From 2dc25d77aed7b759ebf76a2e1adbac300f936577 Mon Sep 17 00:00:00 2001
From: Slava Kim <slava@meteor.com>
Date: Wed, 9 Oct 2013 15:02:02 -0700
Subject: [PATCH] Fix prefix check. Remove all numeric keys from sel

---
 packages/minimongo/minimongo_tests.js | 12 ++++++++++++
 packages/minimongo/selector.js        | 11 ++++++++---
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/packages/minimongo/minimongo_tests.js b/packages/minimongo/minimongo_tests.js
index 8288bc8baa..1899f87501 100644
--- a/packages/minimongo/minimongo_tests.js
+++ b/packages/minimongo/minimongo_tests.js
@@ -2433,5 +2433,17 @@ Tinytest.add("minimongo - modifier affects selector", function (test) {
   notAffected({ 'foo.bar': 0 }, { $set: { 'foo.baz': 1 } }, "simplest");
   affected({ 'foo.bar': 0 }, { $set: { 'foo.1': 1 } }, "simplest");
   affected({ 'foo.bar': 0 }, { $set: { 'foo.2.bar': 1 } }, "simplest");
+
+  notAffected({ 'foo': 0 }, { $set: { 'foobaz': 1 } }, "correct prefix check");
+  notAffected({ 'foobar': 0 }, { $unset: { 'foo': 1 } }, "correct prefix check");
+  notAffected({ 'foo.bar': 0 }, { $unset: { 'foob': 1 } }, "correct prefix check");
+
+  // XXX once we consider all the array/non-array operators separately, this
+  // should become notAffected. Until then it's fine to let it "match" and
+  // affect.
+  //notAffected({ 'foo.3.bar': 0 }, { $set: { 'foo.2.bar': 1 } }, "observe for an array element");
+  affected({ 'foo.3.bar': 0 }, { $set: { 'foo.2.bar': 1 } }, "observe for an array element");
+
+  affected({ 'foo.3.bar': 0 }, { $set: { 'foo.3.bar': 1 } }, "observe for an array element");
 });
 
diff --git a/packages/minimongo/selector.js b/packages/minimongo/selector.js
index a49385127b..b37b2cd2e7 100644
--- a/packages/minimongo/selector.js
+++ b/packages/minimongo/selector.js
@@ -802,9 +802,9 @@ LocalCollection._isSelectorAffectedByModifier = function (selector, modifier) {
   return _.any(modifiedPaths, function (path) {
     path = removeNumericsKeys(path);
     return _.any(meaningfulPaths, function (meaningfulPath) {
-      // It's full prefix
-      return path.indexOf(meaningfulPath) === 0
-          || meaningfulPath.indexOf(path) === 0;
+      meaningfulPath = removeNumericsKeys(meaningfulPath);
+      return isPathPrefix(path, meaningfulPath)
+          || isPathPrefix(meaningfulPath, path);
     });
   });
 
@@ -812,6 +812,11 @@ LocalCollection._isSelectorAffectedByModifier = function (selector, modifier) {
     return _.filter(path.split('.'), isNaN).join('.');
   }
 
+  function isPathPrefix (s, t) {
+    var pos = t.indexOf(s);
+    return pos === 0
+        && (pos + s.length === t.length || t[pos + s.length] === '.');
+  }
 };
 
 // Returns a list of key paths the given selector is looking for