libreccm-legacy/trunk-images/node_modules/tslint/lib/rules/noUnnecessaryInitializerRul...

131 lines
5.0 KiB
JavaScript

/**
* @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.
*/
"use strict";
var __extends = (this && this.__extends) || (function () {
var extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
var utils = require("tsutils");
var ts = require("typescript");
var Lint = require("../index");
var Rule = (function (_super) {
__extends(Rule, _super);
function Rule() {
return _super !== null && _super.apply(this, arguments) || this;
}
Rule.prototype.apply = function (sourceFile) {
return this.applyWithWalker(new Walker(sourceFile, this.getOptions()));
};
return Rule;
}(Lint.Rules.AbstractRule));
/* tslint:disable:object-literal-sort-keys */
Rule.metadata = {
ruleName: "no-unnecessary-initializer",
description: "Forbids a 'var'/'let' statement or destructuring initializer to be initialized to 'undefined'.",
hasFix: true,
optionsDescription: "Not configurable.",
options: null,
optionExamples: ["true"],
type: "style",
typescriptOnly: false,
};
/* tslint:enable:object-literal-sort-keys */
Rule.FAILURE_STRING = "Unnecessary initialization to 'undefined'.";
Rule.FAILURE_STRING_PARAMETER = "Use an optional parameter instead of initializing to 'undefined'. " +
"Also, the type declaration does not need to include '| undefined'.";
exports.Rule = Rule;
var Walker = (function (_super) {
__extends(Walker, _super);
function Walker() {
return _super !== null && _super.apply(this, arguments) || this;
}
Walker.prototype.visitVariableDeclaration = function (node) {
if (utils.isBindingPattern(node.name)) {
for (var _i = 0, _a = node.name.elements; _i < _a.length; _i++) {
var elem = _a[_i];
if (elem.kind === ts.SyntaxKind.BindingElement) {
this.checkInitializer(elem);
}
}
}
else if (!Lint.isNodeFlagSet(node.parent, ts.NodeFlags.Const)) {
this.checkInitializer(node);
}
_super.prototype.visitVariableDeclaration.call(this, node);
};
Walker.prototype.visitMethodDeclaration = function (node) {
this.checkSignature(node);
_super.prototype.visitMethodDeclaration.call(this, node);
};
Walker.prototype.visitFunctionDeclaration = function (node) {
this.checkSignature(node);
_super.prototype.visitFunctionDeclaration.call(this, node);
};
Walker.prototype.visitConstructorDeclaration = function (node) {
this.checkSignature(node);
_super.prototype.visitConstructorDeclaration.call(this, node);
};
Walker.prototype.checkSignature = function (_a) {
var _this = this;
var parameters = _a.parameters;
parameters.forEach(function (parameter, i) {
if (isUndefined(parameter.initializer)) {
if (parametersAllOptionalAfter(parameters, i)) {
// No fix since they may want to remove '| undefined' from the type.
_this.addFailureAtNode(parameter, Rule.FAILURE_STRING_PARAMETER);
}
else {
_this.failWithFix(parameter);
}
}
});
};
Walker.prototype.checkInitializer = function (node) {
if (isUndefined(node.initializer)) {
this.failWithFix(node);
}
};
Walker.prototype.failWithFix = function (node) {
var fix = this.createFix(this.deleteFromTo(Lint.childOfKind(node, ts.SyntaxKind.EqualsToken).pos, node.end));
this.addFailureAtNode(node, Rule.FAILURE_STRING, fix);
};
return Walker;
}(Lint.RuleWalker));
function parametersAllOptionalAfter(parameters, idx) {
for (var i = idx + 1; i < parameters.length; i++) {
if (parameters[i].questionToken) {
return true;
}
if (!parameters[i].initializer) {
return false;
}
}
return true;
}
function isUndefined(node) {
return node !== undefined &&
node.kind === ts.SyntaxKind.Identifier &&
node.originalKeywordKind === ts.SyntaxKind.UndefinedKeyword;
}