Fix Firefox compatibility #160
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It turns out that the original code was relying on V8 specific scoping behavior. The value of the argument `initialSyncDepth` was being set to `1` even when the other arguments inside `runBatch` were being evaluated and eventually calling `runBatch` again. So if I were do make a rough trace: 1. <some function> 2. call to `runBatch` with `initialSyncDepth` set to `1` 3. evaluation of `firstBath` argument of `runBatch` 4. <some code> 5. another call to `runBatch` with no `initialSyncDepth` set ^ here is where the difference manifests, in Firefox the value of `initialSyncDepth` as seen by the nested call to `runBatch` will be `undefined`. However in V8 it will be `1` as the call to `runBatch` in 2 is still in progress technically. This difference would lead to desync between the server side and the frontend JS code, which manifests as "spinning" in a tight loop as the frontend is trying to fetch an event that doesn't exist. Signed-off-by: magic_rb <magic_rb@redalder.org>
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It turns out that the original code was relying on V8 specific scoping behavior. The value of the argument
initialSyncDepthwas being set to1even when the other arguments insiderunBatchwere being evaluated and eventually callingrunBatchagain. So if I were do make a rough trace:<some function>runBatchwithinitialSyncDepthset to1firstBatchargument ofrunBatch<some code>runBatchwith noinitialSyncDepthset^ here is where the difference manifests, in Firefox the value of
initialSyncDepthas seen by the nested call torunBatchwill beundefined. However in V8 it will be1as the call torunBatchin 2 is still in progress technically.This difference would lead to desync between the server side and the frontend JS code, which manifests as "spinning" in a tight loop as the frontend is trying to fetch an event that doesn't exist.
Properly fixes #54 and maybe also #64, while also retaining V8 compatibility as far as I can tell.
I tracked this down by running the same JSaddle program in both Firefox and ungoogled-chromium and stepping both in tandem with the respective debuggers until i found a difference.