GoScrobble/web/node_modules/eslint/lib/rules/accessor-pairs.js

355 lines
12 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
//------------------------------------------------------------------------------
module.exports = {
meta: {
type: "suggestion",
docs: {
description: "enforce getter and setter pairs in objects and classes",
category: "Best Practices",
recommended: false,
url: "https://eslint.org/docs/rules/accessor-pairs"
},
schema: [{
type: "object",
properties: {
getWithoutSet: {
type: "boolean",
default: false
},
setWithoutGet: {
type: "boolean",
default: true
},
enforceForClassMembers: {
type: "boolean",
default: true
}
},
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 config = context.options[0] || {};
const checkGetWithoutSet = config.getWithoutSet === true;
const checkSetWithoutGet = config.setWithoutGet !== false;
const enforceForClassMembers = config.enforceForClassMembers !== false;
const sourceCode = context.getSourceCode();
/**
* 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);
}
}
/**
* Creates a new `AccessorData` object for the given getter or setter node.
* @param {ASTNode} node A getter or setter node.
* @returns {AccessorData} New `AccessorData` object that contains the given node.
* @private
*/
function createAccessorData(node) {
const name = astUtils.getStaticPropertyName(node);
const key = (name !== null) ? name : sourceCode.getTokens(node.key);
return {
key,
getters: node.kind === "get" ? [node] : [],
setters: node.kind === "set" ? [node] : []
};
}
/**
* Merges the given `AccessorData` object into the given accessors list.
* @param {AccessorData[]} accessors The list to merge into.
* @param {AccessorData} accessorData The object to merge.
* @returns {AccessorData[]} The same instance with the merged object.
* @private
*/
function mergeAccessorData(accessors, accessorData) {
const equalKeyElement = accessors.find(a => areEqualKeys(a.key, accessorData.key));
if (equalKeyElement) {
equalKeyElement.getters.push(...accessorData.getters);
equalKeyElement.setters.push(...accessorData.setters);
} else {
accessors.push(accessorData);
}
return accessors;
}
/**
* Checks accessor pairs in the given list of nodes.
* @param {ASTNode[]} nodes The list to check.
* @returns {void}
* @private
*/
function checkList(nodes) {
const accessors = nodes
.filter(isAccessorKind)
.map(createAccessorData)
.reduce(mergeAccessorData, []);
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 = node.properties
.filter(p => p.type === "Property" && p.kind === "init" && !p.computed)
.map(({ key }) => key.name);
const hasGetter = namesToCheck.includes("get");
const hasSetter = namesToCheck.includes("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;
}
};