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, 89 insertions, 0 deletions

diff --git a/tools/node_modules/eslint/lib/rules/multiline-ternary.js b/tools/node_modules/eslint/lib/rules/multiline-ternary.js
new file mode 100644
index 0000000000..a74f241d86
--- /dev/null
+++ b/tools/node_modules/eslint/lib/rules/multiline-ternary.js
@@ -0,0 +1,89 @@
+/**
+ * @fileoverview Enforce newlines between operands of ternary expressions
+ * @author Kai Cataldo
+ */
+
+"use strict";
+
+const astUtils = require("../ast-utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+    meta: {
+        docs: {
+            description: "enforce newlines between operands of ternary expressions",
+            category: "Stylistic Issues",
+            recommended: false
+        },
+        schema: [
+            {
+                enum: ["always", "always-multiline", "never"]
+            }
+        ]
+    },
+
+    create(context) {
+        const option = context.options[0];
+        const multiline = option !== "never";
+        const allowSingleLine = option === "always-multiline";
+
+        //--------------------------------------------------------------------------
+        // Helpers
+        //--------------------------------------------------------------------------
+
+        /**
+         * Tests whether node is preceded by supplied tokens
+         * @param {ASTNode} node - node to check
+         * @param {ASTNode} parentNode - parent of node to report
+         * @param {boolean} expected - whether newline was expected or not
+         * @returns {void}
+         * @private
+         */
+        function reportError(node, parentNode, expected) {
+            context.report({
+                node,
+                message: "{{expected}} newline between {{typeOfError}} of ternary expression.",
+                data: {
+                    expected: expected ? "Expected" : "Unexpected",
+                    typeOfError: node === parentNode.test ? "test and consequent" : "consequent and alternate"
+                }
+            });
+        }
+
+        //--------------------------------------------------------------------------
+        // Public
+        //--------------------------------------------------------------------------
+
+        return {
+            ConditionalExpression(node) {
+                const areTestAndConsequentOnSameLine = astUtils.isTokenOnSameLine(node.test, node.consequent);
+                const areConsequentAndAlternateOnSameLine = astUtils.isTokenOnSameLine(node.consequent, node.alternate);
+
+                if (!multiline) {
+                    if (!areTestAndConsequentOnSameLine) {
+                        reportError(node.test, node, false);
+                    }
+
+                    if (!areConsequentAndAlternateOnSameLine) {
+                        reportError(node.consequent, node, false);
+                    }
+                } else {
+                    if (allowSingleLine && node.loc.start.line === node.loc.end.line) {
+                        return;
+                    }
+
+                    if (areTestAndConsequentOnSameLine) {
+                        reportError(node.test, node, true);
+                    }
+
+                    if (areConsequentAndAlternateOnSameLine) {
+                        reportError(node.consequent, node, true);
+                    }
+                }
+            }
+        };
+    }
+};