1 files changed, 70 insertions, 0 deletions
diff --git a/tools/eslint/lib/rules/generator-star.js b/tools/eslint/lib/rules/generator-star.js
new file mode 100644
index 0000000000..4541e6711c
--- /dev/null
+++ b/tools/eslint/lib/rules/generator-star.js
@@ -0,0 +1,70 @@
+/**
+ * @fileoverview Rule to check for the position of the * in your generator functions
+ * @author Jamund Ferguson
+ * @copyright 2014 Jamund Ferguson. All rights reserved.
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function(context) {
+
+    var position = context.options[0] || "end";
+
+    /**
+     * Check the position of the star compared to the expected position.
+     * @param {ASTNode} node - the entire function node
+     * @returns {void}
+     */
+    function checkStarPosition(node) {
+        var starToken;
+
+        if (!node.generator) {
+            return;
+        }
+
+        // Blocked, pending decision to fix or work around in eslint/espree#36
+        if (context.getAncestors().pop().method) {
+            return;
+        }
+
+        starToken = context.getFirstToken(node, 1);
+
+        // check for function *name() {}
+        if (position === "end") {
+
+            // * starts where the next identifier begins
+            if (starToken.range[1] !== context.getTokenAfter(starToken).range[0]) {
+                context.report(node, "Expected a space before *.");
+            }
+        }
+
+        // check for function* name() {}
+        if (position === "start") {
+
+            // * begins where the previous identifier ends
+            if (starToken.range[0] !== context.getTokenBefore(starToken).range[1]) {
+                context.report(node, "Expected no space before *.");
+            }
+        }
+
+        // check for function * name() {}
+        if (position === "middle") {
+
+            // must be a space before and afer the *
+            if (starToken.range[0] <= context.getTokenBefore(starToken).range[1] ||
+                starToken.range[1] >= context.getTokenAfter(starToken).range[0]) {
+                context.report(node, "Expected spaces around *.");
+            }
+        }
+    }
+
+    return {
+        "FunctionDeclaration": checkStarPosition,
+        "FunctionExpression": checkStarPosition
+    };
+
+};