diff options
Diffstat (limited to 'tools/eslint/lib/rules/no-unmodified-loop-condition.js')
| -rw-r--r-- | tools/eslint/lib/rules/no-unmodified-loop-condition.js | 68 |
1 files changed, 45 insertions, 23 deletions
diff --git a/tools/eslint/lib/rules/no-unmodified-loop-condition.js b/tools/eslint/lib/rules/no-unmodified-loop-condition.js index f66e7aa755..47a0e3885a 100644 --- a/tools/eslint/lib/rules/no-unmodified-loop-condition.js +++ b/tools/eslint/lib/rules/no-unmodified-loop-condition.js @@ -12,7 +12,7 @@ //------------------------------------------------------------------------------ var Map = require("es6-map"), - estraverse = require("../util/estraverse"), + Traverser = require("../util/traverser"), astUtils = require("../ast-utils"); //------------------------------------------------------------------------------ @@ -29,8 +29,8 @@ var DYNAMIC_PATTERN = /^(?:Call|Member|New|TaggedTemplate|Yield)Expression$/; /** * @typedef {object} LoopConditionInfo * @property {escope.Reference} reference - The reference. - * @property {ASTNode[]} groups - BinaryExpression or ConditionalExpression - * nodes that the reference is belonging to. + * @property {ASTNode} group - BinaryExpression or ConditionalExpression nodes + * that the reference is belonging to. * @property {function} isInLoop - The predicate which checks a given reference * is in this loop. * @property {boolean} modified - The flag that the reference is modified in @@ -46,6 +46,7 @@ var DYNAMIC_PATTERN = /^(?:Call|Member|New|TaggedTemplate|Yield)Expression$/; function isWriteReference(reference) { if (reference.init) { var def = reference.resolved && reference.resolved.defs[0]; + if (!def || def.type !== "Variable" || def.parent.kind !== "var") { return false; } @@ -66,13 +67,13 @@ function isUnmodified(condition) { /** * Checks whether or not a given loop condition info does not have the modified - * flag and does not have any groups that this condition is belonging to. + * 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.groups.length === 0; + return !(condition.modified || condition.group); } /** @@ -85,6 +86,7 @@ function isUnmodifiedAndNotBelongToGroup(condition) { function isInRange(node, reference) { var or = node.range; var ir = reference.identifier.range; + return or[0] <= ir[0] && ir[1] <= or[1]; } @@ -115,9 +117,10 @@ var isInLoop = { * @returns {boolean} `true` if the node is dynamic. */ function hasDynamicExpressions(root) { - var retv = false; + var retv = false, + traverser = new Traverser(); - estraverse.traverse(root, { + traverser.traverse(root, { enter: function(node) { if (DYNAMIC_PATTERN.test(node.type)) { retv = true; @@ -142,32 +145,38 @@ function toLoopCondition(reference) { return null; } - var groups = []; + var group = null; var child = reference.identifier; var 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: reference, - groups: groups, + group: 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 that the reference is belonging to. + /* + * 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)) { - // This expression is dynamic, so don't check. break; } else { - groups.push(node); + group = node; } } @@ -213,9 +222,16 @@ function updateModifiedFlag(conditions, modifiers) { var condition = conditions[i]; for (var j = 0; !condition.modified && j < modifiers.length; ++j) { - var modifier = modifiers[j]; - var inLoop = condition.isInLoop(modifier) || Boolean( - // Checks the function that this modifier is belonging to is used in the loop. + var modifier = modifiers[j], + inLoop; + + /* + * 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. + */ + inLoop = condition.isInLoop(modifier) || Boolean( (funcNode = getEncloseFunctionDeclaration(modifier)) && (funcVar = astUtils.getVariableByName(modifier.from.upper, funcNode.id.name)) && funcVar.references.some(condition.isInLoop) @@ -249,7 +265,7 @@ module.exports = function(context) { } /** - * Registers given conditions to groups that the condition is belonging to. + * Registers given conditions to the group the condition belongs to. * * @param {LoopConditionInfo[]} conditions - A loop condition info to * register. @@ -259,12 +275,12 @@ module.exports = function(context) { for (var i = 0; i < conditions.length; ++i) { var condition = conditions[i]; - for (var j = 0; j < condition.groups.length; ++j) { - var be = condition.groups[j]; - var group = groupMap.get(be); + if (condition.group) { + var group = groupMap.get(condition.group); + if (!group) { group = []; - groupMap.set(be, group); + groupMap.set(condition.group, group); } group.push(condition); } @@ -291,6 +307,7 @@ module.exports = function(context) { * @returns {void} */ function checkReferences(variable) { + // Gets references that exist in loop conditions. var conditions = variable .references @@ -306,12 +323,15 @@ module.exports = function(context) { // Check the conditions are modified. var 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. + /* + * Reports the conditions which are not belonging to groups. + * Others will be reported after all variables are done. + */ conditions .filter(isUnmodifiedAndNotBelongToGroup) .forEach(report); @@ -320,9 +340,11 @@ module.exports = function(context) { return { "Program:exit": function() { var queue = [context.getScope()]; + groupMap = new Map(); var scope; + while ((scope = queue.pop())) { pushAll(queue, scope.childScopes); scope.variables.forEach(checkReferences); |