import {hasSideEffect, isSemicolonToken} from '@eslint-community/eslint-utils'; import { getCallExpressionTokens, getCallExpressionArgumentsText, isSameReference, isNodeMatches, getPreviousNode, } from './utils/index.js'; import {isMethodCall, isMemberExpression, isCallExpression} from './ast/index.js'; const ERROR = 'error/array-push'; const SUGGESTION = 'suggestion'; const messages = { [ERROR]: 'Do not call `{{description}}` multiple times.', [SUGGESTION]: 'Merge with previous one.', }; const isClassList = node => isMemberExpression(node, { property: 'classList', computed: false, }); const cases = [ { description: 'Array#push()', test: callExpression => isMethodCall(callExpression, { method: 'push', optionalCall: false, }), ignore: [ 'stream.push', 'this.push', 'this.stream.push', 'process.stdin.push', 'process.stdout.push', 'process.stderr.push', ], }, { description: 'Element#classList.add()', test: callExpression => isMethodCall(callExpression, { method: 'add', optionalCall: false, optionalMember: false, }) && isClassList(callExpression.callee.object), }, { description: 'Element#classList.remove()', test: callExpression => isMethodCall(callExpression, { method: 'remove', optionalCall: false, optionalMember: false, }) && isClassList(callExpression.callee.object), }, { description: 'importScripts()', test: callExpression => isCallExpression(callExpression, {name: 'importScripts'}), }, ]; function create(context) { const { ignore: ignoredCalleeInOptions, } = { ignore: [], ...context.options[0], }; const {sourceCode} = context; return { * CallExpression(secondCall) { for (const {description, test, ignore = []} of cases) { if (!test(secondCall)) { continue; } const ignoredCallee = [...ignore, ...ignoredCalleeInOptions]; if (isNodeMatches(secondCall.callee, ignoredCallee)) { continue; } let secondExpressionStatement = secondCall.parent; if (secondExpressionStatement.type === 'ChainExpression' && secondCall === secondExpressionStatement.expression) { secondExpressionStatement = secondExpressionStatement.parent; } if (secondExpressionStatement.type !== 'ExpressionStatement') { continue; } const firstExpressionStatement = getPreviousNode(secondExpressionStatement, context); if (firstExpressionStatement?.type !== 'ExpressionStatement') { continue; } let firstCall = firstExpressionStatement.expression; if (firstCall.type === 'ChainExpression') { firstCall = firstCall.expression; } if (!test(firstCall) || !isSameReference(firstCall.callee, secondCall.callee)) { continue; } const secondCallArguments = secondCall.arguments; const problem = { node: secondCall.callee.type === 'Identifier' ? secondCall.callee : secondCall.callee.property, messageId: ERROR, data: {description}, }; const fix = function * (fixer) { if (secondCallArguments.length > 0) { const text = getCallExpressionArgumentsText(context, secondCall); const { trailingCommaToken, closingParenthesisToken, } = getCallExpressionTokens(firstCall, context); yield ( trailingCommaToken ? fixer.insertTextAfter(trailingCommaToken, ` ${text}`) : fixer.insertTextBefore(closingParenthesisToken, firstCall.arguments.length > 0 ? `, ${text}` : text) ); } const shouldKeepSemicolon = !isSemicolonToken(sourceCode.getLastToken(firstExpressionStatement)) && isSemicolonToken(sourceCode.getLastToken(secondExpressionStatement)); const [, start] = sourceCode.getRange(firstExpressionStatement); const [, end] = sourceCode.getRange(secondExpressionStatement); yield fixer.replaceTextRange([start, end], shouldKeepSemicolon ? ';' : ''); }; if (secondCallArguments.some(element => hasSideEffect(element, sourceCode))) { problem.suggest = [ { messageId: SUGGESTION, fix, }, ]; } else { problem.fix = fix; } yield problem; } }, }; } const schema = [ { type: 'object', additionalProperties: false, properties: { ignore: { type: 'array', uniqueItems: true, }, }, }, ]; /** @type {import('eslint').Rule.RuleModule} */ const config = { create, meta: { type: 'suggestion', docs: { description: 'Enforce combining multiple `Array#push()`, `Element#classList.{add,remove}()`, and `importScripts()` into one call.', recommended: 'unopinionated', }, fixable: 'code', hasSuggestions: true, schema, defaultOptions: [{}], messages, }, }; export default config;