2025-04-19 23:12:19 -04:00

370 lines
11 KiB
JavaScript

/**
* @fileoverview Rule to enforce getter and setter pairs in objects and classes.
* @author Gyandeep Singh
*/
'use strict';
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const astUtils = require('./utils/ast-utils');
//------------------------------------------------------------------------------
// Typedefs
//------------------------------------------------------------------------------
/**
* Property name if it can be computed statically, otherwise the list of the tokens of the key node.
* @typedef {string|Token[]} Key
*/
/**
* Accessor nodes with the same key.
* @typedef {Object} AccessorData
* @property {Key} key Accessor's key
* @property {ASTNode[]} getters List of getter nodes.
* @property {ASTNode[]} setters List of setter nodes.
*/
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
/**
* Checks whether or not the given lists represent the equal tokens in the same order.
* Tokens are compared by their properties, not by instance.
* @param {Token[]} left First list of tokens.
* @param {Token[]} right Second list of tokens.
* @returns {boolean} `true` if the lists have same tokens.
*/
function areEqualTokenLists(left, right) {
if (left.length !== right.length) {
return false;
}
for (let i = 0; i < left.length; i++) {
const leftToken = left[i],
rightToken = right[i];
if (
leftToken.type !== rightToken.type ||
leftToken.value !== rightToken.value
) {
return false;
}
}
return true;
}
/**
* Checks whether or not the given keys are equal.
* @param {Key} left First key.
* @param {Key} right Second key.
* @returns {boolean} `true` if the keys are equal.
*/
function areEqualKeys(left, right) {
if (typeof left === 'string' && typeof right === 'string') {
// Statically computed names.
return left === right;
}
if (Array.isArray(left) && Array.isArray(right)) {
// Token lists.
return areEqualTokenLists(left, right);
}
return false;
}
/**
* Checks whether or not a given node is of an accessor kind ('get' or 'set').
* @param {ASTNode} node A node to check.
* @returns {boolean} `true` if the node is of an accessor kind.
*/
function isAccessorKind(node) {
return node.kind === 'get' || node.kind === 'set';
}
/**
* Checks whether or not a given node is an argument of a specified method call.
* @param {ASTNode} node A node to check.
* @param {number} index An expected index of the node in arguments.
* @param {string} object An expected name of the object of the method.
* @param {string} property An expected name of the method.
* @returns {boolean} `true` if the node is an argument of the specified method call.
*/
function isArgumentOfMethodCall(node, index, object, property) {
const parent = node.parent;
return (
parent.type === 'CallExpression' &&
astUtils.isSpecificMemberAccess(parent.callee, object, property) &&
parent.arguments[index] === node
);
}
/**
* Checks whether or not a given node is a property descriptor.
* @param {ASTNode} node A node to check.
* @returns {boolean} `true` if the node is a property descriptor.
*/
function isPropertyDescriptor(node) {
// Object.defineProperty(obj, "foo", {set: ...})
if (
isArgumentOfMethodCall(node, 2, 'Object', 'defineProperty') ||
isArgumentOfMethodCall(node, 2, 'Reflect', 'defineProperty')
) {
return true;
}
/*
* Object.defineProperties(obj, {foo: {set: ...}})
* Object.create(proto, {foo: {set: ...}})
*/
const grandparent = node.parent.parent;
return (
grandparent.type === 'ObjectExpression' &&
(isArgumentOfMethodCall(grandparent, 1, 'Object', 'create') ||
isArgumentOfMethodCall(grandparent, 1, 'Object', 'defineProperties'))
);
}
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
type: 'suggestion',
defaultOptions: [
{
enforceForClassMembers: true,
getWithoutSet: false,
setWithoutGet: true,
},
],
docs: {
description: 'Enforce getter and setter pairs in objects and classes',
recommended: false,
url: 'https://eslint.org/docs/latest/rules/accessor-pairs',
},
schema: [
{
type: 'object',
properties: {
getWithoutSet: {
type: 'boolean',
},
setWithoutGet: {
type: 'boolean',
},
enforceForClassMembers: {
type: 'boolean',
},
},
additionalProperties: false,
},
],
messages: {
missingGetterInPropertyDescriptor:
'Getter is not present in property descriptor.',
missingSetterInPropertyDescriptor:
'Setter is not present in property descriptor.',
missingGetterInObjectLiteral: 'Getter is not present for {{ name }}.',
missingSetterInObjectLiteral: 'Setter is not present for {{ name }}.',
missingGetterInClass: 'Getter is not present for class {{ name }}.',
missingSetterInClass: 'Setter is not present for class {{ name }}.',
},
},
create(context) {
const [
{
getWithoutSet: checkGetWithoutSet,
setWithoutGet: checkSetWithoutGet,
enforceForClassMembers,
},
] = context.options;
const sourceCode = context.sourceCode;
/**
* Reports the given node.
