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// |reftest| async
// Copyright (C) 2026 Caio Lima. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-moduleevaluation
description: >
Dynamic import of a fulfilled member of an errored async cycle rejects with
the recorded evaluation error
info: |
When the top-level-await cycle {A, B, C} rejects (B throws after its await),
only B and its async parent modules (X and main) record the evaluation
error. A and C had already finished executing and stay EVALUATED with an
empty [[EvaluationError]]. The cycle is first evaluated starting from B (the
first dependency of main), so B is the [[CycleRoot]] of {A, B, C} and, not
being an evaluation entry point itself, it has no [[TopLevelCapability]].
A later dynamic import of C redirects to its [[CycleRoot]] B, whose
[[Status]] is EVALUATED with a non-empty [[EvaluationError]] and no
[[TopLevelCapability]]. Evaluate() is well-defined on such case, thus a
fresh capability is created and installed as B's [[TopLevelCapability]],
InnerModuleEvaluation returns the recorded [[EvaluationError]], and the
capability is rejected with it. This makes the import of C reject with
the same error with which the cycle originally failed.
Evaluate ( )
1. ...
1. If _module_.[[Status]] is either EVALUATING-ASYNC or EVALUATED, then
1. If module.[[CycleRoot]] is not empty, then
1. Set _module_ to _module_.[[CycleRoot]].
1. Else,
1. ...
1. If _module_.[[TopLevelCapability]] is not EMPTY, then
1. Return _module_.[[TopLevelCapability]].[[Promise]].
1. Let _stack_ be a new empty List.
1. Let _capability_ be ! NewPromiseCapability(%Promise%).
1. Set _module_.[[TopLevelCapability]] to _capability_.
1. Let _result_ be Completion(InnerModuleEvaluation(_module_, _stack_, 0)).
1. If _result_ is an abrupt completion, then
1. ...
1. Perform ! Call(_capability_.[[Reject]], *undefined*, « _result_.[[Value]] »).
1. ...
1. Return _capability_.[[Promise]].
InnerModuleEvaluation ( _module_, _stack_, _index_ )
1. ...
1. If _module_.[[Status]] is either EVALUATING-ASYNC or EVALUATED, then
1. If _module_.[[EvaluationError]] is EMPTY, return _index_.
1. Return ? _module_.[[EvaluationError]].
1. ...
flags: [async]
features: [top-level-await, dynamic-import]
includes: [asyncHelpers.js]
---*/
asyncTest(async function () {
var errorFromMain = null;
try {
await import("./import-fulfilled-member-of-errored-cycle-main_FIXTURE.js");
} catch (err) {
errorFromMain = err;
}
assert.notSameValue(errorFromMain, null, "The import of main should reject");
assert.sameValue(
errorFromMain instanceof Error,
true,
"The import of main should reject with the error thrown in B"
);
assert.sameValue(errorFromMain.message, "async error in B");
var errorFromC = null;
try {
await import("./import-fulfilled-member-of-errored-cycle-c_FIXTURE.js");
} catch (err) {
errorFromC = err;
}
assert.notSameValue(errorFromC, null, "The import of C should reject");
assert.sameValue(
errorFromC,
errorFromMain,
"The import of C should reject with the [[EvaluationError]] recorded for the cycle root B"
);
});