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diff --git a/tools/eslint/lib/rules/comma-style.js b/tools/eslint/lib/rules/comma-style.js
new file mode 100644
index 0000000000..4b8d145775
--- /dev/null
+++ b/tools/eslint/lib/rules/comma-style.js
@@ -0,0 +1,177 @@
+/**
+ * @fileoverview Comma style - enforces comma styles of two types: last and first
+ * @author Vignesh Anand aka vegetableman
+ * @copyright 2014 Vignesh Anand. All rights reserved.
+ * @copyright 2015 Evan Simmons. All rights reserved.
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function(context) {
+
+    var style = context.options[0] || "last",
+        exceptions = {};
+
+    if (context.options.length === 2 && context.options[1].hasOwnProperty("exceptions")) {
+        exceptions = context.options[1].exceptions;
+    }
+
+    //--------------------------------------------------------------------------
+    // Helpers
+    //--------------------------------------------------------------------------
+
+    /**
+     * Checks whether two tokens are on the same line.
+     * @param {ASTNode} left The leftmost token.
+     * @param {ASTNode} right The rightmost token.
+     * @returns {boolean} True if the tokens are on the same line, false if not.
+     * @private
+     */
+    function isSameLine(left, right) {
+        return left.loc.end.line === right.loc.start.line;
+    }
+
+    /**
+     * Determines if a given token is a comma operator.
+     * @param {ASTNode} token The token to check.
+     * @returns {boolean} True if the token is a comma, false if not.
+     * @private
+     */
+    function isComma(token) {
+        return !!token && (token.type === "Punctuator") && (token.value === ",");
+    }
+
+    /**
+     * Validates the spacing around single items in lists.
+     * @param {Token} previousItemToken The last token from the previous item.
+     * @param {Token} commaToken The token representing the comma.
+     * @param {Token} currentItemToken The first token of the current item.
+     * @param {Token} reportItem The item to use when reporting an error.
+     * @returns {void}
+     * @private
+     */
+    function validateCommaItemSpacing(previousItemToken, commaToken, currentItemToken, reportItem) {
+
+        // if single line
+        if (isSameLine(commaToken, currentItemToken) &&
+                isSameLine(previousItemToken, commaToken)) {
+
+            return;
+
+        } else if (!isSameLine(commaToken, currentItemToken) &&
+                !isSameLine(previousItemToken, commaToken)) {
+
+            // lone comma
+            context.report(reportItem, {
+                line: commaToken.loc.end.line,
+                column: commaToken.loc.start.column
+            }, "Bad line breaking before and after ','.");
+
+        } else if (style === "first" && !isSameLine(commaToken, currentItemToken)) {
+
+            context.report(reportItem, "',' should be placed first.");
+
+        } else if (style === "last" && isSameLine(commaToken, currentItemToken)) {
+
+            context.report(reportItem, {
+                line: commaToken.loc.end.line,
+                column: commaToken.loc.end.column
+            }, "',' should be placed last.");
+        }
+    }
+
+    /**
+     * Checks the comma placement with regards to a declaration/property/element
+     * @param {ASTNode} node The binary expression node to check
+     * @param {string} property The property of the node containing child nodes.
+     * @private
+     * @returns {void}
+     */
+    function validateComma(node, property) {
+        var items = node[property],
+            arrayLiteral = (node.type === "ArrayExpression"),
+            previousItemToken;
+
+        if (items.length > 1 || arrayLiteral) {
+
+            // seed as opening [
+            previousItemToken = context.getFirstToken(node);
+
+            items.forEach(function(item) {
+                var commaToken = item ? context.getTokenBefore(item) : previousItemToken,
+                    currentItemToken = item ? context.getFirstToken(item) : context.getTokenAfter(commaToken),
+                    reportItem = item || currentItemToken;
+
+                /*
+                 * This works by comparing three token locations:
+                 * - previousItemToken is the last token of the previous item
+                 * - commaToken is the location of the comma before the current item
+                 * - currentItemToken is the first token of the current item
+                 *
+                 * These values get switched around if item is undefined.
+                 * previousItemToken will refer to the last token not belonging
+                 * to the current item, which could be a comma or an opening
+                 * square bracket. currentItemToken could be a comma.
+                 *
+                 * All comparisons are done based on these tokens directly, so
+                 * they are always valid regardless of an undefined item.
+                 */
+                if (isComma(commaToken)) {
+                    validateCommaItemSpacing(previousItemToken, commaToken,
+                            currentItemToken, reportItem);
+                }
+
+                previousItemToken = item ? context.getLastToken(item) : previousItemToken;
+            });
+
+            /*
+             * Special case for array literals that have empty last items, such
+             * as [ 1, 2, ]. These arrays only have two items show up in the
+             * AST, so we need to look at the token to verify that there's no
+             * dangling comma.
+             */
+            if (arrayLiteral) {
+
+                var lastToken = context.getLastToken(node),
+                    nextToLastToken = context.getTokenBefore(lastToken);
+
+                if (isComma(nextToLastToken)) {
+                    validateCommaItemSpacing(
+                        context.getTokenBefore(nextToLastToken),
+                        nextToLastToken,
+                        lastToken,
+                        lastToken
+                    );
+                }
+            }
+        }
+    }
+
+    //--------------------------------------------------------------------------
+    // Public
+    //--------------------------------------------------------------------------
+
+    var nodes = {};
+
+    if (!exceptions.VariableDeclaration) {
+        nodes.VariableDeclaration = function(node) {
+            validateComma(node, "declarations");
+        };
+    }
+    if (!exceptions.ObjectExpression) {
+        nodes.ObjectExpression = function(node) {
+            validateComma(node, "properties");
+        };
+    }
+    if (!exceptions.ArrayExpression) {
+        nodes.ArrayExpression = function(node) {
+            validateComma(node, "elements");
+        };
+    }
+
+    return nodes;
+};