* @param {ASTNode} node The node to report.
* @param {string} messageKind "missingGetter" or "missingSetter".
* @returns {void}
* @private
*/
function report(node, messageKind) {
if (node.type === 'Property') {
context.report({
node,
messageId: `${messageKind}InObjectLiteral`,
loc: astUtils.getFunctionHeadLoc(node.value, sourceCode),
data: {
name: astUtils.getFunctionNameWithKind(node.value),
},
});
} else if (node.type === 'MethodDefinition') {
context.report({
node,
messageId: `${messageKind}InClass`,
loc: astUtils.getFunctionHeadLoc(node.value, sourceCode),
data: {
name: astUtils.getFunctionNameWithKind(node.value),
},
});
} else {
context.report({
node,
messageId: `${messageKind}InPropertyDescriptor`,
});
}
}
/**
* Reports each of the nodes in the given list using the same messageId.
* @param {ASTNode[]} nodes Nodes to report.
* @param {string} messageKind "missingGetter" or "missingSetter".
* @returns {void}
* @private
*/
function reportList(nodes, messageKind) {
for (const node of nodes) {
report(node, messageKind);
}
}
/**
* Checks accessor pairs in the given list of nodes.
* @param {ASTNode[]} nodes The list to check.
* @returns {void}
* @private
*/
function checkList(nodes) {
const accessors = [];
let found = false;
for (let i = 0; i < nodes.length; i++) {
const node = nodes[i];
if (isAccessorKind(node)) {
// Creates a new `AccessorData` object for the given getter or setter node.
const name = astUtils.getStaticPropertyName(node);
const key = name !== null ? name : sourceCode.getTokens(node.key);
// Merges the given `AccessorData` object into the given accessors list.
for (let j = 0; j < accessors.length; j++) {
const accessor = accessors[j];
if (areEqualKeys(accessor.key, key)) {
accessor.getters.push(...(node.kind === 'get' ? [node] : []));
accessor.setters.push(...(node.kind === 'set' ? [node] : []));
found = true;
break;
}
}
if (!found) {
accessors.push({
key,
getters: node.kind === 'get' ? [node] : [],
setters: node.kind === 'set' ? [node] : [],
});
}
found = false;
}
}
for (const { getters, setters } of accessors) {
if (checkSetWithoutGet && setters.length && !getters.length) {
reportList(setters, 'missingGetter');
}
if (checkGetWithoutSet && getters.length && !setters.length) {
reportList(getters, 'missingSetter');
}
}
}
/**
* Checks accessor pairs in an object literal.
* @param {ASTNode} node `ObjectExpression` node to check.
* @returns {void}
* @private
*/
function checkObjectLiteral(node) {
checkList(node.properties.filter((p) => p.type === 'Property'));
}
/**
* Checks accessor pairs in a property descriptor.
* @param {ASTNode} node Property descriptor `ObjectExpression` node to check.
* @returns {void}
* @private
*/
function checkPropertyDescriptor(node) {
const namesToCheck = new Set(
node.properties
.filter(
(p) => p.type === 'Property' && p.kind === 'init' && !p.computed
)
.map(({ key }) => key.name)
);
const hasGetter = namesToCheck.has('get');
const hasSetter = namesToCheck.has('set');
if (checkSetWithoutGet && hasSetter && !hasGetter) {
report(node, 'missingGetter');
}
if (checkGetWithoutSet && hasGetter && !hasSetter) {
report(node, 'missingSetter');
}
}
/**
* Checks the given object expression as an object literal and as a possible property descriptor.
* @param {ASTNode} node `ObjectExpression` node to check.
* @returns {void}
* @private
*/
function checkObjectExpression(node) {
checkObjectLiteral(node);
if (isPropertyDescriptor(node)) {
checkPropertyDescriptor(node);
}
}
/**
* Checks the given class body.
* @param {ASTNode} node `ClassBody` node to check.
* @returns {void}
* @private
*/
function checkClassBody(node) {
const methodDefinitions = node.body.filter(
(m) => m.type === 'MethodDefinition'
);
checkList(methodDefinitions.filter((m) => m.static));
checkList(methodDefinitions.filter((m) => !m.static));
}
const listeners = {};
if (checkSetWithoutGet || checkGetWithoutSet) {
listeners.ObjectExpression = checkObjectExpression;
if (enforceForClassMembers) {
listeners.ClassBody = checkClassBody;
}
}
return listeners;
},
};