eslint-plugin-sonarjs
Version:
SonarJS rules for ESLint
256 lines (255 loc) • 7.01 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/S2201
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 METHODS_WITHOUT_SIDE_EFFECTS = {
array: new Set([
'concat',
'includes',
'join',
'slice',
'indexOf',
'lastIndexOf',
'entries',
'filter',
'findIndex',
'keys',
'map',
'values',
'find',
'reduce',
'reduceRight',
'toString',
'toLocaleString',
]),
date: new Set([
'getDate',
'getDay',
'getFullYear',
'getHours',
'getMilliseconds',
'getMinutes',
'getMonth',
'getSeconds',
'getTime',
'getTimezoneOffset',
'getUTCDate',
'getUTCDay',
'getUTCFullYear',
'getUTCHours',
'getUTCMilliseconds',
'getUTCMinutes',
'getUTCMonth',
'getUTCSeconds',
'getYear',
'toDateString',
'toISOString',
'toJSON',
'toGMTString',
'toLocaleDateString',
'toLocaleTimeString',
'toTimeString',
'toUTCString',
'toString',
'toLocaleString',
]),
math: new Set([
'abs',
'E',
'LN2',
'LN10',
'LOG2E',
'LOG10E',
'PI',
'SQRT1_2',
'SQRT2',
'abs',
'acos',
'acosh',
'asin',
'asinh',
'atan',
'atanh',
'atan2',
'cbrt',
'ceil',
'clz32',
'cos',
'cosh',
'exp',
'expm1',
'floor',
'fround',
'hypot',
'imul',
'log',
'log1p',
'log10',
'log2',
'max',
'min',
'pow',
'random',
'round',
'sign',
'sin',
'sinh',
'sqrt',
'tan',
'tanh',
'trunc',
]),
number: new Set(['toExponential', 'toFixed', 'toPrecision', 'toLocaleString', 'toString']),
regexp: new Set(['test', 'toString']),
string: new Set([
'charAt',
'charCodeAt',
'codePointAt',
'concat',
'includes',
'endsWith',
'indexOf',
'lastIndexOf',
'localeCompare',
'match',
'normalize',
'padEnd',
'padStart',
'repeat',
'replace',
'search',
'slice',
'split',
'startsWith',
'substr',
'substring',
'toLocaleLowerCase',
'toLocaleUpperCase',
'toLowerCase',
'toUpperCase',
'trim',
'length',
'toString',
'valueOf',
// HTML wrapper methods
'anchor',
'big',
'blink',
'bold',
'fixed',
'fontcolor',
'fontsize',
'italics',
'link',
'small',
'strike',
'sub',
'sup',
]),
};
exports.rule = {
meta: (0, index_js_1.generateMeta)(meta_js_1.meta, {
messages: {
useForEach: `Consider using "forEach" instead of "map" as its return value is not being used here.`,
returnValueMustBeUsed: 'The return value of "{{methodName}}" must be used.',
},
}),
create(context) {
const services = context.sourceCode.parserServices;
if (!(0, index_js_1.isRequiredParserServices)(services)) {
return {};
}
return {
CallExpression: (node) => {
const call = node;
const { callee } = call;
if (callee.type === 'MemberExpression') {
const { parent } = node;
if (parent && parent.type === 'ExpressionStatement') {
const methodName = context.sourceCode.getText(callee.property);
const objectType = services.program
.getTypeChecker()
.getTypeAtLocation(services.esTreeNodeToTSNodeMap.get(callee.object));
if (!hasSideEffect(methodName, objectType, services) &&
!isReplaceWithCallback(methodName, call.arguments, services)) {
context.report(reportDescriptor(methodName, node));
}
}
}
},
};
},
};
const FunctionTypeNodeKind = 184;
const isFunctionTypeNode = (candidate) => {
return candidate.kind === FunctionTypeNodeKind;
};
function isReplaceWithCallback(methodName, callArguments, services) {
if (methodName === 'replace' && callArguments.length > 1) {
const type = (0, index_js_1.getTypeFromTreeNode)(callArguments[1], services);
const typeNode = services.program.getTypeChecker().typeToTypeNode(type, undefined, undefined);
return typeNode && isFunctionTypeNode(typeNode);
}
return false;
}
function reportDescriptor(methodName, node) {
if (methodName === 'map') {
return {
messageId: 'useForEach',
node,
};
}
else {
return {
messageId: 'returnValueMustBeUsed',
node,
data: { methodName },
};
}
}
function hasSideEffect(methodName, objectType, services) {
const typeAsString = typeToString(objectType, services);
if (typeAsString !== null) {
const methods = METHODS_WITHOUT_SIDE_EFFECTS[typeAsString];
return !methods?.has(methodName);
}
return true;
}
function typeToString(tp, services) {
const typechecker = services.program.getTypeChecker();
const baseType = typechecker.getBaseTypeOfLiteralType(tp);
const typeAsString = typechecker.typeToString(baseType);
if (typeAsString === 'number' || typeAsString === 'string') {
return typeAsString;
}
const symbol = tp.getSymbol();
if (symbol) {
const name = symbol.getName();
switch (name) {
case 'Array':
case 'Date':
case 'Math':
case 'RegExp':
return name.toLowerCase();
}
}
return null;
}