tools: move eslint from tools to tools/node_modules

This is required because we need to add the babel-eslint dependency
and it has to be able to resolve "eslint".
babel-eslint is required to support future ES features such as async
iterators and import.meta.

Refs: https://github.com/nodejs/node/pull/17755
PR-URL: https://github.com/nodejs/node/pull/17820
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/tools/node_modules/eslint/lib/rules/symbol-description.js b/tools/node_modules/eslint/lib/rules/symbol-description.js
new file mode 100644
index 0000000000..3f5ffd7463
--- /dev/null
+++ b/tools/node_modules/eslint/lib/rules/symbol-description.js
@@ -0,0 +1,66 @@
+/**
+ * @fileoverview Rule to enforce description with the `Symbol` object
+ * @author Jarek Rencz
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const astUtils = require("../ast-utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+
+module.exports = {
+    meta: {
+        docs: {
+            description: "require symbol descriptions",
+            category: "ECMAScript 6",
+            recommended: false
+        },
+
+        schema: []
+    },
+
+    create(context) {
+
+        /**
+         * Reports if node does not conform the rule in case rule is set to
+         * report missing description
+         *
+         * @param {ASTNode} node - A CallExpression node to check.
+         * @returns {void}
+         */
+        function checkArgument(node) {
+            if (node.arguments.length === 0) {
+                context.report({
+                    node,
+                    message: "Expected Symbol to have a description."
+                });
+            }
+        }
+
+        return {
+            "Program:exit"() {
+                const scope = context.getScope();
+                const variable = astUtils.getVariableByName(scope, "Symbol");
+
+                if (variable && variable.defs.length === 0) {
+                    variable.references.forEach(reference => {
+                        const node = reference.identifier;
+
+                        if (astUtils.isCallee(node)) {
+                            checkArgument(node.parent);
+                        }
+                    });
+                }
+            }
+        };
+
+    }
+};