept(self, visitor: Stmt.Visitor[T]) -> T:
return visitor.visit_function(self)
@dataclass(frozen=True)
class FunctionArgument(Expr):
name: Optional[str]
type: Optional[MidasType]
def accept(self, visitor: Expr.Visitor[T]) -> T:
return visitor.visit_function_argument(self)

View File

@@ -8,7 +8,6 @@ from midas.ast.python import (
FrameColumn,
FrameType,
Function,
FunctionArgument,
MidasType,
)
@@ -63,7 +62,7 @@ class PythonParser(ast.NodeVisitor):
returns=returns,
):
def parse_args(args_list: list[ast.arg]) -> list[FunctionArgument]:
def parse_args(args_list: list[ast.arg]) -> list[Function.Argument]:
return [self._parse_function_argument(arg) for arg in args_list]
return Function(
@@ -75,13 +74,13 @@ class PythonParser(ast.NodeVisitor):
returns=self._parse_type(returns) if returns is not None else None,
)
def _parse_function_argument(self, arg: ast.arg) -> FunctionArgument:
def _parse_function_argument(self, arg: ast.arg) -> Function.Argument:
loc: Location = Location.from_ast(arg)
name: str = arg.arg
type: Optional[MidasType] = None
if arg.annotation is not None:
type = self._parse_type(arg.annotation)
return FunctionArgument(
return Function.Argument(
location=loc,
name=name,
type=type,