"use strict"; var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) { function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); } return new (P || (P = Promise))(function (resolve, reject) { function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } } function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } } function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); } step((generator = generator.apply(thisArg, _arguments || [])).next()); }); }; import { ForkEvent, Provider } from "@ethersproject/abstract-provider"; import { BigNumber } from "@ethersproject/bignumber"; import { arrayify, hexDataLength, hexlify, hexValue, isHexString } from "@ethersproject/bytes"; import { namehash } from "@ethersproject/hash"; import { getNetwork } from "@ethersproject/networks"; import { defineReadOnly, getStatic, resolveProperties } from "@ethersproject/properties"; import { toUtf8String } from "@ethersproject/strings"; import { poll } from "@ethersproject/web"; import { Logger } from "@ethersproject/logger"; import { version } from "./_version"; const logger = new Logger(version); import { Formatter } from "./formatter"; ////////////////////////////// // Event Serializeing function checkTopic(topic) { if (topic == null) { return "null"; } if (hexDataLength(topic) !== 32) { logger.throwArgumentError("invalid topic", "topic", topic); } return topic.toLowerCase(); } function serializeTopics(topics) { // Remove trailing null AND-topics; they are redundant topics = topics.slice(); while (topics.length > 0 && topics[topics.length - 1] == null) { topics.pop(); } return topics.map((topic) => { if (Array.isArray(topic)) { // Only track unique OR-topics const unique = {}; topic.forEach((topic) => { unique[checkTopic(topic)] = true; }); // The order of OR-topics does not matter const sorted = Object.keys(unique); sorted.sort(); return sorted.join("|"); } else { return checkTopic(topic); } }).join("&"); } function deserializeTopics(data) { if (data === "") { return []; } return data.split(/&/g).map((topic) => { return topic.split("|").map((topic) => { return ((topic === "null") ? null : topic); }); }); } function getEventTag(eventName) { if (typeof (eventName) === "string") { eventName = eventName.toLowerCase(); if (hexDataLength(eventName) === 32) { return "tx:" + eventName; } if (eventName.indexOf(":") === -1) { return eventName; } } else if (Array.isArray(eventName)) { return "filter:*:" + serializeTopics(eventName); } else if (ForkEvent.isForkEvent(eventName)) { logger.warn("not implemented"); throw new Error("not implemented"); } else if (eventName && typeof (eventName) === "object") { return "filter:" + (eventName.address || "*") + ":" + serializeTopics(eventName.topics || []); } throw new Error("invalid event - " + eventName); } ////////////////////////////// // Helper Object function getTime() { return (new Date()).getTime(); } ////////////////////////////// // Provider Object /** * EventType * - "block" * - "pending" * - "error" * - filter * - topics array * - transaction hash */ export class Event { constructor(tag, listener, once) { defineReadOnly(this, "tag", tag); defineReadOnly(this, "listener", listener); defineReadOnly(this, "once", once); } get event() { switch (this.type) { case "tx": return this.hash; case "filter": return this.filter; } return this.tag; } get type() { return this.tag.split(":")[0]; } get hash() { const comps = this.tag.split(":"); if (comps[0] !== "tx") { return null; } return comps[1]; } get filter() { const comps = this.tag.split(":"); if (comps[0] !== "filter") { return null; } const address = comps[1]; const topics = deserializeTopics(comps[2]); const filter = {}; if (topics.length > 0) { filter.topics = topics; } if (address && address !== "*") { filter.address = address; } return filter; } pollable() { return (this.tag.indexOf(":") >= 0 || this.tag === "block" || this.tag === "pending"); } } let defaultFormatter = null; let nextPollId = 1; export class BaseProvider extends Provider { constructor(network) { logger.checkNew(new.target, Provider); super(); this.formatter = new.target.getFormatter(); if (network instanceof Promise) { defineReadOnly(this, "ready", network.then((network) => { defineReadOnly(this, "_network", network); return network; })); // Squash any "unhandled promise" errors; that do not need to be handled this.ready.catch((error) => { }); } else { const knownNetwork = getStatic((new.target), "getNetwork")(network); if (knownNetwork) { defineReadOnly(this, "_network", knownNetwork); defineReadOnly(this, "ready", Promise.resolve(this._network)); } else { logger.throwArgumentError("invalid network", "network", network); } } this._maxInternalBlockNumber = -1024; this._lastBlockNumber = -2; // Events being listened to this._events = []; this._pollingInterval = 4000; this._emitted = { block: -2 }; this._fastQueryDate = 0; } static getFormatter() { if (defaultFormatter == null) { defaultFormatter = new Formatter(); } return defaultFormatter; } static getNetwork(network) { return getNetwork((network == null) ? "homestead" : network); } _getInternalBlockNumber(maxAge) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const internalBlockNumber = this._internalBlockNumber; if (maxAge > 0 && this._internalBlockNumber) { const result = yield internalBlockNumber; if ((getTime() - result.respTime) <= maxAge) { return result.blockNumber; } } const reqTime = getTime(); this._internalBlockNumber = this.perform("getBlockNumber", {}).then((blockNumber) => { const respTime = getTime(); blockNumber = BigNumber.from(blockNumber).toNumber(); if (blockNumber < this._maxInternalBlockNumber) { blockNumber = this._maxInternalBlockNumber; } this._maxInternalBlockNumber = blockNumber; this._setFastBlockNumber(blockNumber); // @TODO: Still need this? return { blockNumber, reqTime, respTime }; }); return (yield this._internalBlockNumber).blockNumber; }); } poll() { return __awaiter(this, void 0, void 0, function* () { const pollId = nextPollId++; this.emit("willPoll", pollId); // Track all running promises, so we can trigger a post-poll once they are complete const runners = []; const blockNumber = yield this._getInternalBlockNumber(100 + this.pollingInterval / 2); this._setFastBlockNumber(blockNumber); // If the block has not changed, meh. if (blockNumber === this._lastBlockNumber) { return; } // First polling cycle, trigger a "block" events if (this._emitted.block === -2) { this._emitted.block = blockNumber - 1; } // Notify all listener for each block that has passed for (let i = this._emitted.block + 1; i <= blockNumber; i++) { this.emit("block", i); } // The emitted block was updated, check for obsolete events if (this._emitted.block !== blockNumber) { this._emitted.block = blockNumber; Object.keys(this._emitted).forEach((key) => { // The block event does not expire if (key === "block") { return; } // The block we were at when we emitted this event const eventBlockNumber = this._emitted[key]; // We cannot garbage collect pending transactions or blocks here // They should be garbage collected by the Provider when setting // "pending" events if (eventBlockNumber === "pending") { return; } // Evict any transaction hashes or block hashes over 12 blocks // old, since they should not return null anyways if (blockNumber - eventBlockNumber > 12) { delete this._emitted[key]; } }); } // First polling cycle if (this._lastBlockNumber === -2) { this._lastBlockNumber = blockNumber - 1; } // Find all transaction hashes we are waiting on this._events.forEach((event) => { switch (event.type) { case "tx": { const hash = event.hash; let runner = this.getTransactionReceipt(hash).then((receipt) => { if (!receipt || receipt.blockNumber == null) { return null; } this._emitted["t:" + hash] = receipt.blockNumber; this.emit(hash, receipt); return null; }).catch((error) => { this.emit("error", error); }); runners.push(runner); break; } case "filter": { const filter = event.filter; filter.fromBlock = this._lastBlockNumber + 1; filter.toBlock = blockNumber; const runner = this.getLogs(filter).then((logs) => { if (logs.length === 0) { return; } logs.forEach((log) => { this._emitted["b:" + log.blockHash] = log.blockNumber; this._emitted["t:" + log.transactionHash] = log.blockNumber; this.emit(filter, log); }); }).catch((error) => { this.emit("error", error); }); runners.push(runner); break; } } }); this._lastBlockNumber = blockNumber; Promise.all(runners).then(() => { this.emit("didPoll", pollId); }); return null; }); } resetEventsBlock(blockNumber) { this._lastBlockNumber = blockNumber - 1; if (this.polling) { this.poll(); } } get network() { return this._network; } getNetwork() { return this.ready; } get blockNumber() { return this._fastBlockNumber; } get polling() { return (this._poller != null); } set polling(value) { setTimeout(() => { if (value && !this._poller) { this._poller = setInterval(this.poll.bind(this), this.pollingInterval); this.poll(); } else if (!value && this._poller) { clearInterval(this._poller); this._poller = null; } }, 0); } get pollingInterval() { return this._pollingInterval; } set pollingInterval(value) { if (typeof (value) !