Add components

slider/node_modules/eslint/lib/rules/no-constant-condition.js

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+/**
+ * @fileoverview Rule to flag use constant conditions
+ * @author Christian Schulz <http://rndm.de>
+ */
+
+"use strict";
+
+const { isConstant } = require("./utils/ast-utils");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+/** @type {import('../types').Rule.RuleModule} */
+module.exports = {
+	meta: {
+		type: "problem",
+
+		defaultOptions: [{ checkLoops: "allExceptWhileTrue" }],
+
+		docs: {
+			description: "Disallow constant expressions in conditions",
+			recommended: true,
+			url: "https://eslint.org/docs/latest/rules/no-constant-condition",
+		},
+
+		schema: [
+			{
+				type: "object",
+				properties: {
+					checkLoops: {
+						enum: [
+							"all",
+							"allExceptWhileTrue",
+							"none",
+							true,
+							false,
+						],
+					},
+				},
+				additionalProperties: false,
+			},
+		],
+
+		messages: {
+			unexpected: "Unexpected constant condition.",
+		},
+	},
+
+	create(context) {
+		const loopSetStack = [];
+		const sourceCode = context.sourceCode;
+		let [{ checkLoops }] = context.options;
+
+		if (checkLoops === true) {
+			checkLoops = "all";
+		} else if (checkLoops === false) {
+			checkLoops = "none";
+		}
+
+		let loopsInCurrentScope = new Set();
+
+		//--------------------------------------------------------------------------
+		// Helpers
+		//--------------------------------------------------------------------------
+
+		/**
+		 * Tracks when the given node contains a constant condition.
+		 * @param {ASTNode} node The AST node to check.
+		 * @returns {void}
+		 * @private
+		 */
+		function trackConstantConditionLoop(node) {
+			if (
+				node.test &&
+				isConstant(sourceCode.getScope(node), node.test, true)
+			) {
+				loopsInCurrentScope.add(node);
+			}
+		}
+
+		/**
+		 * Reports when the set contains the given constant condition node
+		 * @param {ASTNode} node The AST node to check.
+		 * @returns {void}
+		 * @private
+		 */
+		function checkConstantConditionLoopInSet(node) {
+			if (loopsInCurrentScope.has(node)) {
+				loopsInCurrentScope.delete(node);
+				context.report({ node: node.test, messageId: "unexpected" });
+			}
+		}
+
+		/**
+		 * Reports when the given node contains a constant condition.
+		 * @param {ASTNode} node The AST node to check.
+		 * @returns {void}
+		 * @private
+		 */
+		function reportIfConstant(node) {
+			if (
+				node.test &&
+				isConstant(sourceCode.getScope(node), node.test, true)
+			) {
+				context.report({ node: node.test, messageId: "unexpected" });
+			}
+		}
+
+		/**
+		 * Stores current set of constant loops in loopSetStack temporarily
+		 * and uses a new set to track constant loops
+		 * @returns {void}
+		 * @private
+		 */
+		function enterFunction() {
+			loopSetStack.push(loopsInCurrentScope);
+			loopsInCurrentScope = new Set();
+		}
+
+		/**
+		 * Reports when the set still contains stored constant conditions
+		 * @returns {void}
+		 * @private
+		 */
+		function exitFunction() {
+			loopsInCurrentScope = loopSetStack.pop();
+		}
+
+		/**
+		 * Checks node when checkLoops option is enabled
+		 * @param {ASTNode} node The AST node to check.
+		 * @returns {void}
+		 * @private
+		 */
+		function checkLoop(node) {
+			if (checkLoops === "all" || checkLoops === "allExceptWhileTrue") {
+				trackConstantConditionLoop(node);
+			}
+		}
+
+		//--------------------------------------------------------------------------
+		// Public
+		//--------------------------------------------------------------------------
+
+		return {
+			ConditionalExpression: reportIfConstant,
+			IfStatement: reportIfConstant,
+			WhileStatement(node) {
+				if (
+					node.test.type === "Literal" &&
+					node.test.value === true &&
+					checkLoops === "allExceptWhileTrue"
+				) {
+					return;
+				}
+
+				checkLoop(node);
+			},
+			"WhileStatement:exit": checkConstantConditionLoopInSet,
+			DoWhileStatement: checkLoop,
+			"DoWhileStatement:exit": checkConstantConditionLoopInSet,
+			ForStatement: checkLoop,
+			"ForStatement > .test": node => checkLoop(node.parent),
+			"ForStatement:exit": checkConstantConditionLoopInSet,
+			FunctionDeclaration: enterFunction,
+			"FunctionDeclaration:exit": exitFunction,
+			FunctionExpression: enterFunction,
+			"FunctionExpression:exit": exitFunction,
+			YieldExpression: () => loopsInCurrentScope.clear(),
+		};
+	},
+};