| /** |
| * @fileoverview Rule to ensure newline per method call when chaining calls |
| * @author Rajendra Patil |
| * @author Burak Yigit Kaya |
| */ |
| |
| "use strict"; |
| |
| const astUtils = require("./utils/ast-utils"); |
| |
| //------------------------------------------------------------------------------ |
| // Rule Definition |
| //------------------------------------------------------------------------------ |
| |
| module.exports = { |
| meta: { |
| type: "layout", |
| |
| docs: { |
| description: "require a newline after each call in a method chain", |
| category: "Stylistic Issues", |
| recommended: false, |
| url: "https://eslint.org/docs/rules/newline-per-chained-call" |
| }, |
| |
| fixable: "whitespace", |
| |
| schema: [{ |
| type: "object", |
| properties: { |
| ignoreChainWithDepth: { |
| type: "integer", |
| minimum: 1, |
| maximum: 10, |
| default: 2 |
| } |
| }, |
| additionalProperties: false |
| }], |
| messages: { |
| expected: "Expected line break before `{{callee}}`." |
| } |
| }, |
| |
| create(context) { |
| |
| const options = context.options[0] || {}, |
| ignoreChainWithDepth = options.ignoreChainWithDepth || 2; |
| |
| const sourceCode = context.getSourceCode(); |
| |
| /** |
| * Get the prefix of a given MemberExpression node. |
| * If the MemberExpression node is a computed value it returns a |
| * left bracket. If not it returns a period. |
| * |
| * @param {ASTNode} node - A MemberExpression node to get |
| * @returns {string} The prefix of the node. |
| */ |
| function getPrefix(node) { |
| return node.computed ? "[" : "."; |
| } |
| |
| /** |
| * Gets the property text of a given MemberExpression node. |
| * If the text is multiline, this returns only the first line. |
| * |
| * @param {ASTNode} node - A MemberExpression node to get. |
| * @returns {string} The property text of the node. |
| */ |
| function getPropertyText(node) { |
| const prefix = getPrefix(node); |
| const lines = sourceCode.getText(node.property).split(astUtils.LINEBREAK_MATCHER); |
| const suffix = node.computed && lines.length === 1 ? "]" : ""; |
| |
| return prefix + lines[0] + suffix; |
| } |
| |
| return { |
| "CallExpression:exit"(node) { |
| if (!node.callee || node.callee.type !== "MemberExpression") { |
| return; |
| } |
| |
| const callee = node.callee; |
| let parent = callee.object; |
| let depth = 1; |
| |
| while (parent && parent.callee) { |
| depth += 1; |
| parent = parent.callee.object; |
| } |
| |
| if (depth > ignoreChainWithDepth && astUtils.isTokenOnSameLine(callee.object, callee.property)) { |
| context.report({ |
| node: callee.property, |
| loc: callee.property.loc.start, |
| messageId: "expected", |
| data: { |
| callee: getPropertyText(callee) |
| }, |
| fix(fixer) { |
| const firstTokenAfterObject = sourceCode.getTokenAfter(callee.object, astUtils.isNotClosingParenToken); |
| |
| return fixer.insertTextBefore(firstTokenAfterObject, "\n"); |
| } |
| }); |
| } |
| } |
| }; |
| } |
| }; |