== "number" || value <= 0 || parseInt(String(value)) != value) { throw new Error("invalid polling interval"); } this._pollingInterval = value; if (this._poller) { clearInterval(this._poller); this._poller = setInterval(() => { this.poll(); }, this._pollingInterval); } } _getFastBlockNumber() { const now = getTime(); // Stale block number, request a newer value if ((now - this._fastQueryDate) > 2 * this._pollingInterval) { this._fastQueryDate = now; this._fastBlockNumberPromise = this.getBlockNumber().then((blockNumber) => { if (this._fastBlockNumber == null || blockNumber > this._fastBlockNumber) { this._fastBlockNumber = blockNumber; } return this._fastBlockNumber; }); } return this._fastBlockNumberPromise; } _setFastBlockNumber(blockNumber) { // Older block, maybe a stale request if (this._fastBlockNumber != null && blockNumber < this._fastBlockNumber) { return; } // Update the time we updated the blocknumber this._fastQueryDate = getTime(); // Newer block number, use it if (this._fastBlockNumber == null || blockNumber > this._fastBlockNumber) { this._fastBlockNumber = blockNumber; this._fastBlockNumberPromise = Promise.resolve(blockNumber); } } // @TODO: Add .poller which must be an event emitter with a 'start', 'stop' and 'block' event; // this will be used once we move to the WebSocket or other alternatives to polling waitForTransaction(transactionHash, confirmations, timeout) { return __awaiter(this, void 0, void 0, function* () { if (confirmations == null) { confirmations = 1; } const receipt = yield this.getTransactionReceipt(transactionHash); // Receipt is already good if ((receipt ? receipt.confirmations : 0) >= confirmations) { return receipt; } // Poll until the receipt is good... return new Promise((resolve, reject) => { let timer = null; let done = false; const handler = (receipt) => { if (receipt.confirmations < confirmations) { return; } if (timer) { clearTimeout(timer); } if (done) { return; } done = true; this.removeListener(transactionHash, handler); resolve(receipt); }; this.on(transactionHash, handler); if (typeof (timeout) === "number" && timeout > 0) { timer = setTimeout(() => { if (done) { return; } timer = null; done = true; this.removeListener(transactionHash, handler); reject(logger.makeError("timeout exceeded", Logger.errors.TIMEOUT, { timeout: timeout })); }, timeout); if (timer.unref) { timer.unref(); } } }); }); } getBlockNumber() { return this._getInternalBlockNumber(0); } getGasPrice() { return __awaiter(this, void 0, void 0, function* () { yield this.ready; return BigNumber.from(yield this.perform("getGasPrice", {})); }); } getBalance(addressOrName, blockTag) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ address: this._getAddress(addressOrName), blockTag: this._getBlockTag(blockTag) }); return BigNumber.from(yield this.perform("getBalance", params)); }); } getTransactionCount(addressOrName, blockTag) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ address: this._getAddress(addressOrName), blockTag: this._getBlockTag(blockTag) }); return BigNumber.from(yield this.perform("getTransactionCount", params)).toNumber(); }); } getCode(addressOrName, blockTag) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ address: this._getAddress(addressOrName), blockTag: this._getBlockTag(blockTag) }); return hexlify(yield this.perform("getCode", params)); }); } getStorageAt(addressOrName, position, blockTag) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ address: this._getAddress(addressOrName), blockTag: this._getBlockTag(blockTag), position: Promise.resolve(position).then((p) => hexValue(p)) }); return hexlify(yield this.perform("getStorageAt", params)); }); } // This should be called by any subclass wrapping a TransactionResponse _wrapTransaction(tx, hash) { if (hash != null && hexDataLength(hash) !== 32) { throw new Error("invalid response - sendTransaction"); } const result = tx; // Check the hash we expect is the same as the hash the server reported if (hash != null && tx.hash !== hash) { logger.throwError("Transaction hash mismatch from Provider.sendTransaction.", Logger.errors.UNKNOWN_ERROR, { expectedHash: tx.hash, returnedHash: hash }); } // @TODO: (confirmations? number, timeout? number) result.wait = (confirmations) => __awaiter(this, void 0, void 0, function* () { // We know this transaction *must* exist (whether it gets mined is // another story), so setting an emitted value forces us to // wait even if the node returns null for the receipt if (confirmations !