Figure out which files are causing `babel-plugin-react-compiler` to output bad code and crash Vite's Rollup build

bisect_react_compiler_vite.py

import asyncio
import sys
import typing

"""

vite.config.ts has these lines:

function djb2Hash(str: string): number {
  let hash = 5381
  for (let i = 0; i < str.length; i++) {
    hash = (hash * 33) ^ str.charCodeAt(i)
  }
  return hash >>> 0 // Ensure positive integer
}

const NUMERATOR = 41
const DENOMINATOR = 256

"""


def write_constants(numerator: int, denominator: int) -> None:
    with open("vite_config/vite.config.ts") as f:
        lines = f.readlines()

    for i, line in enumerate(lines):
        if "const NUMERATOR" in line:
            lines[i] = f"const NUMERATOR = {numerator}\n"
        elif "const DENOMINATOR" in line:
            lines[i] = f"const DENOMINATOR = {denominator}\n"

    with open("vite_config/vite.config.ts", "w") as f:
        f.writelines(lines)


SUCCESS_MESSAGE = 'Export "ConfigConsumer" of module'
FAILURE_MESSAGE = "ENOENT"


async def forward_stream(
    input_stream: asyncio.StreamReader,
    output_stream: typing.IO[str],
) -> None:
    """Forward a subprocess stream to one of our output streams."""
    while not input_stream.at_eof():
        line_bytes = await input_stream.readline()
        line = line_bytes.decode()
        output_stream.write(line)
        output_stream.flush()


async def forward_and_parse_stream(
    input_stream: asyncio.StreamReader,
    output_stream: typing.IO[str],
) -> bool:
    """Process stderr and look for signs of success or failure.

    Return True if we see a line indicating successful startup.
    Return False if we see an error message.

    """
    success: typing.Optional[bool] = None

    while True:
        line_bytes = await input_stream.readline()
        line = line_bytes.decode()

        # Forward each line of the process's stdout to our stdout
        output_stream.write(line)
        output_stream.flush()

        # Look for messages which indicate success or failure
        if success is None:
            if SUCCESS_MESSAGE in line:
                success = True
            elif FAILURE_MESSAGE in line:
                success = False

        if success is not None:
            return success


async def run_build(
    stdout: typing.IO[str],
    stderr: typing.IO[str],
) -> bool:
    process = await asyncio.create_subprocess_exec(
        "/opt/homebrew/bin/pnpm",
        "vite:build",
        stdout=asyncio.subprocess.PIPE,
        stderr=asyncio.subprocess.PIPE,
    )
    assert process.stdout is not None
    assert process.stderr is not None

    stdout_forward = asyncio.create_task(forward_stream(process.stdout, stdout))
    success = await forward_and_parse_stream(process.stderr, stderr)

    process.terminate()
    await process.wait()
    await stdout_forward
    return success


async def bisect():

    nmodules = 27218

    numerator = 41
    denominator = 128

    # numerator = 297
    # denominator = 512

    with open("stdout.txt", "w") as stdout:
        with open("stderr.txt", "w") as stderr:
            while denominator < nmodules * 2:
                write_constants(numerator, denominator)
                print(f"jeff running: {numerator}/{denominator}...")
                success = await run_build(stdout, stderr)

                status_emoji = "✅" if success else "❌"
                print(f"jeff result: {numerator}/{denominator}: {status_emoji}")

                if success:
                    numerator += denominator // 2
                    numerator = numerator % denominator
                else:
                    denominator *= 2


if __name__ == "__main__":
    asyncio.run(bisect())