FindProxyForURL Beta

PAC-E008 · potentially-infinite-loop

Loop without a reachable exit

high · Errors and robustness

A while/for/do loop whose condition is a constant truthy value and whose body contains no break, return or throw. It can never terminate.

Why it matters

while (true) or for (;;) without break or return inside is the static form of PAC-E007. It is usually a leftover from debugging or a mis-edited retry loop. Unlike most PAC bugs this one does not fail open; it stalls proxy resolution for the whole browser.

How to fix

Delete the loop or add a terminating condition; PAC logic rarely needs loops at all.

Examples

Bad

function FindProxyForURL(url, host) {
  while (true) {
    host = host.toLowerCase();
  }
  return "DIRECT";
}
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Good

function FindProxyForURL(url, host) {
  host = host.toLowerCase();
  return "DIRECT";
}
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Related rules

References