no-import-assign.js

/**
 * @fileoverview Rule to flag updates of imported bindings.
 * @author Toru Nagashima <https://github.com/mysticatea>
 */

"use strict";

//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------

const { findVariable } = require("eslint-utils");
const astUtils = require("./utils/ast-utils");

const WellKnownMutationFunctions = {
    Object: /^(?:assign|definePropert(?:y|ies)|freeze|setPrototypeOf)$/u,
    Reflect: /^(?:(?:define|delete)Property|set(?:PrototypeOf)?)$/u
};

/**
 * Check if a given node is LHS of an assignment node.
 * @param {ASTNode} node The node to check.
 * @returns {boolean} `true` if the node is LHS.
 */
function isAssignmentLeft(node) {
    const { parent } = node;

    return (
        (
            parent.type === "AssignmentExpression" &&
            parent.left === node
        ) ||

        // Destructuring assignments
        parent.type === "ArrayPattern" ||
        (
            parent.type === "Property" &&
            parent.value === node &&
            parent.parent.type === "ObjectPattern"
        ) ||
        parent.type === "RestElement" ||
        (
            parent.type === "AssignmentPattern" &&
            parent.left === node
        )
    );
}

/**
 * Check if a given node is the operand of mutation unary operator.
 * @param {ASTNode} node The node to check.
 * @returns {boolean} `true` if the node is the operand of mutation unary operator.
 */
function isOperandOfMutationUnaryOperator(node) {
    const argumentNode = node.parent.type === "ChainExpression"
        ? node.parent
        : node;
    const { parent } = argumentNode;

    return (
        (
            parent.type === "UpdateExpression" &&
            parent.argument === argumentNode
        ) ||
        (
            parent.type === "UnaryExpression" &&
            parent.operator === "delete" &&
            parent.argument === argumentNode
        )
    );