We need to take the self-reference to the XHR object as soon as the request is
made. Previously, we were waiting until we got the start callback, but v8 could
(and does) drop the reference before that happens. Unfortunately, that means
we can no longer use _transfer == null to tell if we own a reference or not, so
a new boolean was added.
V8 needs our help when serializing host (e.g. a Zig dom instance) objects. We
don't currently have this implemented, so this provides the callback that throws
an error. Our wrapper returns Nothing when no callback is provided, which v8
doesn't allow (via assertion).
These new optional parameter run AFTER --wait-until, allowing the (imo) useful
combination of `--wait-until load --wait-script "report.complete === true"`.
However, if `--wait-until` IS NOT specified but `--wait-selector/script` IS,
then there is no default wait and it'll just check the selector/script. If
neither `--wait-selector` or `--wait-script/--wait-script-file` are specified
then `--wait-until` continues to default to `done`.
These waiters were added to the Runner, and the existing Action.waitForSelector
now uses the runner's version. Selector querying has been split into distinct
parse and query functions, so that we can parse once, and query on every tick.
We could potentially optimize --wait-script to compile the script once and call
it on each tick, but we'd have to detect page navigation to recompile the script
in the new context. Something I'd rather optimize separately.
These changes all better align with chrome's event ordering/timing.
There are two big changes. The first is that our internal page_navigated event,
which is kind of our heavy hitter, is sent once the header is received as
opposed to (much later) on document load. The main goal of this internal event
is to trigger the "Page.frameNavigated" CDP event which is meant to happen
once the URL is committed, which _is_ on header response.
To accommodate this earlier trigger, new explicit events for DOMContentLoaded
and load have be added.
This drastically changes the flow of events as things go from:
Start Page Navigation
Response Received
Start Frame Navigation
Response Received
End Frame Navigation
End Page Navigation
context clear + reset
DOMContentLoaded
Loaded
TO:
Start Page Navigation
Response Received
End Page Navigation
context clear + reset
Start Frame Navigation
Response Received
End Frame Navigation
DOMContentLoaded
Loaded
So not only does it remove the nesting, but it ensures that the context are
cleared and reset once the main page's navigation is locked in, and before any
frame is created.
Pierre Tachoire