Add components

slider/node_modules/eslint/lib/rules/no-useless-call.js

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+/**
+ * @fileoverview A rule to disallow unnecessary `.call()` and `.apply()`.
+ * @author Toru Nagashima
+ */
+
+"use strict";
+
+const astUtils = require("./utils/ast-utils");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+/**
+ * Checks whether or not a node is a `.call()`/`.apply()`.
+ * @param {ASTNode} node A CallExpression node to check.
+ * @returns {boolean} Whether or not the node is a `.call()`/`.apply()`.
+ */
+function isCallOrNonVariadicApply(node) {
+	const callee = astUtils.skipChainExpression(node.callee);
+
+	return (
+		callee.type === "MemberExpression" &&
+		callee.property.type === "Identifier" &&
+		callee.computed === false &&
+		((callee.property.name === "call" && node.arguments.length >= 1) ||
+			(callee.property.name === "apply" &&
+				node.arguments.length === 2 &&
+				node.arguments[1].type === "ArrayExpression"))
+	);
+}
+
+/**
+ * Checks whether or not `thisArg` is not changed by `.call()`/`.apply()`.
+ * @param {ASTNode|null} expectedThis The node that is the owner of the applied function.
+ * @param {ASTNode} thisArg The node that is given to the first argument of the `.call()`/`.apply()`.
+ * @param {SourceCode} sourceCode The ESLint source code object.
+ * @returns {boolean} Whether or not `thisArg` is not changed by `.call()`/`.apply()`.
+ */
+function isValidThisArg(expectedThis, thisArg, sourceCode) {
+	if (!expectedThis) {
+		return astUtils.isNullOrUndefined(thisArg);
+	}
+	return astUtils.equalTokens(expectedThis, thisArg, sourceCode);
+}
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+/** @type {import('../types').Rule.RuleModule} */
+module.exports = {
+	meta: {
+		type: "suggestion",
+
+		docs: {
+			description:
+				"Disallow unnecessary calls to `.call()` and `.apply()`",
+			recommended: false,
+			url: "https://eslint.org/docs/latest/rules/no-useless-call",
+		},
+
+		schema: [],
+
+		messages: {
+			unnecessaryCall: "Unnecessary '.{{name}}()'.",
+		},
+	},
+
+	create(context) {
+		const sourceCode = context.sourceCode;
+
+		return {
+			CallExpression(node) {
+				if (!isCallOrNonVariadicApply(node)) {
+					return;
+				}
+
+				const callee = astUtils.skipChainExpression(node.callee);
+				const applied = astUtils.skipChainExpression(callee.object);
+				const expectedThis =
+					applied.type === "MemberExpression" ? applied.object : null;
+				const thisArg = node.arguments[0];
+
+				if (isValidThisArg(expectedThis, thisArg, sourceCode)) {
+					context.report({
+						node,
+						messageId: "unnecessaryCall",
+						data: { name: callee.property.name },
+					});
+				}
+			},
+		};
+	},
+};