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When a process running in a separate go-routine, e.g., a fetch request is represented by a promise in JS, the result of the process is enqueued on the task queue of the main go routine. However, converting the result from a native Go value to a JavaScript value should have occurred in the main go-routine, not the concurrent task. This could cause concurrent calls to the same JavaScript context, which isn't allowed.
WalkthroughThis PR introduces a scoped clock execution model: Possibly related PRs
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| func (c *Clock) enter() { c.stack++ } | ||
| func (c *Clock) exit() error { | ||
| c.stack-- | ||
| if c.stack > 0 { | ||
| return nil | ||
| } | ||
| return c.tick() | ||
| } |
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🧹 Nitpick | 🔵 Trivial
Consider adding a defensive check for unbalanced calls.
If exit() is ever called without a matching enter() (e.g., due to a future refactoring mistake), stack would become negative and tick() would still run. While the current code correctly pairs these via Do(), a defensive check could help catch bugs early during development.
🛡️ Optional: Add defensive assertion
func (c *Clock) enter() { c.stack++ }
func (c *Clock) exit() error {
c.stack--
+ if c.stack < 0 {
+ panic("gost-dom/clock: exit() called without matching enter()")
+ }
if c.stack > 0 {
return nil
}
return c.tick()
}📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| func (c *Clock) enter() { c.stack++ } | |
| func (c *Clock) exit() error { | |
| c.stack-- | |
| if c.stack > 0 { | |
| return nil | |
| } | |
| return c.tick() | |
| } | |
| func (c *Clock) enter() { c.stack++ } | |
| func (c *Clock) exit() error { | |
| c.stack-- | |
| if c.stack < 0 { | |
| panic("gost-dom/clock: exit() called without matching enter()") | |
| } | |
| if c.stack > 0 { | |
| return nil | |
| } | |
| return c.tick() | |
| } |
| // Tick runs all tasks scheduled for immediate execution. This is synonymous | ||
| // with calling Advance(0). | ||
| func (c *Clock) Tick() error { return c.Advance(0) } | ||
| func (c *Clock) tick() error { return c.Advance(0) } |
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🧹 Nitpick | 🔵 Trivial
Minor: Update comment to reflect the method is now private.
The comment still describes Tick as if it were a public API entry point. Since it's now private (tick), consider updating the comment to reflect its internal nature, or removing it since callers should use Do() instead.
📝 Suggested comment update
-// Tick runs all tasks scheduled for immediate execution. This is synonymous
-// with calling Advance(0).
+// tick runs all tasks scheduled for immediate execution (equivalent to Advance(0)).
+// This is called internally by exit() when the outermost Do() completes.
func (c *Clock) tick() error { return c.Advance(0) }| return m.ctx.do(func() error { | ||
| m.ctx.logger().Debug("Evaluate module", "vm", m.ctx.vm) | ||
| p := m.record.Evaluate(m.ctx.vm) | ||
|
|
||
| if p.State() != sobek.PromiseStateFulfilled { | ||
| return p.Result().Export().(error) | ||
| } | ||
| return m.ctx.tick() | ||
| if p.State() != sobek.PromiseStateFulfilled { | ||
| res := p.Result().Export() | ||
| err, ok := res.(error) | ||
| if !ok { | ||
| err = fmt.Errorf("run module: %v", res) | ||
| } | ||
| return err | ||
| } | ||
| return nil | ||
| }) |
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Pending promise incorrectly treated as error—module evaluation does not await promise settlement.
The promise state is checked synchronously within Clock.Do() before microtasks are drained. For modules with top-level await (which return a pending promise), the check at line 24 will treat PromiseStatePending as a failure.
Compare to the V8 implementation (scripting/v8engine/module.go), which explicitly awaits the promise via awaitPromise() to allow settlement before returning. The Sobek implementation lacks this promise-awaiting mechanism and will reject async modules.
Recommend adding explicit promise settlement logic similar to V8, or ensuring Clock.Do() drains microtasks before the state check occurs.
1 participant
When a process running in a separate go-routine, e.g., a fetch request is represented by a promise in JS, the result of the process is enqueued on the task queue of the main go routine.
However, converting the result from a native Go value to a JavaScript value should have occurred in the main go-routine, not the concurrent task. This could cause concurrent calls to the same JavaScript context, which isn't allowed.