"""Compile mypy using mypyc with trace logging enabled, and collect a trace.

The trace log can be used to analyze low-level performance bottlenecks.

By default does a self check as the workload.

This works on all supported platforms, unlike some of our other performance tools.

"""

from __future__ import annotations

import argparse

import glob

import os

import shutil

import subprocess

import sys

import time

from perf_compare import build_mypy, clone

# Generated files, including binaries, go under this directory to avoid overwriting user state.

TARGET_DIR = "mypy.log_trace.tmpdir"

def perform_type_check(target_dir: str, code: str | None) -> None:

cache_dir = os.path.join(target_dir, ".mypy_cache")

if os.path.exists(cache_dir):

shutil.rmtree(cache_dir)

args = []

if code is None:

args.extend(["--config-file", "mypy_self_check.ini"])

for pat in "mypy/*.py", "mypy/*/*.py", "mypyc/*.py", "mypyc/test/*.py":

args.extend(glob.glob(pat))

else:

args.extend(["-c", code])

check_cmd = ["python", "-m", "mypy"] + args

t0 = time.time()

subprocess.run(check_cmd, cwd=target_dir, check=True)

elapsed = time.time() - t0

print(f"{elapsed:.2f}s elapsed")

def main() -> None:

parser = argparse.ArgumentParser(

description="Compile mypy and collect a trace log while type checking (by default, self check)."

)

parser.add_argument(

"--multi-file",

action="store_true",

help="compile mypy into one C file per module (to reduce RAM use during compilation)",

)

parser.add_argument(

"--skip-compile", action="store_true", help="use compiled mypy from previous run"

)

parser.add_argument(

"-c",

metavar="CODE",

default=None,

type=str,

help="type check Python code fragment instead of mypy self-check",

)

args = parser.parse_args()

multi_file: bool = args.multi_file

skip_compile: bool = args.skip_compile

code: str | None = args.c

target_dir = TARGET_DIR

if not skip_compile:

clone(target_dir, "HEAD")

print(f"Building mypy in {target_dir} with trace logging enabled...")

build_mypy(target_dir, multi_file, log_trace=True, opt_level="0")

elif not os.path.isdir(target_dir):

sys.exit("error: Can't find compile mypy from previous run -- can't use --skip-compile")

perform_type_check(target_dir, code)

trace_fnam = os.path.join(target_dir, "mypyc_trace.txt")

print(f"Generated event trace log in {trace_fnam}")

if __name__ == "__main__":

main()