From bb57fcbe110a8ced8603f690ea92dd1d0203d8d7 Mon Sep 17 00:00:00 2001
From: Raymond Feng <raymond@strongloop.com>
Date: Tue, 10 Jun 2014 16:11:50 -0700
Subject: [PATCH] Fix the comparison for null/boolean values

---
 lib/connectors/memory.js    | 10 +++++++---
 lib/dao.js                  |  8 ++++++--
 test/basic-querying.test.js | 27 +++++++++++++++++++++++++++
 3 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/lib/connectors/memory.js b/lib/connectors/memory.js
index 0b7a36cd..ab54f959 100644
--- a/lib/connectors/memory.js
+++ b/lib/connectors/memory.js
@@ -402,21 +402,25 @@ function applyFilter(filter) {
    * @private
    */
   function compare(val1, val2) {
+    if(val1 == null || val2 == null) {
+      // Either val1 or val2 is null or undefined
+      return val1 == val2 ? 0 : NaN;
+    }
     if (typeof val1 === 'number') {
       return val1 - val2;
     }
     if (typeof val1 === 'string') {
-      return (val1 > val2) ? 1 : ((val1 < val2) ? -1 : 0);
+      return (val1 > val2) ? 1 : ((val1 < val2) ? -1 : (val1 == val2) ? 0 : NaN);
     }
     if (typeof val1 === 'boolean') {
       return val1 - val2;
     }
     if (val1 instanceof Date) {
-      var result = val1.getTime() - ((val2 && val2.getTime()) || 0);
+      var result = val1 - val2;
       return result;
     }
     // Return NaN if we don't know how to compare
-    return (val1 === val2) ? 0 : NaN;
+    return (val1 == val2) ? 0 : NaN;
   }
 
   function testInEquality(example, val) {
diff --git a/lib/dao.js b/lib/dao.js
index f5a6886f..d4bd40de 100644
--- a/lib/dao.js
+++ b/lib/dao.js
@@ -551,10 +551,14 @@ DataAccessObject._coerce = function (where) {
     // Coerce the array items
     if (Array.isArray(val)) {
       for (var i = 0; i < val.length; i++) {
-        val[i] = DataType(val[i]);
+        if (val[i] !== null && val[i] !== undefined) {
+          val[i] = DataType(val[i]);
+        }
       }
     } else {
-      val = DataType(val);
+      if (val !== null && val !== undefined) {
+        val = DataType(val);
+      }
     }
     // Rebuild {property: {operator: value}}
     if (operator) {
diff --git a/test/basic-querying.test.js b/test/basic-querying.test.js
index ef0bfb7f..eaccb348 100644
--- a/test/basic-querying.test.js
+++ b/test/basic-querying.test.js
@@ -256,6 +256,33 @@ describe('basic-querying', function () {
       });
     });
 
+    it('should support number "gt" that is satisfied by null value', function (done) {
+      User.find({order: 'seq', where: { order: { "gt": null }
+      }}, function (err, users) {
+        should.not.exist(err);
+        users.should.have.property('length', 0);
+        done();
+      });
+    });
+
+    it('should support number "lt" that is not satisfied by null value', function (done) {
+      User.find({order: 'seq', where: { order: { "lt": null }
+      }}, function (err, users) {
+        should.not.exist(err);
+        users.should.have.property('length', 0);
+        done();
+      });
+    });
+
+    it('should support string "gte" that is satisfied by null value', function (done) {
+      User.find({order: 'seq', where: { name: { "gte":  null}
+      }}, function (err, users) {
+        should.not.exist(err);
+        users.should.have.property('length', 0);
+        done();
+      });
+    });
+
     it('should support string "gte" that is satisfied', function (done) {
       User.find({order: 'seq', where: { name: { "gte":  'Paul McCartney'}
       }}, function (err, users) {