/** * @license * Copyright 2013 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 NoSwitchCaseFallThroughWalker(sourceFile, this.ruleName, undefined)); }; return Rule; }(Lint.Rules.AbstractRule)); /* tslint:disable:object-literal-sort-keys */ Rule.metadata = { ruleName: "no-switch-case-fall-through", description: "Disallows falling through case statements.", descriptionDetails: (_a = ["\n For example, the following is not allowed:\n\n ```ts\n switch(foo) {\n case 1:\n someFunc(foo);\n case 2:\n someOtherFunc(foo);\n }\n ```\n\n However, fall through is allowed when case statements are consecutive or\n a magic `/* falls through */` comment is present. The following is valid:\n\n ```ts\n switch(foo) {\n case 1:\n someFunc(foo);\n /* falls through */\n case 2:\n case 3:\n someOtherFunc(foo);\n }\n ```"], _a.raw = ["\n For example, the following is not allowed:\n\n \\`\\`\\`ts\n switch(foo) {\n case 1:\n someFunc(foo);\n case 2:\n someOtherFunc(foo);\n }\n \\`\\`\\`\n\n However, fall through is allowed when case statements are consecutive or\n a magic \\`/* falls through */\\` comment is present. The following is valid:\n\n \\`\\`\\`ts\n switch(foo) {\n case 1:\n someFunc(foo);\n /* falls through */\n case 2:\n case 3:\n someOtherFunc(foo);\n }\n \\`\\`\\`"], Lint.Utils.dedent(_a)), rationale: "Fall though in switch statements is often unintentional and a bug.", optionsDescription: "Not configurable.", options: null, optionExamples: ["true"], type: "functionality", typescriptOnly: false, }; /* tslint:enable:object-literal-sort-keys */ Rule.FAILURE_STRING_PART = "expected a 'break' before "; exports.Rule = Rule; var NoSwitchCaseFallThroughWalker = (function (_super) { __extends(NoSwitchCaseFallThroughWalker, _super); function NoSwitchCaseFallThroughWalker() { return _super !== null && _super.apply(this, arguments) || this; } NoSwitchCaseFallThroughWalker.prototype.walk = function (sourceFile) { var _this = this; var cb = function (node) { if (node.kind === ts.SyntaxKind.SwitchStatement) { _this.visitSwitchStatement(node); } return ts.forEachChild(node, cb); }; return ts.forEachChild(sourceFile, cb); }; NoSwitchCaseFallThroughWalker.prototype.visitSwitchStatement = function (node) { var clauses = node.caseBlock.clauses; var len = clauses.length - 1; // last clause doesn't need to be checked for (var i = 0; i < len; ++i) { if (clauses[i].statements.length !== 0 && // TODO type assertion can be removed with typescript 2.2 !utils.endsControlFlow(clauses[i]) && !this.isFallThroughAllowed(clauses[i])) { this.reportError(clauses[i + 1]); } } }; NoSwitchCaseFallThroughWalker.prototype.isFallThroughAllowed = function (clause) { var sourceFileText = this.sourceFile.text; var comments = ts.getLeadingCommentRanges(sourceFileText, clause.end); if (comments === undefined) { return false; } for (var _i = 0, comments_1 = comments; _i < comments_1.length; _i++) { var comment = comments_1[_i]; var commentText = void 0; if (comment.kind === ts.SyntaxKind.MultiLineCommentTrivia) { commentText = sourceFileText.substring(comment.pos + 2, comment.end - 2); } else { commentText = sourceFileText.substring(comment.pos + 2, comment.end); } if (commentText.trim() === "falls through") { return true; } } return false; }; NoSwitchCaseFallThroughWalker.prototype.reportError = function (clause) { var keyword = clause.kind === ts.SyntaxKind.CaseClause ? "case" : "default"; this.addFailureAt(clause.getStart(this.sourceFile), keyword.length, Rule.FAILURE_STRING_PART + "'" + keyword + "'"); }; return NoSwitchCaseFallThroughWalker; }(Lint.AbstractWalker)); exports.NoSwitchCaseFallThroughWalker = NoSwitchCaseFallThroughWalker; var _a;