1 files changed, 94 insertions, 0 deletions
diff --git a/tools/eslint/lib/rules/space-infix-ops.js b/tools/eslint/lib/rules/space-infix-ops.js
new file mode 100644
index 0000000000..a3f3c940ac
--- /dev/null
+++ b/tools/eslint/lib/rules/space-infix-ops.js
@@ -0,0 +1,94 @@
+/**
+ * @fileoverview Require spaces around infix operators
+ * @author Michael Ficarra
+ */
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function(context) {
+    var int32Hint = context.options[0] ? context.options[0].int32Hint === true : false;
+
+    var OPERATORS = [
+        "*", "/", "%", "+", "-", "<<", ">>", ">>>", "<", "<=", ">", ">=", "in",
+        "instanceof", "==", "!=", "===", "!==", "&", "^", "|", "&&", "||", "=",
+        "+=", "-=", "*=", "/=", "%=", "<<=", ">>=", ">>>=", "&=", "^=", "|=",
+        "?", ":", ","
+    ];
+
+    /**
+     * Returns the first token which violates the rule
+     * @param {ASTNode} left - The left node of the main node
+     * @param {ASTNode} right - The right node of the main node
+     * @returns {object} The violator token or null
+     * @private
+     */
+    function getFirstNonSpacedToken(left, right) {
+        var op, tokens = context.getTokensBetween(left, right, 1);
+        for (var i = 1, l = tokens.length - 1; i < l; ++i) {
+            op = tokens[i];
+            if (
+                op.type === "Punctuator" &&
+                OPERATORS.indexOf(op.value) >= 0 &&
+                (tokens[i - 1].range[1] >= op.range[0] || op.range[1] >= tokens[i + 1].range[0])
+            ) {
+                return op;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Reports an AST node as a rule violation
+     * @param {ASTNode} mainNode - The node to report
+     * @param {object} culpritToken - The token which has a problem
+     * @returns {void}
+     * @private
+     */
+    function report(mainNode, culpritToken) {
+        context.report(mainNode, culpritToken.loc.start, "Infix operators must be spaced.");
+    }
+
+    function checkBinary(node) {
+        var nonSpacedNode = getFirstNonSpacedToken(node.left, node.right);
+
+        if (nonSpacedNode) {
+            if (!(int32Hint && context.getSource(node).substr(-2) === "|0")) {
+                report(node, nonSpacedNode);
+            }
+        }
+    }
+
+    function checkConditional(node) {
+        var nonSpacedConsequesntNode = getFirstNonSpacedToken(node.test, node.consequent);
+        var nonSpacedAlternateNode = getFirstNonSpacedToken(node.consequent, node.alternate);
+
+        if (nonSpacedConsequesntNode) {
+            report(node, nonSpacedConsequesntNode);
+        } else if (nonSpacedAlternateNode) {
+            report(node, nonSpacedAlternateNode);
+        }
+    }
+
+    function checkVar(node) {
+        var nonSpacedNode;
+
+        if (node.init) {
+            nonSpacedNode = getFirstNonSpacedToken(node.id, node.init);
+            if (nonSpacedNode) {
+                report(node, nonSpacedNode);
+            }
+        }
+    }
+
+    return {
+        "AssignmentExpression": checkBinary,
+        "BinaryExpression": checkBinary,
+        "LogicalExpression": checkBinary,
+        "ConditionalExpression": checkConditional,
+        "VariableDeclarator": checkVar
+    };
+
+};