Allow partial list of ids for sortByIds

lib/dao.js

@@ -351,19 +351,29 @@ DataAccessObject.sortByIds = function(ids, results) {
       return (typeof id === 'object') ? id.toString() : id;
   });
   
-  results.sort(function(x, y) {
-    var idA = (typeof x[pk] === 'object') ? x[pk].toString() : x[pk];
-    var idB = (typeof y[pk] === 'object') ? y[pk].toString() : y[pk];
-    var a = ids.indexOf(idA);
-    var b = ids.indexOf(idB);
-    if (a === -1 || b === -1) return 1; // last
-    if (a !== b) {
-      if (a > b) return 1;
-      if (a < b) return -1;
-    }
+  var indexOf = function(x) {
+    var id = (typeof x[pk] === 'object') ? x[pk].toString() : x[pk];
+    return ids.indexOf(id);
+  };
+  
+  var heading = [];
+  var tailing = [];
+  
+  results.forEach(function(x) {
+    var idx = indexOf(x);
+    idx === -1 ? tailing.push(x) : heading.push(x);
   });
   
-  return results;
+  heading.sort(function(x, y) {
+    var a = indexOf(x);
+    var b = indexOf(y);
+    if (a === -1 || b === -1) return 1; // last
+    if (a === b) return 0;
+    if (a > b) return 1;
+    if (a < b) return -1;
+  });
+  
+  return heading.concat(tailing);
 };
 
 function convertNullToNotFoundError(ctx, cb) {

test/basic-querying.test.js

@@ -87,6 +87,33 @@ describe('basic-querying', function () {
         done();
       });
     });
+    
+    it('should sortByIds', function(done) {
+      User.find(function(err, users) {
+        sorted = User.sortByIds([6, 5, 4, 3, 2, 1], users);
+        var names = sorted.map(function(u) { return u.name; });
+        names.should.eql(['f', 'e', 'd', 'c', 'b', 'a']);
+        done();
+      });
+    });
+    
+    it('should sortByIds - partial ids (1)', function(done) {
+      User.find(function(err, users) {
+        sorted = User.sortByIds([6, 5, 4], users);
+        var names = sorted.map(function(u) { return u.name; });
+        names.should.eql(['f', 'e', 'd', 'a', 'b', 'c']);
+        done();
+      });
+    });
+    
+    it('should sortByIds - partial ids (2)', function(done) {
+      User.find(function(err, users) {
+        sorted = User.sortByIds([5, 3, 2], users);
+        var names = sorted.map(function(u) { return u.name; });
+        names.should.eql(['e', 'c', 'b', 'a', 'd', 'f']);
+        done();
+      });
+    });
 
   });