var inOurTests bool // whether we're in our own tests

// shouldPanicOnCopyError reports whether the reverse proxy should
// panic with http.ErrAbortHandler. This is the right thing to do by
// default, but Go 1.10 and earlier did not, so existing unit tests
// weren't expecting panics. Only panic in our own tests, or when
// running under the HTTP server.
func shouldPanicOnCopyError(req *http.Request) bool {
	if inOurTests {