== 0) { this._emitted["t:" + tx.hash] = "pending"; } const receipt = yield this.waitForTransaction(tx.hash, confirmations); if (receipt == null && confirmations === 0) { return null; } // No longer pending, allow the polling loop to garbage collect this this._emitted["t:" + tx.hash] = receipt.blockNumber; if (receipt.status === 0) { logger.throwError("transaction failed", Logger.errors.CALL_EXCEPTION, { transactionHash: tx.hash, transaction: tx, receipt: receipt }); } return receipt; }); return result; } sendTransaction(signedTransaction) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const hexTx = yield Promise.resolve(signedTransaction).then(t => hexlify(t)); const tx = this.formatter.transaction(signedTransaction); try { const hash = yield this.perform("sendTransaction", { signedTransaction: hexTx }); return this._wrapTransaction(tx, hash); } catch (error) { error.transaction = tx; error.transactionHash = tx.hash; throw error; } }); } _getTransactionRequest(transaction) { return __awaiter(this, void 0, void 0, function* () { const values = yield transaction; const tx = {}; ["from", "to"].forEach((key) => { if (values[key] == null) { return; } tx[key] = Promise.resolve(values[key]).then((v) => (v ? this._getAddress(v) : null)); }); ["gasLimit", "gasPrice", "value"].forEach((key) => { if (values[key] == null) { return; } tx[key] = Promise.resolve(values[key]).then((v) => (v ? BigNumber.from(v) : null)); }); ["data"].forEach((key) => { if (values[key] == null) { return; } tx[key] = Promise.resolve(values[key]).then((v) => (v ? hexlify(v) : null)); }); return this.formatter.transactionRequest(yield resolveProperties(tx)); }); } _getFilter(filter) { return __awaiter(this, void 0, void 0, function* () { if (filter instanceof Promise) { filter = yield filter; } const result = {}; if (filter.address != null) { result.address = this._getAddress(filter.address); } ["blockHash", "topics"].forEach((key) => { if (filter[key] == null) { return; } result[key] = filter[key]; }); ["fromBlock", "toBlock"].forEach((key) => { if (filter[key] == null) { return; } result[key] = this._getBlockTag(filter[key]); }); return this.formatter.filter(yield resolveProperties(filter)); }); } call(transaction, blockTag) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ transaction: this._getTransactionRequest(transaction), blockTag: this._getBlockTag(blockTag) }); return hexlify(yield this.perform("call", params)); }); } estimateGas(transaction) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ transaction: this._getTransactionRequest(transaction) }); return BigNumber.from(yield this.perform("estimateGas", params)); }); } _getAddress(addressOrName) { return __awaiter(this, void 0, void 0, function* () { const address = yield this.resolveName(addressOrName); if (address == null) { logger.throwError("ENS name not configured", Logger.errors.UNSUPPORTED_OPERATION, { operation: `resolveName(${JSON.stringify(addressOrName)})` }); } return address; }); } _getBlock(blockHashOrBlockTag, includeTransactions) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; if (blockHashOrBlockTag instanceof Promise) { blockHashOrBlockTag = yield blockHashOrBlockTag; } // If blockTag is a number (not "latest", etc), this is the block number let blockNumber = -128; const params = { includeTransactions: !!includeTransactions }; if (isHexString(blockHashOrBlockTag, 32)) { params.blockHash = blockHashOrBlockTag; } else { try { params.blockTag = this.formatter.blockTag(yield this._getBlockTag(blockHashOrBlockTag)); if (isHexString(params.blockTag)) { blockNumber = parseInt(params.blockTag.substring(2), 16); } } catch (error) { logger.throwArgumentError("invalid block hash or block tag", "blockHashOrBlockTag", blockHashOrBlockTag); } } return poll(() => __awaiter(this, void 0, void 0, function* () { const block = yield this.perform("getBlock", params); // Block was not found if (block == null) { // For blockhashes, if we didn't say it existed, that blockhash may // not exist. If we did see it though, perhaps from a log, we know // it exists, and this node is just not caught up yet. if (params.blockHash != null) { if (this._emitted["b:" + params.blockHash] == null) { return null; } } // For block tags, if we are asking for a future block, we return null if (params.blockTag != null) { if (blockNumber > this._emitted.block) { return null; } } // Retry on the next block return undefined; } // Add transactions if (includeTransactions) { let blockNumber = null; for (let i = 0; i < block.transactions.length; i++) { const tx = block.transactions[i]; if (tx.blockNumber == null) { tx.confirmations = 0; } else if (tx.confirmations == null) { if (blockNumber == null) { blockNumber = yield this._getInternalBlockNumber(100 + 2 * this.pollingInterval); } // Add the confirmations using the fast block number (pessimistic) let confirmations = (blockNumber - tx.blockNumber) + 1; if (confirmations <= 0) { confirmations = 1; } tx.confirmations = confirmations; } } return this.formatter.blockWithTransactions(block); } return this.formatter.block(block); }), { onceBlock: this }); }); } getBlock(blockHashOrBlockTag) { return (this._getBlock(blockHashOrBlockTag, false)); } getBlockWithTransactions(blockHashOrBlockTag) { return (this._getBlock(blockHashOrBlockTag, true)); } getTransaction(transactionHash) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; if (transactionHash instanceof Promise) { transactionHash = yield transactionHash; } const params = { transactionHash: this.formatter.hash(transactionHash, true) }; return poll(() => __awaiter(this, void 0, void 0, function* () { const result = yield this.perform("getTransaction", params); if (result == null) { if (this._emitted["t:" + transactionHash] == null) { return null; } return undefined; } const tx = this.formatter.transactionResponse(result); if (tx.blockNumber == null) { tx.confirmations = 0; } else if (tx.confirmations == null) { const blockNumber = yield this._getInternalBlockNumber(100 + 2 * this.pollingInterval); // Add the confirmations using the fast block number (pessimistic) let confirmations = (blockNumber - tx.blockNumber) + 1; if (confirmations <= 0) { confirmations = 1; } tx.confirmations = confirmations; } return this._wrapTransaction(tx); }), { onceBlock: this }); }); } getTransactionReceipt(transactionHash) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; if (transactionHash instanceof Promise) { transactionHash = yield transactionHash; } const params = { transactionHash: this.formatter.hash(transactionHash, true) }; return poll(() => __awaiter(this, void 0, void 0, function* () { const result = yield this.perform("getTransactionReceipt", params); if (result == null) { if (this._emitted["t:" + transactionHash] == null) { return null; } return undefined; } // "geth-etc" returns receipts before they are ready if (result.blockHash == null) { return undefined; } const receipt = this.formatter.receipt(result); if (receipt.blockNumber == null) { receipt.confirmations = 0; } else if (receipt.confirmations == null) { const blockNumber = yield this._getInternalBlockNumber(100 + 2 * this.pollingInterval); // Add the confirmations using the fast block number (pessimistic) let confirmations = (blockNumber - receipt.blockNumber) + 1; if (confirmations <= 0) { confirmations = 1; } receipt.confirmations = confirmations; } return receipt; }), { onceBlock: this }); }); } getLogs(filter) { return __awaiter(this, void 0, void 0, function* () { yield this.ready; const params = yield resolveProperties({ filter: this._getFilter(filter) }); const logs = yield this.perform("getLogs", params); logs.forEach((log) => { if (log.removed == null) { log.removed = false; } }); return Formatter.arrayOf(this.formatter.filterLog.bind(this.formatter))(logs); }); } getEtherPrice() { return __awaiter(this, void 0, void 0, function* () { yield this.ready; return this.perform("getEtherPrice", {}); }); } _getBlockTag(blockTag) { return __awaiter(this, void 0, void 0, function* () { if (blockTag instanceof Promise) { blockTag = yield blockTag; } if (typeof (blockTag) === "number" && blockTag < 0) { if (blockTag % 1) { logger.throwArgumentError("invalid BlockTag", "blockTag", blockTag); } let blockNumber = yield this._getInternalBlockNumber(100 + 2 * this.pollingInterval); blockNumber += blockTag; if (blockNumber < 0) { blockNumber = 0; } return this.formatter.blockTag(blockNumber); } return this.formatter.blockTag(blockTag); }); } _getResolver(name) { return __awaiter(this, void 0, void 0, function* () { // Get the resolver from the blockchain const network = yield this.getNetwork(); // No ENS... if (!network.ensAddress) { logger.throwError("network does not support ENS", Logger.errors.UNSUPPORTED_OPERATION, { operation: "ENS", network: network.name }); } // keccak256("resolver(bytes32)") const transaction = { to: network.ensAddress, data: ("0x0178b8bf" + namehash(name).substring(2)) }; return this.formatter.callAddress(yield this.call(transaction)); }); } resolveName(name) { return __awaiter(this, void 0, void 0, function* () { if (name instanceof Promise) { name = yield name; } // If it is already an address, nothing to resolve try { return Promise.resolve(this.formatter.address(name)); } catch (error) { // If is is a hexstring, the address is bad (See #694) if (isHexString(name)) { throw error; } } if (typeof (name) !