| /** |
| * @fileoverview Rule to spot scenarios where a newline looks like it is ending a statement, but is not. |
| * @author Glen Mailer |
| */ |
| "use strict"; |
| |
| //------------------------------------------------------------------------------ |
| // Requirements |
| //------------------------------------------------------------------------------ |
| |
| const astUtils = require("../ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| docs: { |
| description: "disallow confusing multiline expressions", |
| category: "Possible Errors", |
| recommended: true, |
| url: "https://eslint.org/docs/rules/no-unexpected-multiline" |
| }, |
| |
| schema: [] |
| }, |
| |
| create(context) { |
| |
| const FUNCTION_MESSAGE = "Unexpected newline between function and ( of function call."; |
| const PROPERTY_MESSAGE = "Unexpected newline between object and [ of property access."; |
| const TAGGED_TEMPLATE_MESSAGE = "Unexpected newline between template tag and template literal."; |
| const DIVISION_MESSAGE = "Unexpected newline between numerator and division operator."; |
| |
| const REGEX_FLAG_MATCHER = /^[gimsuy]+$/; |
| |
| const sourceCode = context.getSourceCode(); |
| |
| /** |
| * Check to see if there is a newline between the node and the following open bracket |
| * line's expression |
| * @param {ASTNode} node The node to check. |
| * @param {string} msg The error message to use. |
| * @returns {void} |
| * @private |
| */ |
| function checkForBreakAfter(node, msg) { |
| const openParen = sourceCode.getTokenAfter(node, astUtils.isNotClosingParenToken); |
| const nodeExpressionEnd = sourceCode.getTokenBefore(openParen); |
| |
| if (openParen.loc.start.line !== nodeExpressionEnd.loc.end.line) { |
| context.report({ node, loc: openParen.loc.start, message: msg, data: { char: openParen.value } }); |
| } |
| } |
| |
| //-------------------------------------------------------------------------- |
| // Public API |
| //-------------------------------------------------------------------------- |
| |
| return { |
| |
| MemberExpression(node) { |
| if (!node.computed) { |
| return; |
| } |
| checkForBreakAfter(node.object, PROPERTY_MESSAGE); |
| }, |
| |
| TaggedTemplateExpression(node) { |
| if (node.tag.loc.end.line === node.quasi.loc.start.line) { |
| return; |
| } |
| context.report({ node, loc: node.loc.start, message: TAGGED_TEMPLATE_MESSAGE }); |
| }, |
| |
| CallExpression(node) { |
| if (node.arguments.length === 0) { |
| return; |
| } |
| checkForBreakAfter(node.callee, FUNCTION_MESSAGE); |
| }, |
| |
| "BinaryExpression[operator='/'] > BinaryExpression[operator='/'].left"(node) { |
| const secondSlash = sourceCode.getTokenAfter(node, token => token.value === "/"); |
| const tokenAfterOperator = sourceCode.getTokenAfter(secondSlash); |
| |
| if ( |
| tokenAfterOperator.type === "Identifier" && |
| REGEX_FLAG_MATCHER.test(tokenAfterOperator.value) && |
| secondSlash.range[1] === tokenAfterOperator.range[0] |
| ) { |
| checkForBreakAfter(node.left, DIVISION_MESSAGE); |
| } |
| } |
| }; |
| |
| } |
| }; |