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diff --git a/tools/node_modules/eslint/lib/rules/no-unmodified-loop-condition.js b/tools/node_modules/eslint/lib/rules/no-unmodified-loop-condition.js
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+++ b/tools/node_modules/eslint/lib/rules/no-unmodified-loop-condition.js
@@ -0,0 +1,366 @@
+/**
+ * @fileoverview Rule to disallow use of unmodified expressions in loop conditions
+ * @author Toru Nagashima
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const Traverser = require("../util/traverser"),
+    astUtils = require("../ast-utils");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+const pushAll = Function.apply.bind(Array.prototype.push);
+const SENTINEL_PATTERN = /(?:(?:Call|Class|Function|Member|New|Yield)Expression|Statement|Declaration)$/;
+const LOOP_PATTERN = /^(?:DoWhile|For|While)Statement$/; // for-in/of statements don't have `test` property.
+const GROUP_PATTERN = /^(?:BinaryExpression|ConditionalExpression)$/;
+const SKIP_PATTERN = /^(?:ArrowFunction|Class|Function)Expression$/;
+const DYNAMIC_PATTERN = /^(?:Call|Member|New|TaggedTemplate|Yield)Expression$/;
+
+/**
+ * @typedef {Object} LoopConditionInfo
+ * @property {eslint-scope.Reference} reference - The reference.
+ * @property {ASTNode} group - BinaryExpression or ConditionalExpression nodes
+ *      that the reference is belonging to.
+ * @property {Function} isInLoop - The predicate which checks a given reference
+ *      is in this loop.
+ * @property {boolean} modified - The flag that the reference is modified in
+ *      this loop.
+ */
+
+/**
+ * Checks whether or not a given reference is a write reference.
+ *
+ * @param {eslint-scope.Reference} reference - A reference to check.
+ * @returns {boolean} `true` if the reference is a write reference.
+ */
+function isWriteReference(reference) {
+    if (reference.init) {
+        const def = reference.resolved && reference.resolved.defs[0];
+
+        if (!def || def.type !== "Variable" || def.parent.kind !== "var") {
+            return false;
+        }
+    }
+    return reference.isWrite();
+}
+
+/**
+ * Checks whether or not a given loop condition info does not have the modified
+ * flag.
+ *
+ * @param {LoopConditionInfo} condition - A loop condition info to check.
+ * @returns {boolean} `true` if the loop condition info is "unmodified".
+ */
+function isUnmodified(condition) {
+    return !condition.modified;
+}
+
+/**
+ * Checks whether or not a given loop condition info does not have the modified
+ * flag and does not have the group this condition belongs to.
+ *
+ * @param {LoopConditionInfo} condition - A loop condition info to check.
+ * @returns {boolean} `true` if the loop condition info is "unmodified".
+ */
+function isUnmodifiedAndNotBelongToGroup(condition) {
+    return !(condition.modified || condition.group);
+}
+
+/**
+ * Checks whether or not a given reference is inside of a given node.
+ *
+ * @param {ASTNode} node - A node to check.
+ * @param {eslint-scope.Reference} reference - A reference to check.
+ * @returns {boolean} `true` if the reference is inside of the node.
+ */
+function isInRange(node, reference) {
+    const or = node.range;
+    const ir = reference.identifier.range;
+
+    return or[0] <= ir[0] && ir[1] <= or[1];
+}
+
+/**
+ * Checks whether or not a given reference is inside of a loop node's condition.
+ *
+ * @param {ASTNode} node - A node to check.
+ * @param {eslint-scope.Reference} reference - A reference to check.
+ * @returns {boolean} `true` if the reference is inside of the loop node's
+ *      condition.
+ */
+const isInLoop = {
+    WhileStatement: isInRange,
+    DoWhileStatement: isInRange,
+    ForStatement(node, reference) {
+        return (
+            isInRange(node, reference) &&
+            !(node.init && isInRange(node.init, reference))
+        );
+    }
+};
+
+/**
+ * Checks whether or not a given group node has any dynamic elements.
+ *
+ * @param {ASTNode} root - A node to check.
+ *      This node is one of BinaryExpression or ConditionalExpression.
+ * @returns {boolean} `true` if the node is dynamic.
+ */
+function hasDynamicExpressions(root) {
+    let retv = false;
+    const traverser = new Traverser();
+
+    traverser.traverse(root, {
+        enter(node) {
+            if (DYNAMIC_PATTERN.test(node.type)) {
+                retv = true;
+                this.break();
+            } else if (SKIP_PATTERN.test(node.type)) {
+                this.skip();
+            }
+        }
+    });
+
+    return retv;
+}
+
+/**
+ * Creates the loop condition information from a given reference.
+ *
+ * @param {eslint-scope.Reference} reference - A reference to create.
+ * @returns {LoopConditionInfo|null} Created loop condition info, or null.
+ */
+function toLoopCondition(reference) {
+    if (reference.init) {
+        return null;
+    }
+
+    let group = null;
+    let child = reference.identifier;
+    let node = child.parent;
+
+    while (node) {
+        if (SENTINEL_PATTERN.test(node.type)) {
+            if (LOOP_PATTERN.test(node.type) && node.test === child) {
+
+                // This reference is inside of a loop condition.
