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/* Any copyright is dedicated to the Public Domain.
"use strict";
// ------------------------------------------------------------------------------
// Requirements
// ------------------------------------------------------------------------------
var rule = require("../lib/rules/no-useless-removeEventListener");
var RuleTester = require("eslint").RuleTester;
const ruleTester = new RuleTester({ parserOptions: { ecmaVersion: "latest" } });
// ------------------------------------------------------------------------------
// Tests
// ------------------------------------------------------------------------------
function invalidCode(code) {
return { code, errors: [{ messageId: "useOnce", type: "CallExpression" }] };
}
ruleTester.run("no-useless-removeEventListener", rule, {
valid: [
// Listeners that aren't a function are always valid.
"elt.addEventListener('click', handler);",
"elt.addEventListener('click', handler, true);",
"elt.addEventListener('click', handler, {once: true});",
// Should not fail on empty functions.
"elt.addEventListener('click', function() {});",
// Should not reject when removing a listener for another event.
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener('keypress', listener);" +
"});",
// Should not reject when there's another instruction before
// removeEventListener.
"elt.addEventListener('click', function listener() {" +
" elt.focus();" +
" elt.removeEventListener('click', listener);" +
"});",
// Should not reject when wantsUntrusted is true.
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener('click', listener);" +
"}, false, true);",
// Should not reject when there's a literal and a variable
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener(eventName, listener);" +
"});",
// Should not reject when there's 2 different variables
"elt.addEventListener(event1, function listener() {" +
" elt.removeEventListener(event2, listener);" +
"});",
// Should not fail if this is a different type of event listener function.
"myfunc.addEventListener(listener);",
],
invalid: [
invalidCode(
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener('click', listener);" +
"});"
),
invalidCode(
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener('click', listener, true);" +
"}, true);"
),
invalidCode(
"elt.addEventListener('click', function listener() {" +
" elt.removeEventListener('click', listener);" +
"}, {once: true});"
),
invalidCode(
"elt.addEventListener('click', function listener() {" +
" /* Comment */" +
" elt.removeEventListener('click', listener);" +
"});"
),
invalidCode(
"elt.addEventListener('click', function() {" +
" elt.removeEventListener('click', arguments.callee);" +
"});"
),
invalidCode(
"elt.addEventListener(eventName, function listener() {" +
" elt.removeEventListener(eventName, listener);" +
"});"
),
],
});