Will It Vibe?Blocking subprocess call inside an async function
Part of Code Quality & Syntax, which counts for 20% of the overall score. When this check fires it deducts 8 points from that category, once per scan, no matter how many places it turns up.
What it detects
subprocess.run/call/check_call/check_output block the calling thread until the child process exits, stalling the event loop for its whole lifetime.
Why it matters
subprocess.run, subprocess.call, subprocess.check_call, and subprocess.check_output all block the calling thread until the child process exits, so calling any of them inside an async function blocks the event loop for the entire lifetime of that subprocess, exactly like time.sleep() or a blocking HTTP call would. A long-running migration, build step, or shell command invoked this way can stall every other coroutine on the loop for seconds or minutes.
How to fix it
Use asyncio's own subprocess API instead: await asyncio.create_subprocess_exec(...) (or create_subprocess_shell) and then await proc.wait() or await proc.communicate(). This runs the child process without blocking the event loop while it waits.
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