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Test Info:
/* Any copyright is dedicated to the Public Domain.
"use strict";
/**
* Test initial target resources are correctly retrieved even when several calls
* to watchResources are made simultaneously.
*
* This checks a race condition which occurred when calling watchResources
* simultaneously. This made the "second" call to watchResources miss existing
* resources (in case those are emitted from the target instead of the watcher).
*/
add_task(async function () {
// Disable the preloaded process as it creates processes intermittently
// which forces the emission of RDP requests we aren't correctly waiting for.
await pushPref("dom.ipc.processPrelaunch.enabled", false);
const { client, resourceCommand, targetCommand } =
await initMultiProcessResourceCommand();
const expectedPlatformMessage = "expectedMessage";
info("Log a message *before* calling ResourceCommand.watchResources");
Services.console.logStringMessage(expectedPlatformMessage);
info("Call watchResources from 2 separate call sites consecutively");
// Empty onAvailable callback for CSS MESSAGES, we only want to check that
// the second resource we watch correctly provides existing resources.
const onCssMessageAvailable = () => {};
// First call to watchResources.
// We do not await on `watchPromise1` here, in order to simulate simultaneous
// calls to watchResources (which could come from 2 separate modules in a real
// scenario).
const initialWatchPromise = resourceCommand.watchResources(
[resourceCommand.TYPES.CSS_MESSAGE],
{
onAvailable: onCssMessageAvailable,
}
);
// `waitForNextResource` will trigger another call to `watchResources`.
const { onResource: onMessageReceived } =
await resourceCommand.waitForNextResource(
resourceCommand.TYPES.PLATFORM_MESSAGE,
{
ignoreExistingResources: false,
predicate: r => r.message === expectedPlatformMessage,
}
);
info("Waiting for the expected message to be received");
await onMessageReceived;
ok(true, "All the expected messages were received");
info("Wait for the other watchResources promise to finish");
await initialWatchPromise;
// Unwatch all resources.
resourceCommand.unwatchResources([resourceCommand.TYPES.CSS_MESSAGE], {
onAvailable: onCssMessageAvailable,
});
Services.console.reset();
targetCommand.destroy();
await client.close();
});