"use strict"; /** * @license * Copyright 2017 Palantir Technologies, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ Object.defineProperty(exports, "__esModule", { value: true }); var tslib_1 = require("tslib"); var _a, _b; var utils = require("tsutils"); var ts = require("typescript"); var Lint = require("../index"); var ALLOW_THIS_DESTRUCTURING = "allow-destructuring"; var ALLOWED_THIS_NAMES = "allowed-names"; var parseConfigOptions = function (configOptions) { var allowedNames = []; var allowDestructuring = false; if (configOptions !== undefined) { allowDestructuring = !!configOptions[ALLOW_THIS_DESTRUCTURING]; if (configOptions[ALLOWED_THIS_NAMES] !== undefined) { allowedNames.push.apply(allowedNames, configOptions[ALLOWED_THIS_NAMES]); } } return { allowedNames: allowedNames, allowDestructuring: allowDestructuring }; }; var Rule = /** @class */ (function (_super) { tslib_1.__extends(Rule, _super); function Rule() { return _super !== null && _super.apply(this, arguments) || this; } Rule.FAILURE_STRING_FACTORY_IDENTIFIERS = function (name) { return "Assigning `this` reference to local variable not allowed: " + name + "."; }; Rule.prototype.apply = function (sourceFile) { var options = parseConfigOptions(this.ruleArguments[0]); var noThisAssignmentWalker = new NoThisAssignmentWalker(sourceFile, this.ruleName, options); return this.applyWithWalker(noThisAssignmentWalker); }; Rule.metadata = { description: "Disallows unnecessary references to `this`.", optionExamples: [ true, [ true, (_a = {}, _a[ALLOWED_THIS_NAMES] = ["^self$"], _a[ALLOW_THIS_DESTRUCTURING] = true, _a), ], ], options: { additionalProperties: false, properties: (_b = {}, _b[ALLOW_THIS_DESTRUCTURING] = { type: "boolean", }, _b[ALLOWED_THIS_NAMES] = { listType: "string", type: "list", }, _b), type: "object", }, optionsDescription: Lint.Utils.dedent(templateObject_1 || (templateObject_1 = tslib_1.__makeTemplateObject(["\n Two options may be provided on an object:\n\n * `", "` allows using destructuring to access members of `this` (e.g. `{ foo, bar } = this;`).\n * `", "` may be specified as a list of regular expressions to match allowed variable names."], ["\n Two options may be provided on an object:\n\n * \\`", "\\` allows using destructuring to access members of \\`this\\` (e.g. \\`{ foo, bar } = this;\\`).\n * \\`", "\\` may be specified as a list of regular expressions to match allowed variable names."])), ALLOW_THIS_DESTRUCTURING, ALLOWED_THIS_NAMES), rationale: Lint.Utils.dedent(templateObject_2 || (templateObject_2 = tslib_1.__makeTemplateObject(["\n Assigning a variable to `this` instead of properly using arrow lambdas may be a symptom of pre-ES6 practices\n or not managing scope well.\n\n Instead of storing a reference to `this` and using it inside a `function () {`:\n\n ```\n const self = this;\n\n setTimeout(function () {\n self.doWork();\n });\n ```\n\n Use `() =>` arrow lambdas, as they preserve `this` scope for you:\n\n ```\n setTimeout(() => {\n this.doWork();\n });\n ```\n "], ["\n Assigning a variable to \\`this\\` instead of properly using arrow lambdas may be a symptom of pre-ES6 practices\n or not managing scope well.\n\n Instead of storing a reference to \\`this\\` and using it inside a \\`function () {\\`:\n\n \\`\\`\\`\n const self = this;\n\n setTimeout(function () {\n self.doWork();\n });\n \\`\\`\\`\n\n Use \\`() =>\\` arrow lambdas, as they preserve \\`this\\` scope for you:\n\n \\`\\`\\`\n setTimeout(() => {\n this.doWork();\n });\n \\`\\`\\`\n "]))), ruleName: "no-this-assignment", type: "functionality", typescriptOnly: false, }; Rule.FAILURE_STRING_BINDINGS = "Don't assign members of `this` to local variables."; return Rule; }(Lint.Rules.AbstractRule)); exports.Rule = Rule; var NoThisAssignmentWalker = /** @class */ (function (_super) { tslib_1.__extends(NoThisAssignmentWalker, _super); function NoThisAssignmentWalker() { var _this = _super !== null && _super.apply(this, arguments) || this; _this.allowedThisNameTesters = _this.options.allowedNames.map(function (allowedThisName) { return new RegExp(allowedThisName); }); _this.visitNode = function (node) { if (utils.isVariableDeclaration(node)) { _this.visitVariableDeclaration(node); } ts.forEachChild(node, _this.visitNode); }; return _this; } NoThisAssignmentWalker.prototype.walk = function (sourceFile) { ts.forEachChild(sourceFile, this.visitNode); }; NoThisAssignmentWalker.prototype.visitVariableDeclaration = function (node) { if (node.initializer === undefined || node.initializer.kind !== ts.SyntaxKind.ThisKeyword) { return; } switch (node.name.kind) { case ts.SyntaxKind.Identifier: if (this.variableNameIsBanned(node.name.text)) { this.addFailureAtNode(node, Rule.FAILURE_STRING_FACTORY_IDENTIFIERS(node.name.text)); } break; default: if (!this.options.allowDestructuring) { this.addFailureAtNode(node, Rule.FAILURE_STRING_BINDINGS); } } }; NoThisAssignmentWalker.prototype.variableNameIsBanned = function (name) { for (var _i = 0, _a = this.allowedThisNameTesters; _i < _a.length; _i++) { var tester = _a[_i]; if (tester.test(name)) { return false; } } return true; }; return NoThisAssignmentWalker; }(Lint.AbstractWalker)); var templateObject_1, templateObject_2;