/**
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								 * @fileoverview Rule to flag the generator functions that does not have yield.
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								 * @author Toru Nagashima
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								 */
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								"use strict";
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								//------------------------------------------------------------------------------
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								// Rule Definition
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								//------------------------------------------------------------------------------
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								/** @type {import('../shared/types').Rule} */
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								module.exports = {
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								    meta: {
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								        type: "suggestion",
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								        docs: {
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								            description: "Require generator functions to contain `yield`",
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								            recommended: true,
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								            url: "https://eslint.org/docs/latest/rules/require-yield"
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								        },
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								        schema: [],
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								        messages: {
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								            missingYield: "This generator function does not have 'yield'."
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								        }
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								    },
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								    create(context) {
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								        const stack = [];
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								        /**
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								         * If the node is a generator function, start counting `yield` keywords.
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								         * @param {Node} node A function node to check.
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								         * @returns {void}
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								         */
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								        function beginChecking(node) {
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								            if (node.generator) {
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								                stack.push(0);
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								            }
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								        }
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								        /**
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								         * If the node is a generator function, end counting `yield` keywords, then
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								         * reports result.
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								         * @param {Node} node A function node to check.
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								         * @returns {void}
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								         */
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								        function endChecking(node) {
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								            if (!node.generator) {
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								                return;
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								            }
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								            const countYield = stack.pop();
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								            if (countYield === 0 && node.body.body.length > 0) {
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								                context.report({ node, messageId: "missingYield" });
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								            }
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								        }
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								        return {
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								            FunctionDeclaration: beginChecking,
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								            "FunctionDeclaration:exit": endChecking,
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								            FunctionExpression: beginChecking,
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								            "FunctionExpression:exit": endChecking,
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								            // Increases the count of `yield` keyword.
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								            YieldExpression() {
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								                if (stack.length > 0) {
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								                    stack[stack.length - 1] += 1;
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								                }
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								            }
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								        };
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								    }
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								};
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