eslint-plugin-sonarjs
Version:
SonarJS rules for ESLint
153 lines (152 loc) • 6.55 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/S4143
Object.defineProperty(exports, "__esModule", { value: true });
exports.rule = void 0;
const index_js_1 = require("../helpers/index.js");
const meta_js_1 = require("./meta.js");
const message = 'Verify this is the index that was intended; "{{index}}" was already set on line {{line}}.';
exports.rule = {
meta: (0, index_js_1.generateMeta)(meta_js_1.meta, {
messages: {
verifyIntendedIndex: message,
},
}, true),
create(context) {
return {
SwitchCase(node) {
checkStatements(node.consequent);
},
BlockStatement(node) {
checkStatements(node.body);
},
Program(node) {
checkStatements((0, index_js_1.getProgramStatements)(node));
},
};
function checkStatements(statements) {
const usedKeys = new Map();
let collection;
statements.forEach(statement => {
const keyWriteUsage = getKeyWriteUsage(statement);
if (keyWriteUsage) {
if (collection &&
!(0, index_js_1.areEquivalent)(keyWriteUsage.collectionNode, collection, context.sourceCode)) {
usedKeys.clear();
}
const sameKeyWriteUsage = usedKeys.get(keyWriteUsage.indexOrKey);
if (sameKeyWriteUsage?.node.loc) {
const secondaryLocations = [
(0, index_js_1.toSecondaryLocation)(sameKeyWriteUsage.node, 'Original value'),
];
(0, index_js_1.report)(context, {
node: keyWriteUsage.node,
messageId: 'verifyIntendedIndex',
message,
data: {
index: keyWriteUsage.indexOrKey,
line: sameKeyWriteUsage.node.loc.start.line,
},
}, secondaryLocations);
}
usedKeys.set(keyWriteUsage.indexOrKey, keyWriteUsage);
collection = keyWriteUsage.collectionNode;
}
else {
usedKeys.clear();
}
});
}
function getKeyWriteUsage(node) {
if (node.type === 'ExpressionStatement') {
return arrayKeyWriteUsage(node.expression) || mapOrSetKeyWriteUsage(node.expression);
}
return undefined;
}
function arrayKeyWriteUsage(node) {
// a[b] = ...
if (isSimpleAssignment(node) && node.left.type === 'MemberExpression' && node.left.computed) {
const { left, right } = node;
const index = extractIndex(left.property);
if (index !== undefined && !isUsed(left.object, right)) {
return {
collectionNode: left.object,
indexOrKey: index,
node,
};
}
}
return undefined;
}
function mapOrSetKeyWriteUsage(node) {
if (node.type === 'CallExpression' && node.callee.type === 'MemberExpression') {
const propertyAccess = node.callee;
if ((0, index_js_1.isIdentifier)(propertyAccess.property)) {
const methodName = propertyAccess.property.name;
const addMethod = methodName === 'add' && node.arguments.length === 1;
const setMethod = methodName === 'set' && node.arguments.length === 2;
if (addMethod || setMethod) {
const key = extractIndex(node.arguments[0]);
if (key) {
return {
collectionNode: propertyAccess.object,
indexOrKey: key,
node,
};
}
}
}
}
return undefined;
}
function extractIndex(node) {
if ((0, index_js_1.isLiteral)(node)) {
const { value } = node;
return typeof value === 'number' || typeof value === 'string' ? String(value) : undefined;
}
else if ((0, index_js_1.isIdentifier)(node)) {
return node.name;
}
return undefined;
}
function isUsed(value, expression) {
const valueTokens = context.sourceCode.getTokens(value);
const expressionTokens = context.sourceCode.getTokens(expression);
const foundUsage = expressionTokens.find((token, index) => {
if (eq(token, valueTokens[0])) {
for (let expressionIndex = index, valueIndex = 0; expressionIndex < expressionTokens.length && valueIndex < valueTokens.length; expressionIndex++, valueIndex++) {
if (!eq(expressionTokens[expressionIndex], valueTokens[valueIndex])) {
break;
}
else if (valueIndex === valueTokens.length - 1) {
return true;
}
}
}
return false;
});
return foundUsage !== undefined;
}
},
};
function eq(token1, token2) {
return token1.value === token2.value;
}
function isSimpleAssignment(node) {
return node.type === 'AssignmentExpression' && node.operator === '=';
}