from __future__ import annotations

import re

from librt.internal import ReadBuffer

from mypy import errorcodes as codes

from mypy.cache import read_int

from mypy.errors import Errors

from mypy.nodes import FileRawData, MypyFile, ParseError

from mypy.options import Options

def parse(

source: str | bytes,

fnam: str,

module: str | None,

errors: Errors,

options: Options,

file_exists: bool,

eager: bool = False,

) -> MypyFile:

"""Parse a source file, without doing any semantic analysis.

Return the parse tree, use the errors object to report parse errors.

The python_version (major, minor) option determines the Python syntax variant.

New parser returns empty tree with serialized data. To get the full tree and

the parse errors, use eager=True.

"""

if options.native_parser:

# Native parser only works with actual files on disk

# Fall back to fastparse for in-memory source or non-existent files

if file_exists:

import mypy.nativeparse

ignore_errors = options.ignore_errors or fnam in errors.ignored_files

# If errors are ignored, we can drop many function bodies to speed up type checking.

strip_function_bodies = ignore_errors and not options.preserve_asts

tree, _, _ = mypy.nativeparse.native_parse(

fnam, options, skip_function_bodies=strip_function_bodies

)

# Set is_stub based on file extension

tree.is_stub = fnam.endswith(".pyi")

# Note: tree.imports is populated directly by load_from_raw() with deserialized

# import metadata, so we don't need to collect imports via AST traversal

if eager and tree.raw_data is not None:

tree = load_from_raw(fnam, module, tree.raw_data, errors, options)

return tree

# Fall through to fastparse for non-existent files

if options.transform_source is not None:

source = options.transform_source(source)

import mypy.fastparse

return mypy.fastparse.parse(source, fnam=fnam, module=module, errors=errors, options=options)

def load_from_raw(

fnam: str,

module: str | None,

raw_data: FileRawData,

errors: Errors,

options: Options,

imports_only: bool = False,

) -> MypyFile:

"""Load AST from parsed binary data and report stored errors.

If imports_only is true, only deserialize imports and return a mostly

empty AST.

"""

from mypy.nativeparse import State, deserialize_imports, read_statements

state = State(options)

if imports_only:

defs = []

else:

data = ReadBuffer(raw_data.defs)

n = read_int(data)

defs = read_statements(state, data, n)

imports = deserialize_imports(raw_data.imports)

tree = MypyFile(defs, imports)

tree.path = fnam

tree.ignored_lines = raw_data.ignored_lines

tree.is_partial_stub_package = raw_data.is_partial_stub_package

tree.uses_template_strings = raw_data.uses_template_strings

tree.is_stub = fnam.endswith(".pyi")

if module is not None:

tree._fullname = module

# Report parse errors, this replicates the logic in parse().

all_errors = raw_data.raw_errors + state.errors

errors.set_file(fnam, module, options=options)

for error in all_errors:

# Note we never raise in this function, so it should not be called in coordinator.

report_parse_error(error, errors)

if imports_only:

# Preserve raw data when only de-serializing imports, it will be sent to

# the parallel workers.

tree.raw_data = raw_data

return tree

def report_parse_error(error: ParseError, errors: Errors) -> None:

message = error["message"]

# Standardize error message by capitalizing the first word

message = re.sub(r"^(\s*\w)", lambda m: m.group(1).upper(), message)

# Respect blocker status from error, default to True for syntax errors

is_blocker = error.get("blocker", True)

error_code = error.get("code")

if error_code is None:

error_code = codes.SYNTAX

else:

# Fallback to [syntax] for backwards compatibility.

error_code = codes.error_codes.get(error_code) or codes.SYNTAX

errors.report(error["line"], error["column"], message, blocker=is_blocker, code=error_code)