4 * Copyright 2018 Palantir Technologies, Inc.
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
18 Object.defineProperty(exports, "__esModule", { value: true });
19 var tslib_1 = require("tslib");
20 var tsutils_1 = require("tsutils");
21 var ts = require("typescript");
22 var Lint = require("../index");
23 var Rule = /** @class */ (function (_super) {
24 tslib_1.__extends(Rule, _super);
26 return _super !== null && _super.apply(this, arguments) || this;
28 Rule.prototype.applyWithProgram = function (sourceFile, program) {
29 return this.applyWithFunction(sourceFile, walk, undefined, program.getTypeChecker());
31 /* tslint:disable:object-literal-sort-keys */
33 ruleName: "restrict-plus-operands",
34 description: "When adding two variables, operands must both be of type number or of type string.",
35 optionsDescription: "Not configurable.",
37 optionExamples: [true],
38 type: "functionality",
39 typescriptOnly: false,
40 requiresTypeInfo: true,
42 /* tslint:enable:object-literal-sort-keys */
43 Rule.INVALID_TYPES_ERROR = "Operands of '+' operation must either be both strings or both numbers or both bigints";
44 Rule.SUGGEST_TEMPLATE_LITERALS = ". Consider using template literals.";
46 }(Lint.Rules.TypedRule));
48 function walk(ctx, tc) {
49 return ts.forEachChild(ctx.sourceFile, function cb(node) {
50 if (tsutils_1.isBinaryExpression(node) && node.operatorToken.kind === ts.SyntaxKind.PlusToken) {
51 var leftType = tc.getTypeAtLocation(node.left);
52 var leftTypeStr = getBaseTypeOfLiteralType(leftType);
53 var rightType = tc.getTypeAtLocation(node.right);
54 var rightTypeStr = getBaseTypeOfLiteralType(rightType);
55 if (leftTypeStr === "invalid" ||
56 rightTypeStr === "invalid" ||
57 leftTypeStr !== rightTypeStr) {
58 var actualTypes = ", but found " + getTypeString(tc, node.left, leftType) + " + " + getTypeString(tc, node.right, rightType);
59 var message = Rule.INVALID_TYPES_ERROR + actualTypes;
60 if (leftTypeStr === "string" || rightTypeStr === "string") {
61 message += Rule.SUGGEST_TEMPLATE_LITERALS;
63 return ctx.addFailureAtNode(node, message);
66 return ts.forEachChild(node, cb);
69 function getTypeString(tc, node, type) {
70 var typeString = tc.typeToString(type, node);
71 if (typeString === "undefined[]" &&
72 ts.isArrayLiteralExpression(node) &&
73 node.elements.length === 0) {
74 // Special case literal "[]" arrays that would otherwise be emitted as undefined[].
79 function getBaseTypeOfLiteralType(type) {
80 if (tsutils_1.isTypeFlagSet(type, ts.TypeFlags.StringLiteral) ||
81 tsutils_1.isTypeFlagSet(type, ts.TypeFlags.String)) {
84 else if (tsutils_1.isTypeFlagSet(type, ts.TypeFlags.NumberLiteral) ||
85 tsutils_1.isTypeFlagSet(type, ts.TypeFlags.Number)) {
88 else if (tsutils_1.isTypeFlagSet(type, ts.TypeFlags.BigIntLiteral) ||
89 tsutils_1.isTypeFlagSet(type, ts.TypeFlags.BigInt)) {
92 else if (tsutils_1.isUnionType(type) && !tsutils_1.isTypeFlagSet(type, ts.TypeFlags.Enum)) {
93 var types = type.types.map(getBaseTypeOfLiteralType);
94 return allSame(types) ? types[0] : "invalid";
96 else if (tsutils_1.isTypeFlagSet(type, ts.TypeFlags.EnumLiteral)) {
97 // Compatibility for TypeScript pre-2.4, which used EnumLiteralType instead of LiteralType
98 getBaseTypeOfLiteralType(type.baseType);
102 function allSame(array) {
103 return array.every(function (value) { return value === array[0]; });