From 1f0d19ac1894fc858fd45505e9cea5bc01230a12 Mon Sep 17 00:00:00 2001
From: Louis Chatriot <louis.chatriot@gmail.com>
Date: Thu, 30 May 2013 14:19:17 +0200
Subject: [PATCH] No side effect when using multiple indexes

---
 lib/datastore.js | 26 ++++++++++++++++++++++----
 test/db.test.js  | 30 +++++++++++++++++++++++++++---
 2 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/lib/datastore.js b/lib/datastore.js
index 0b6b4d4..d536fa8 100644
--- a/lib/datastore.js
+++ b/lib/datastore.js
@@ -65,11 +65,29 @@ Datastore.prototype.ensureIndex = function (options) {
  * Add one or several document(s) to all indexes
  */
 Datastore.prototype.addToIndexes = function (doc) {
-  var self = this;
+  var self = this
+    , i, failingIndex, error
+    , keys = Object.keys(this.indexes)
+    ;
 
-  Object.keys(this.indexes).forEach(function (i) {
-    self.indexes[i].insert(doc);
-  });
+  for (i = 0; i < keys.length; i += 1) {
+    try {
+      this.indexes[keys[i]].insert(doc);
+    } catch (e) {
+      failingIndex = i;
+      error = e;
+      break;
+    }
+  }
+
+  // If an error happened, we need to rollback the insert on all other indexes
+  if (error) {
+    for (i = 0; i < failingIndex; i += 1) {
+      this.indexes[keys[i]].remove(doc);
+    }
+
+    throw error;
+  }
 };
 
 
diff --git a/test/db.test.js b/test/db.test.js
index 9d357f1..073549d 100644
--- a/test/db.test.js
+++ b/test/db.test.js
@@ -1288,7 +1288,7 @@ describe('Database', function () {
         });
       });
 
-      it('If the index has a unique constraint, an error is thrown if it is violated', function (done) {
+      it('If the index has a unique constraint, an error is thrown if it is violated and the data didnt change', function (done) {
         d.ensureIndex({ fieldName: 'z', unique: true });
         d.indexes.z.tree.getNumberOfKeys().should.equal(0);
 
@@ -1316,8 +1316,32 @@ describe('Database', function () {
         });
       });
 
-      it.skip('If the index has a unique constraint, others cannot be modified when it raises an error', function (done) {
-        done();
+      it('If the index has a unique constraint, others cannot be modified when it raises an error', function (done) {
+        d.ensureIndex({ fieldName: 'nonu1' });
+        d.ensureIndex({ fieldName: 'uni', unique: true });
+        d.ensureIndex({ fieldName: 'nonu2' });
+
+        d.insert({ nonu1: 'yes', nonu2: 'yes2', uni: 'willfail' }, function (err, newDoc) {
+          assert.isNull(err);
+          d.indexes.nonu1.tree.getNumberOfKeys().should.equal(1);
+          d.indexes.uni.tree.getNumberOfKeys().should.equal(1);
+          d.indexes.nonu2.tree.getNumberOfKeys().should.equal(1);
+
+          d.insert({ nonu1: 'no', nonu2: 'no2', uni: 'willfail' }, function (err) {
+            err.errorType.should.equal('uniqueViolated');
+
+            // No index was modified
+            d.indexes.nonu1.tree.getNumberOfKeys().should.equal(1);
+            d.indexes.uni.tree.getNumberOfKeys().should.equal(1);
+            d.indexes.nonu2.tree.getNumberOfKeys().should.equal(1);
+
+            assert.deepEqual(d.indexes.nonu1.getMatching('yes'), [newDoc]);
+            assert.deepEqual(d.indexes.uni.getMatching('willfail'), [newDoc]);
+            assert.deepEqual(d.indexes.nonu2.getMatching('yes2'), [newDoc]);
+
+            done();
+          });
+        });
       });
 
     });   // ==== End of 'Indexing newly inserted documents' ==== //