eslint-plugin-sonarjs
Version:
SonarJS rules for ESLint
165 lines (164 loc) • 6.42 kB
JavaScript
;
/*
* SonarQube JavaScript Plugin
* Copyright (C) 2011-2025 SonarSource SA
* mailto:info AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the Sonar Source-Available License Version 1, as published by SonarSource SA.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the Sonar Source-Available License for more details.
*
* You should have received a copy of the Sonar Source-Available License
* along with this program; if not, see https://sonarsource.com/license/ssal/
*/
// https://sonarsource.github.io/rspec/#/rspec/S2259/javascript
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || (function () {
var ownKeys = function(o) {
ownKeys = Object.getOwnPropertyNames || function (o) {
var ar = [];
for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
return ar;
};
return ownKeys(o);
};
return function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
__setModuleDefault(result, mod);
return result;
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.rule = void 0;
const index_js_1 = require("../helpers/index.js");
const meta = __importStar(require("./generated-meta.js"));
var Null;
(function (Null) {
Null[Null["confirmed"] = 0] = "confirmed";
Null[Null["discarded"] = 1] = "discarded";
Null[Null["unknown"] = 2] = "unknown";
})(Null || (Null = {}));
function isNull(n) {
return (0, index_js_1.isNullLiteral)(n) || (0, index_js_1.isUndefined)(n);
}
const equalOperators = ['==', '==='];
const notEqualOperators = ['!=', '!=='];
exports.rule = {
meta: (0, index_js_1.generateMeta)(meta, {
messages: {
nullDereference: 'TypeError can be thrown as "{{symbol}}" might be null or undefined here.',
shortCircuitError: 'TypeError can be thrown as expression might be null or undefined here.',
},
}),
create(context) {
if (!(0, index_js_1.isRequiredParserServices)(context.sourceCode.parserServices)) {
return {};
}
const alreadyRaisedSymbols = new Set();
return {
MemberExpression(node) {
const { object, optional } = node;
if (!optional) {
checkNullDereference(object, context, alreadyRaisedSymbols);
}
},
'LogicalExpression MemberExpression'(node) {
const { object, optional } = node;
if (!optional) {
const ancestors = context.sourceCode.getAncestors(node);
const enclosingLogicalExpression = ancestors.find(n => n.type === 'LogicalExpression');
checkLogicalNullDereference(enclosingLogicalExpression, object, context);
}
},
ForOfStatement(node) {
const { right } = node;
checkNullDereference(right, context, alreadyRaisedSymbols);
},
'Program:exit'() {
alreadyRaisedSymbols.clear();
},
};
},
};
function getNullState(expr, node, context) {
const { left, right } = expr;
if ((isNull(right) &&
(0, index_js_1.areEquivalent)(left, node, context.sourceCode)) ||
(isNull(left) &&
(0, index_js_1.areEquivalent)(right, node, context.sourceCode))) {
if (notEqualOperators.includes(expr.operator)) {
return Null.discarded;
}
if (equalOperators.includes(expr.operator)) {
return Null.confirmed;
}
}
return Null.unknown;
}
function checkLogicalNullDereference(expr, node, context) {
if (expr.left.type === 'BinaryExpression') {
const nullState = getNullState(expr.left, node, context);
if ((nullState === Null.confirmed && expr.operator === '&&') ||
(nullState === Null.discarded && expr.operator === '||')) {
context.report({
messageId: 'shortCircuitError',
node,
});
}
}
}
function isWrittenInInnerFunction(symbol, fn) {
return symbol.references.some(ref => {
if (ref.isWrite() && ref.identifier.hasOwnProperty('parent')) {
const enclosingFn = (0, index_js_1.findFirstMatchingAncestor)(ref.identifier, node => index_js_1.functionLike.has(node.type));
return enclosingFn && enclosingFn !== fn;
}
return false;
});
}
function checkNullDereference(node, context, alreadyRaisedSymbols) {
if (node.type !== 'Identifier') {
return;
}
const scope = context.sourceCode.getScope(node);
const symbol = scope.references.find(v => v.identifier === node)?.resolved;
if (!symbol) {
return;
}
const enclosingFunction = context.sourceCode
.getAncestors(node)
.find(n => index_js_1.functionLike.has(n.type));
if (!alreadyRaisedSymbols.has(symbol) &&
!isWrittenInInnerFunction(symbol, enclosingFunction) &&
(0, index_js_1.isUndefinedOrNull)(node, context.sourceCode.parserServices)) {
alreadyRaisedSymbols.add(symbol);
context.report({
messageId: 'nullDereference',
data: {
symbol: node.name,
},
node,
});
}
}