diff options
author | Florian Dold <florian.dold@gmail.com> | 2017-05-28 00:38:50 +0200 |
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committer | Florian Dold <florian.dold@gmail.com> | 2017-05-28 00:40:43 +0200 |
commit | 7fff4499fd915bcea3fa93b1aa8b35f4fe7a6027 (patch) | |
tree | 6de9a1aebd150a23b7f8c273ec657a5d0a18fe3e /node_modules/tslint/lib/rules/preferObjectSpreadRule.js | |
parent | 963b7a41feb29cc4be090a2446bdfe0c1f1bcd81 (diff) |
add linting (and some initial fixes)
Diffstat (limited to 'node_modules/tslint/lib/rules/preferObjectSpreadRule.js')
-rw-r--r-- | node_modules/tslint/lib/rules/preferObjectSpreadRule.js | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/node_modules/tslint/lib/rules/preferObjectSpreadRule.js b/node_modules/tslint/lib/rules/preferObjectSpreadRule.js new file mode 100644 index 000000000..f08a648ca --- /dev/null +++ b/node_modules/tslint/lib/rules/preferObjectSpreadRule.js @@ -0,0 +1,116 @@ +"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 tsutils_1 = require("tsutils"); +var ts = require("typescript"); +var Lint = require("../index"); +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); + }; + return Rule; +}(Lint.Rules.AbstractRule)); +/* tslint:disable:object-literal-sort-keys */ +Rule.metadata = { + ruleName: "prefer-object-spread", + description: "Enforces the use of the ES2015 object spread operator over `Object.assign()` where appropriate.", + rationale: "Object spread allows for better type checking and inference.", + optionsDescription: "Not configurable.", + options: null, + optionExamples: [true], + type: "functionality", + typescriptOnly: false, + hasFix: true, +}; +/* tslint:enable:object-literal-sort-keys */ +Rule.FAILURE_STRING = "Use the object spread operator instead."; +Rule.ASSIGNMENT_FAILURE_STRING = "'Object.assign' returns the first argument. Prefer object spread if you want a new object."; +exports.Rule = Rule; +function walk(ctx) { + return ts.forEachChild(ctx.sourceFile, function cb(node) { + if (tsutils_1.isCallExpression(node) && node.arguments.length !== 0 && + tsutils_1.isPropertyAccessExpression(node.expression) && node.expression.name.text === "assign" && + tsutils_1.isIdentifier(node.expression.expression) && node.expression.expression.text === "Object" && + // Object.assign(...someArray) cannot be written as object spread + !node.arguments.some(tsutils_1.isSpreadElement)) { + if (node.arguments[0].kind === ts.SyntaxKind.ObjectLiteralExpression) { + ctx.addFailureAtNode(node, Rule.FAILURE_STRING, createFix(node, ctx.sourceFile)); + } + else { + var parent = node.parent; + if (parent.kind === ts.SyntaxKind.VariableDeclaration || + tsutils_1.isBinaryExpression(parent) && parent.operatorToken.kind === ts.SyntaxKind.EqualsToken) { + ctx.addFailureAtNode(node, Rule.ASSIGNMENT_FAILURE_STRING, createFix(node, ctx.sourceFile)); + } + } + } + return ts.forEachChild(node, cb); + }); +} +function createFix(node, sourceFile) { + var args = node.arguments; + var fix = [ + Lint.Replacement.replaceFromTo(node.getStart(sourceFile), args[0].getStart(sourceFile), "{"), + new Lint.Replacement(node.end - 1, 1, "}"), + ]; + for (var i = 0; i < args.length; ++i) { + var arg = args[i]; + if (tsutils_1.isObjectLiteralExpression(arg)) { + if (arg.properties.length === 0) { + var end = arg.end; + if (i !== args.length - 1) { + end = args[i + 1].getStart(sourceFile); + } + else if (args.hasTrailingComma === true) { + end = args.end; + } + // remove empty object iteral and the following comma if exists + fix.push(Lint.Replacement.deleteFromTo(arg.getStart(sourceFile), end)); + } + else { + fix.push( + // remove open brace + Lint.Replacement.deleteText(arg.getStart(sourceFile), 1), + // remove trailing comma if exists and close brace + Lint.Replacement.deleteFromTo(arg.properties[arg.properties.length - 1].end, arg.end)); + } + } + else { + var parens = needsParens(arg); + fix.push(Lint.Replacement.appendText(arg.getStart(sourceFile), parens ? "...(" : "...")); + if (parens) { + fix.push(Lint.Replacement.appendText(arg.end, ")")); + } + } + } + return fix; +} +function needsParens(node) { + switch (node.kind) { + case ts.SyntaxKind.ConditionalExpression: + case ts.SyntaxKind.BinaryExpression: + return true; + default: + return false; + } +} |