# HG changeset patch # User Matthew Wild <mwild1@gmail.com> # Date 1539861110 -3600 # Node ID 439cf3bbe5f330fab60b8f330f9b688b24c4303d # Parent cb88d729e98ddbe1180ca0bf105ea7fcd14bb6b2 util.promise: Also support automatic resolution by returning a promise from an on_reject handler Originally unimplemented because it wasn't clear to me what the correct behaviour was, but the A+ spec is clear that both onFulfilled and onRejected may return a promise. diff -r cb88d729e98d -r 439cf3bbe5f3 util/promise.lua --- a/util/promise.lua Thu Oct 18 12:04:14 2018 +0100 +++ b/util/promise.lua Thu Oct 18 12:11:50 2018 +0100 @@ -46,7 +46,9 @@ local function _reject(e) if resolved then return; end resolved = true; - if promise_settle(p, "rejected", next_rejected, p._pending_on_rejected, e) then + if is_promise(e) then + e:next(new_resolve_functions(p)); + elseif promise_settle(p, "rejected", next_rejected, p._pending_on_rejected, e) then p.reason = e; end end