1 files changed, 149 insertions, 0 deletions
diff --git a/tools/node_modules/eslint/lib/rules/arrow-spacing.js b/tools/node_modules/eslint/lib/rules/arrow-spacing.js
new file mode 100644
index 0000000000..37e03907cb
--- /dev/null
+++ b/tools/node_modules/eslint/lib/rules/arrow-spacing.js
@@ -0,0 +1,149 @@
+/**
+ * @fileoverview Rule to define spacing before/after arrow function's arrow.
+ * @author Jxck
+ */
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const astUtils = require("../ast-utils");
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+    meta: {
+        docs: {
+            description: "enforce consistent spacing before and after the arrow in arrow functions",
+            category: "ECMAScript 6",
+            recommended: false
+        },
+
+        fixable: "whitespace",
+
+        schema: [
+            {
+                type: "object",
+                properties: {
+                    before: {
+                        type: "boolean"
+                    },
+                    after: {
+                        type: "boolean"
+                    }
+                },
+                additionalProperties: false
+            }
+        ]
+    },
+
+    create(context) {
+
+        // merge rules with default
+        const rule = { before: true, after: true },
+            option = context.options[0] || {};
+
+        rule.before = option.before !== false;
+        rule.after = option.after !== false;
+
+        const sourceCode = context.getSourceCode();
+
+        /**
+         * Get tokens of arrow(`=>`) and before/after arrow.
+         * @param {ASTNode} node The arrow function node.
+         * @returns {Object} Tokens of arrow and before/after arrow.
+         */
+        function getTokens(node) {
+            const arrow = sourceCode.getTokenBefore(node.body, astUtils.isArrowToken);
+
+            return {
+                before: sourceCode.getTokenBefore(arrow),
+                arrow,
+                after: sourceCode.getTokenAfter(arrow)
+            };
+        }
+
+        /**
+         * Count spaces before/after arrow(`=>`) token.
+         * @param {Object} tokens Tokens before/after arrow.
+         * @returns {Object} count of space before/after arrow.
+         */
+        function countSpaces(tokens) {
+            const before = tokens.arrow.range[0] - tokens.before.range[1];
+            const after = tokens.after.range[0] - tokens.arrow.range[1];
+
+            return { before, after };
+        }
+
+        /**
+         * Determines whether space(s) before after arrow(`=>`) is satisfy rule.
+         * if before/after value is `true`, there should be space(s).
+         * if before/after value is `false`, there should be no space.
+         * @param {ASTNode} node The arrow function node.
+         * @returns {void}
+         */
+        function spaces(node) {
+            const tokens = getTokens(node);
+            const countSpace = countSpaces(tokens);
+
+            if (rule.before) {
+
+                // should be space(s) before arrow
+                if (countSpace.before === 0) {
+                    context.report({
+                        node: tokens.before,
+                        message: "Missing space before =>.",
+                        fix(fixer) {
+                            return fixer.insertTextBefore(tokens.arrow, " ");
+                        }
+                    });
+                }
+            } else {
+
+                // should be no space before arrow
+                if (countSpace.before > 0) {
+                    context.report({
+                        node: tokens.before,
+                        message: "Unexpected space before =>.",
+                        fix(fixer) {
+                            return fixer.removeRange([tokens.before.range[1], tokens.arrow.range[0]]);
+                        }
+                    });
+                }
+            }
+
+            if (rule.after) {
+
+                // should be space(s) after arrow
+                if (countSpace.after === 0) {
+                    context.report({
+                        node: tokens.after,
+                        message: "Missing space after =>.",
+                        fix(fixer) {
+                            return fixer.insertTextAfter(tokens.arrow, " ");
+                        }
+                    });
+                }
+            } else {
+
+                // should be no space after arrow
+                if (countSpace.after > 0) {
+                    context.report({
+                        node: tokens.after,
+                        message: "Unexpected space after =>.",
+                        fix(fixer) {
+                            return fixer.removeRange([tokens.arrow.range[1], tokens.after.range[0]]);
+                        }
+                    });
+                }
+            }
+        }
+
+        return {
+            ArrowFunctionExpression: spaces
+        };
+    }
+};