Does the file exist?
This returns true for regular files and FIFOs. It returns false for directories. Note that a race condition can occur where the file is deleted or renamed after this is called but before you open it.
This does a system call to check if the file exists, which can be slow.
If using this in an HTTP server, it's faster to instead use return new Response(Bun.file(path)) and then an error handler to handle exceptions.
Instead of checking for a file's existence and then performing the operation, it is faster to just perform the operation and handle the error.
For empty Blob, this always returns true.