+                return {
+                    reference,
+                    group,
+                    isInLoop: isInLoop[node.type].bind(null, node),
+                    modified: false
+                };
+            }
+
+            // This reference is outside of a loop condition.
+            break;
+        }
+
+        /*
+         * If it's inside of a group, OK if either operand is modified.
+         * So stores the group this reference belongs to.
+         */
+        if (GROUP_PATTERN.test(node.type)) {
+
+            // If this expression is dynamic, no need to check.
+            if (hasDynamicExpressions(node)) {
+                break;
+            } else {
+                group = node;
+            }
+        }
+
+        child = node;
+        node = node.parent;
+    }
+
+    return null;
+}
+
+/**
+ * Gets the function which encloses a given reference.
+ * This supports only FunctionDeclaration.
+ *
+ * @param {eslint-scope.Reference} reference - A reference to get.
+ * @returns {ASTNode|null} The function node or null.
+ */
+function getEncloseFunctionDeclaration(reference) {
+    let node = reference.identifier;
+
+    while (node) {
+        if (node.type === "FunctionDeclaration") {
+            return node.id ? node : null;
+        }
+
+        node = node.parent;
+    }
+
+    return null;
+}
+
+/**
+ * Updates the "modified" flags of given loop conditions with given modifiers.
+ *
+ * @param {LoopConditionInfo[]} conditions - The loop conditions to be updated.
+ * @param {eslint-scope.Reference[]} modifiers - The references to update.
+ * @returns {void}
+ */
+function updateModifiedFlag(conditions, modifiers) {
+
+    for (let i = 0; i < conditions.length; ++i) {
+        const condition = conditions[i];
+
+        for (let j = 0; !condition.modified && j < modifiers.length; ++j) {
+            const modifier = modifiers[j];
+            let funcNode, funcVar;
+
+            /*
+             * Besides checking for the condition being in the loop, we want to
+             * check the function that this modifier is belonging to is called
+             * in the loop.
+             * FIXME: This should probably be extracted to a function.
+             */
+            const inLoop = condition.isInLoop(modifier) || Boolean(
+                (funcNode = getEncloseFunctionDeclaration(modifier)) &&
+                (funcVar = astUtils.getVariableByName(modifier.from.upper, funcNode.id.name)) &&
+                funcVar.references.some(condition.isInLoop)
+            );
+
+            condition.modified = inLoop;
+        }
+    }
+}
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = {
+    meta: {
+        docs: {
+            description: "disallow unmodified loop conditions",
+            category: "Best Practices",
+            recommended: false
+        },
+
+        schema: []
+    },
+
+    create(context) {
+        let groupMap = null;
+
+        /**
+         * Reports a given condition info.
+         *
+         * @param {LoopConditionInfo} condition - A loop condition info to report.
+         * @returns {void}
+         */
+        function report(condition) {
+            const node = condition.reference.identifier;
+
+            context.report({
+                node,
+                message: "'{{name}}' is not modified in this loop.",
+                data: node
+            });
+        }
+
+        /**
+         * Registers given conditions to the group the condition belongs to.
+         *
+         * @param {LoopConditionInfo[]} conditions - A loop condition info to
+         *      register.
+         * @returns {void}
+         */
+        function registerConditionsToGroup(conditions) {
+            for (let i = 0; i < conditions.length; ++i) {
+                const condition = conditions[i];
+
+                if (condition.group) {
+                    let group = groupMap.get(condition.group);
+
+                    if (!group) {
+                        group = [];
+                        groupMap.set(condition.group, group);
+                    }
+                    group.push(condition);
+                }
+            }
+        }
+
+        /**
+         * Reports references which are inside of unmodified groups.
+         *
+         * @param {LoopConditionInfo[]} conditions - A loop condition info to report.
+         * @returns {void}
+         */
+        function checkConditionsInGroup(conditions) {
+            if (conditions.every(isUnmodified)) {
+                conditions.forEach(report);
+            }
+        }
+
+        /**
+         * Finds unmodified references which are inside of a loop condition.
+         * Then reports the references which are outside of groups.
+         *
+         * @param {eslint-scope.Variable} variable - A variable to report.
+         * @returns {void}
+         */
+        function checkReferences(variable) {
+
+            // Gets references that exist in loop conditions.
+            const conditions = variable
+                .references
+                .map(toLoopCondition)
+                .filter(Boolean);
+
+            if (conditions.length === 0) {
+                return;
+            }
+
+            // Registers the conditions to belonging groups.
+            registerConditionsToGroup(conditions);
+
+            // Check the conditions are modified.
+            const modifiers = variable.references.filter(isWriteReference);
+
+            if (modifiers.length > 0) {
+                updateModifiedFlag(conditions, modifiers);
+            }
+
+            /*
+             * Reports the conditions which are not belonging to groups.
+             * Others will be reported after all variables are done.
+             */
+            conditions
+                .filter(isUnmodifiedAndNotBelongToGroup)
+                .forEach(report);
+        }
+
+        return {
+            "Program:exit"() {
+                const queue = [context.getScope()];
+
+                groupMap = new Map();
+
+                let scope;
+
+                while ((scope = queue.pop())) {
+                    pushAll(queue, scope.childScopes);
+                    scope.variables.forEach(checkReferences);
+                }
+
+                groupMap.forEach(checkConditionsInGroup);
+                groupMap = null;
+            }
+        };
+    }
+};