== "string") { logger.throwArgumentError("invalid ENS name", "name", name); } // Get the addr from the resovler const resolverAddress = yield this._getResolver(name); if (!resolverAddress) { return null; } // keccak256("addr(bytes32)") const transaction = { to: resolverAddress, data: ("0x3b3b57de" + namehash(name).substring(2)) }; return this.formatter.callAddress(yield this.call(transaction)); }); } lookupAddress(address) { return __awaiter(this, void 0, void 0, function* () { if (address instanceof Promise) { address = yield address; } address = this.formatter.address(address); const reverseName = address.substring(2).toLowerCase() + ".addr.reverse"; const resolverAddress = yield this._getResolver(reverseName); if (!resolverAddress) { return null; } // keccak("name(bytes32)") let bytes = arrayify(yield this.call({ to: resolverAddress, data: ("0x691f3431" + namehash(reverseName).substring(2)) })); // Strip off the dynamic string pointer (0x20) if (bytes.length < 32 || !BigNumber.from(bytes.slice(0, 32)).eq(32)) { return null; } bytes = bytes.slice(32); // Not a length-prefixed string if (bytes.length < 32) { return null; } // Get the length of the string (from the length-prefix) const length = BigNumber.from(bytes.slice(0, 32)).toNumber(); bytes = bytes.slice(32); // Length longer than available data if (length > bytes.length) { return null; } const name = toUtf8String(bytes.slice(0, length)); // Make sure the reverse record matches the foward record const addr = yield this.resolveName(name); if (addr != address) { return null; } return name; }); } perform(method, params) { return logger.throwError(method + " not implemented", Logger.errors.NOT_IMPLEMENTED, { operation: method }); } _startEvent(event) { this.polling = (this._events.filter((e) => e.pollable()).length > 0); } _stopEvent(event) { this.polling = (this._events.filter((e) => e.pollable()).length > 0); } _addEventListener(eventName, listener, once) { const event = new Event(getEventTag(eventName), listener, once); this._events.push(event); this._startEvent(event); return this; } on(eventName, listener) { return this._addEventListener(eventName, listener, false); } once(eventName, listener) { return this._addEventListener(eventName, listener, true); } emit(eventName, ...args) { let result = false; let stopped = []; let eventTag = getEventTag(eventName); this._events = this._events.filter((event) => { if (event.tag !== eventTag) { return true; } setTimeout(() => { event.listener.apply(this, args); }, 0); result = true; if (event.once) { stopped.push(event); return false; } return true; }); stopped.forEach((event) => { this._stopEvent(event); }); return result; } listenerCount(eventName) { if (!eventName) { return this._events.length; } let eventTag = getEventTag(eventName); return this._events.filter((event) => { return (event.tag === eventTag); }).length; } listeners(eventName) { if (eventName == null) { return this._events.map((event) => event.listener); } let eventTag = getEventTag(eventName); return this._events .filter((event) => (event.tag === eventTag)) .map((event) => event.listener); } off(eventName, listener) { if (listener == null) { return this.removeAllListeners(eventName); } const stopped = []; let found = false; let eventTag = getEventTag(eventName); this._events = this._events.filter((event) => { if (event.tag !== eventTag || event.listener != listener) { return true; } if (found) { return true; } found = true; stopped.push(event); return false; }); stopped.forEach((event) => { this._stopEvent(event); }); return this; } removeAllListeners(eventName) { let stopped = []; if (eventName == null) { stopped = this._events; this._events = []; } else { const eventTag = getEventTag(eventName); this._events = this._events.filter((event) => { if (event.tag !== eventTag) { return true; } stopped.push(event); return false; }); } stopped.forEach((event) => { this._stopEvent(event); }); return this; } }