@dash0/sdk-web/dist/modules/instrumentations/errors/async-function-wrapping.js

Dash0's Web SDK to collect telemetry from end-users' web browsers

const WRAPPED_EVENT_HANDLERS_ORIGINAL_FUNCTION_STORAGE_KEY = "__dash0OriginalFunctions";
// Asynchronous function wrapping: The process of wrapping a listener which goes into one function, e.g.
//
//  - EventTarget#addEventListener
//  - EventEmitter#on
//
// and is removed via another function, e.g.
//
//  - EventTarget#removeEventListener
//  - EventEmitter#off
//
// What is complicated about this, is that these methods identify registered listeners by function reference.
// When we wrap a function, we naturally change the reference. We must therefore keep track of which
// original function belongs to what wrapped function.
//
// This file provides helpers that help in the typical cases. It is removed from all browser specific APIs
// in order to allow simple unit test execution.
//
// Note that this file follows the behavior outlined in DOM specification. Among others, this means that it is not
// possible to register the same listener twice.
// http://dom.spec.whatwg.org
export function addWrappedFunction(storageTarget, wrappedFunction, valuesForEqualityCheck) {
    if (!storageTarget)
        return wrappedFunction;
    const storage = (storageTarget[WRAPPED_EVENT_HANDLERS_ORIGINAL_FUNCTION_STORAGE_KEY] =
        storageTarget[WRAPPED_EVENT_HANDLERS_ORIGINAL_FUNCTION_STORAGE_KEY] || []);
    const index = findInStorage(storageTarget, valuesForEqualityCheck);
    if (index !== -1) {
        // already registered. Do not allow re-registration
        return storage[index].wrappedFunction;
    }
    storage.push({
        wrappedFunction,
        valuesForEqualityCheck,
    });
    return wrappedFunction;
}
function findInStorage(storageTarget, valuesForEqualityCheck) {
    const storage = storageTarget[WRAPPED_EVENT_HANDLERS_ORIGINAL_FUNCTION_STORAGE_KEY];
    for (let i = 0; i < storage.length; i++) {
        const storageItem = storage[i];
        if (matchesEqualityCheck(storageItem.valuesForEqualityCheck, valuesForEqualityCheck)) {
            return i;
        }
    }
    return -1;
}
export function popWrappedFunction(storageTarget, valuesForEqualityCheck, fallback) {
    const storage = storageTarget?.[WRAPPED_EVENT_HANDLERS_ORIGINAL_FUNCTION_STORAGE_KEY];
    if (storage == null) {
        return fallback;
    }
    const index = findInStorage(storageTarget, valuesForEqualityCheck);
    if (index === -1) {
        return fallback;
    }
    const storageItem = storage[index];
    storage.splice(index, 1);
    return storageItem.wrappedFunction;
}
function matchesEqualityCheck(valuesForEqualityCheckA, valuesForEqualityCheckB) {
    if (valuesForEqualityCheckA.length !== valuesForEqualityCheckB.length) {
        return false;
    }
    for (let i = 0; i < valuesForEqualityCheckA.length; i++) {
        if (valuesForEqualityCheckA[i] !== valuesForEqualityCheckB[i]) {
            return false;
        }
    }
    return true;
}
export function addWrappedDomEventListener(storageTarget, wrappedFunction, eventName, eventListener, optionsOrCapture) {
    return addWrappedFunction(storageTarget, wrappedFunction, getDomEventListenerValuesForEqualityCheck(eventName, eventListener, optionsOrCapture));
}
function getDomEventListenerValuesForEqualityCheck(eventName, eventListener, optionsOrCapture) {
    return [eventName, eventListener, getDomEventListenerCaptureValue(optionsOrCapture)];
}
export function getDomEventListenerCaptureValue(optionsOrCapture) {
    // > Let capture, passive, and once be the result of flattening more options.
    // https://dom.spec.whatwg.org/#dom-eventtarget-addeventlistener
    //
    // > To flatten more options, run these steps:
    // > 1. Let capture be the result of flattening options.
    // https://dom.spec.whatwg.org/#event-flatten-more
    //
    // > To flatten options, run these steps:
    // > 1. If options is a boolean, then return options.
    // > 2. Return options’s capture.
    // https://dom.spec.whatwg.org/#concept-flatten-options
    //
    // > dictionary EventListenerOptions {
    // >   boolean capture = false;
    // > };
    // https://dom.spec.whatwg.org/#dom-eventlisteneroptions-capture
    if (optionsOrCapture == null) {
        return false;
    }
    else if (typeof optionsOrCapture === "object") {
        return Boolean(optionsOrCapture.capture);
    }
    return Boolean(optionsOrCapture);
}
export function popWrappedDomEventListener(storageTarget, eventName, eventListener, optionsOrCapture, fallback) {
    return popWrappedFunction(storageTarget, getDomEventListenerValuesForEqualityCheck(eventName, eventListener, optionsOrCapture), fallback);
}