Add components

slider/node_modules/eslint/lib/rules/eqeqeq.js

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+/**
+ * @fileoverview Rule to flag statements that use != and == instead of !== and ===
+ * @author Nicholas C. Zakas
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const astUtils = require("./utils/ast-utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+/** @type {import('../types').Rule.RuleModule} */
+module.exports = {
+	meta: {
+		type: "suggestion",
+		hasSuggestions: true,
+
+		docs: {
+			description: "Require the use of `===` and `!==`",
+			recommended: false,
+			url: "https://eslint.org/docs/latest/rules/eqeqeq",
+		},
+
+		schema: {
+			anyOf: [
+				{
+					type: "array",
+					items: [
+						{
+							enum: ["always"],
+						},
+						{
+							type: "object",
+							properties: {
+								null: {
+									enum: ["always", "never", "ignore"],
+								},
+							},
+							additionalProperties: false,
+						},
+					],
+					additionalItems: false,
+				},
+				{
+					type: "array",
+					items: [
+						{
+							enum: ["smart", "allow-null"],
+						},
+					],
+					additionalItems: false,
+				},
+			],
+		},
+
+		fixable: "code",
+
+		messages: {
+			unexpected:
+				"Expected '{{expectedOperator}}' and instead saw '{{actualOperator}}'.",
+			replaceOperator:
+				"Use '{{expectedOperator}}' instead of '{{actualOperator}}'.",
+		},
+	},
+
+	create(context) {
+		const config = context.options[0] || "always";
+		const options = context.options[1] || {};
+		const sourceCode = context.sourceCode;
+
+		const nullOption =
+			config === "always" ? options.null || "always" : "ignore";
+		const enforceRuleForNull = nullOption === "always";
+		const enforceInverseRuleForNull = nullOption === "never";
+
+		/**
+		 * Checks if an expression is a typeof expression
+		 * @param {ASTNode} node The node to check
+		 * @returns {boolean} if the node is a typeof expression
+		 */
+		function isTypeOf(node) {
+			return (
+				node.type === "UnaryExpression" && node.operator === "typeof"
+			);
+		}
+
+		/**
+		 * Checks if either operand of a binary expression is a typeof operation
+		 * @param {ASTNode} node The node to check
+		 * @returns {boolean} if one of the operands is typeof
+		 * @private
+		 */
+		function isTypeOfBinary(node) {
+			return isTypeOf(node.left) || isTypeOf(node.right);
+		}
+
+		/**
+		 * Checks if operands are literals of the same type (via typeof)
+		 * @param {ASTNode} node The node to check
+		 * @returns {boolean} if operands are of same type
+		 * @private
+		 */
+		function areLiteralsAndSameType(node) {
+			return (
+				node.left.type === "Literal" &&
+				node.right.type === "Literal" &&
+				typeof node.left.value === typeof node.right.value
+			);
+		}
+
+		/**
+		 * Checks if one of the operands is a literal null
+		 * @param {ASTNode} node The node to check
+		 * @returns {boolean} if operands are null
+		 * @private
+		 */
+		function isNullCheck(node) {
+			return (
+				astUtils.isNullLiteral(node.right) ||
+				astUtils.isNullLiteral(node.left)
+			);
+		}
+
+		/**
+		 * Reports a message for this rule.
+		 * @param {ASTNode} node The binary expression node that was checked
+		 * @param {string} expectedOperator The operator that was expected (either '==', '!=', '===', or '!==')
+		 * @returns {void}
+		 * @private
+		 */
+		function report(node, expectedOperator) {
+			const operatorToken = sourceCode.getFirstTokenBetween(
+				node.left,
+				node.right,
+				token => token.value === node.operator,
+			);
+
+			const commonReportParams = {
+				node,
+				loc: operatorToken.loc,
+				messageId: "unexpected",
+				data: { expectedOperator, actualOperator: node.operator },
+			};
+
+			if (isTypeOfBinary(node) || areLiteralsAndSameType(node)) {
+				context.report({
+					...commonReportParams,
+					fix(fixer) {
+						return fixer.replaceText(
+							operatorToken,
+							expectedOperator,
+						);
+					},
+				});
+			} else {
+				context.report({
+					...commonReportParams,
+					suggest: [
+						{
+							messageId: "replaceOperator",
+							data: {
+								expectedOperator,
+								actualOperator: node.operator,
+							},
+							fix: fixer =>
+								fixer.replaceText(
+									operatorToken,
+									expectedOperator,
+								),
+						},
+					],
+				});
+			}
+		}
+
+		return {
+			BinaryExpression(node) {
+				const isNull = isNullCheck(node);
+
+				if (node.operator !== "==" && node.operator !== "!=") {
+					if (enforceInverseRuleForNull && isNull) {
+						report(node, node.operator.slice(0, -1));
+					}
+					return;
+				}
+
+				if (
+					config === "smart" &&
+					(isTypeOfBinary(node) ||
+						areLiteralsAndSameType(node) ||
+						isNull)
+				) {
+					return;
+				}
+
+				if (!enforceRuleForNull && isNull) {
+					return;
+				}
+
+				report(node, `${node.operator}=`);
+			},
+		};
+	},
+};