"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 utils = require("tsutils"); var ts = require("typescript"); var Lint = require("../index"); var Rule = /** @class */ (function (_super) { tslib_1.__extends(Rule, _super); function Rule() { return _super !== null && _super.apply(this, arguments) || this; } /* tslint:enable:object-literal-sort-keys */ Rule.FAILURE_STRING = function (negate) { return "This expression is unnecessarily compared to a boolean. Just " + (negate ? "negate it" : "use it directly") + "."; }; Rule.prototype.applyWithProgram = function (sourceFile, program) { return this.applyWithFunction(sourceFile, walk, undefined, program.getTypeChecker()); }; /* tslint:disable:object-literal-sort-keys */ Rule.metadata = { ruleName: "no-boolean-literal-compare", description: "Warns on comparison to a boolean literal, as in `x === true`.", hasFix: true, optionsDescription: "Not configurable.", options: null, optionExamples: [true], rationale: Lint.Utils.dedent(templateObject_1 || (templateObject_1 = tslib_1.__makeTemplateObject(["\n Comparing boolean values to boolean literals is unnecessary, as those expressions will result in booleans too.\n Just use the boolean values directly or negate them.\n "], ["\n Comparing boolean values to boolean literals is unnecessary, as those expressions will result in booleans too.\n Just use the boolean values directly or negate them.\n "]))), type: "style", typescriptOnly: true, requiresTypeInfo: true, }; return Rule; }(Lint.Rules.TypedRule)); exports.Rule = Rule; function walk(ctx, checker) { return ts.forEachChild(ctx.sourceFile, function cb(node) { if (utils.isBinaryExpression(node)) { var cmp = getBooleanComparison(node, checker); if (cmp !== undefined) { ctx.addFailureAtNode(cmp.expression, Rule.FAILURE_STRING(cmp.negate), fix(node, cmp)); } } return ts.forEachChild(node, cb); }); } function getBooleanComparison(node, checker) { var cmp = deconstructComparison(node); return cmp === undefined || !utils.isTypeFlagSet(checker.getTypeAtLocation(cmp.expression), ts.TypeFlags.Boolean) ? undefined : cmp; } function fix(node, _a) { var negate = _a.negate, expression = _a.expression; var deleted = node.left === expression ? Lint.Replacement.deleteFromTo(node.left.end, node.end) : Lint.Replacement.deleteFromTo(node.getStart(), node.right.getStart()); if (!negate) { return deleted; } else if (needsParenthesesForNegate(expression)) { return [ deleted, Lint.Replacement.appendText(node.getStart(), "!("), Lint.Replacement.appendText(node.getEnd(), ")"), ]; } else { return [ deleted, Lint.Replacement.appendText(node.getStart(), "!"), ]; } } function needsParenthesesForNegate(node) { switch (node.kind) { case ts.SyntaxKind.AsExpression: case ts.SyntaxKind.BinaryExpression: return true; default: return false; } } function deconstructComparison(node) { var left = node.left, operatorToken = node.operatorToken, right = node.right; var eq = Lint.getEqualsKind(operatorToken); if (eq === undefined) { return undefined; } var leftValue = booleanFromExpression(left); if (leftValue !== undefined) { return { negate: leftValue !== eq.isPositive, expression: right }; } var rightValue = booleanFromExpression(right); if (rightValue !== undefined) { return { negate: rightValue !== eq.isPositive, expression: left }; } return undefined; } function booleanFromExpression(node) { switch (node.kind) { case ts.SyntaxKind.TrueKeyword: return true; case ts.SyntaxKind.FalseKeyword: return false; default: return undefined; } } var templateObject_1;