Revisit suspending the running execution context for modules, fixes #143 #175
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This is the part of the spec that I always understood least, so I'm hoping @guybedford understands it :) |
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I'm also not 100% clear on this, but there is no Perhaps we can get another reviewer on this. |
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I guess the question is, does this line of effectively take the place of the suspend the running execution context line? I do see examples in the spec though of that line being called after suspending the current execution context, for example see https://tc39.es/ecma262/#await-fulfilled where in step 4 the current context is suspended just before calling a push. |
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That was my reading of the spec, but it might be wrong. @littledan who would be the best person to ask about this? |
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After chatting with @guybedford it looks like the existing spec is correct. |
| 1. <del>Let _moduleContext_ be _module_.[[Context]].</del> | ||
| 1. <del>Push _moduleContext_ onto the execution context stack; moduleContext is now the running execution context.</del> | ||
| 1. <del>Let _result_ be the result of evaluating _module_.[[ECMAScriptCode]].</del> | ||
| 1. <del>Suspend moduleContext and remove it from the execution context stack.</del> | ||
| 1. <del>Resume the context that is now on the top of the execution context stack as the running execution context.</del> | ||
| 1. <del>Return Completion(_result_). </del> | ||
| 1. <ins>If _module_.[[Async]] is *false*, then</ins> | ||
| 1. <ins>Suspend the currently running execution context.</ins> |
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this isn't quite right
Tries to address #143 -- my reading of the spec is that, we should not be suspending the execution context in the case of an async module. The async module context plays the same role as the copy of the running context,
asyncContextdoes in AsyncFunctionStart, and the running context in that case is not suspended. I believe it would be wrong to suspend in the case of modules, as execution should continue and the module context itself should be treated as a promise from my understanding.