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Diffstat (limited to 'node_modules/tslint/lib/rules/onlyArrowFunctionsRule.js')
-rw-r--r-- | node_modules/tslint/lib/rules/onlyArrowFunctionsRule.js | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/node_modules/tslint/lib/rules/onlyArrowFunctionsRule.js b/node_modules/tslint/lib/rules/onlyArrowFunctionsRule.js new file mode 100644 index 000000000..f5d8187f8 --- /dev/null +++ b/node_modules/tslint/lib/rules/onlyArrowFunctionsRule.js @@ -0,0 +1,97 @@ +"use strict"; +/** + * @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. + */ +Object.defineProperty(exports, "__esModule", { value: true }); +var tslib_1 = require("tslib"); +var utils = require("tsutils"); +var ts = require("typescript"); +var Lint = require("../index"); +var OPTION_ALLOW_DECLARATIONS = "allow-declarations"; +var OPTION_ALLOW_NAMED_FUNCTIONS = "allow-named-functions"; +var Rule = (function (_super) { + tslib_1.__extends(Rule, _super); + function Rule() { + return _super !== null && _super.apply(this, arguments) || this; + } + Rule.prototype.apply = function (sourceFile) { + return this.applyWithFunction(sourceFile, walk, parseOptions(this.ruleArguments)); + }; + return Rule; +}(Lint.Rules.AbstractRule)); +/* tslint:disable:object-literal-sort-keys */ +Rule.metadata = { + ruleName: "only-arrow-functions", + description: "Disallows traditional (non-arrow) function expressions.", + rationale: "Traditional functions don't bind lexical scope, which can lead to unexpected behavior when accessing 'this'.", + optionsDescription: (_a = ["\n Two arguments may be optionally provided:\n\n * `\"", "\"` allows standalone function declarations.\n * `\"", "\"` allows the expression `function foo() {}` but not `function() {}`.\n "], _a.raw = ["\n Two arguments may be optionally provided:\n\n * \\`\"", "\"\\` allows standalone function declarations.\n * \\`\"", "\"\\` allows the expression \\`function foo() {}\\` but not \\`function() {}\\`.\n "], Lint.Utils.dedent(_a, OPTION_ALLOW_DECLARATIONS, OPTION_ALLOW_NAMED_FUNCTIONS)), + options: { + type: "array", + items: { + type: "string", + enum: [OPTION_ALLOW_DECLARATIONS, OPTION_ALLOW_NAMED_FUNCTIONS], + }, + minLength: 0, + maxLength: 1, + }, + optionExamples: [true, [true, OPTION_ALLOW_DECLARATIONS, OPTION_ALLOW_NAMED_FUNCTIONS]], + type: "typescript", + typescriptOnly: false, +}; +/* tslint:enable:object-literal-sort-keys */ +Rule.FAILURE_STRING = "non-arrow functions are forbidden"; +exports.Rule = Rule; +function parseOptions(ruleArguments) { + return { + allowDeclarations: hasOption(OPTION_ALLOW_DECLARATIONS), + allowNamedFunctions: hasOption(OPTION_ALLOW_NAMED_FUNCTIONS), + }; + function hasOption(name) { + return ruleArguments.indexOf(name) !== -1; + } +} +function walk(ctx) { + var sourceFile = ctx.sourceFile, _a = ctx.options, allowDeclarations = _a.allowDeclarations, allowNamedFunctions = _a.allowNamedFunctions; + return ts.forEachChild(sourceFile, function cb(node) { + switch (node.kind) { + case ts.SyntaxKind.FunctionDeclaration: + if (allowDeclarations) { + break; + } + // falls through + case ts.SyntaxKind.FunctionExpression: { + var f = node; + if (!(allowNamedFunctions && f.name !== undefined) && !functionIsExempt(f)) { + ctx.addFailureAtNode(Lint.childOfKind(node, ts.SyntaxKind.FunctionKeyword), Rule.FAILURE_STRING); + } + } + } + return ts.forEachChild(node, cb); + }); +} +/** Generator functions and functions using `this` are allowed. */ +function functionIsExempt(node) { + return node.asteriskToken !== undefined || hasThisParameter(node) || node.body !== undefined && usesThisInBody(node.body); +} +function hasThisParameter(node) { + var first = node.parameters[0]; + return first !== undefined && first.name.kind === ts.SyntaxKind.Identifier && + first.name.originalKeywordKind === ts.SyntaxKind.ThisKeyword; +} +function usesThisInBody(node) { + return node.kind === ts.SyntaxKind.ThisKeyword || !utils.hasOwnThisReference(node) && ts.forEachChild(node, usesThisInBody); +} +var _a; |