Merge branch 'master' of github.com:mapbox/node-mbtiles

.gitignore

@@ -0,0 +1,2 @@
+node_modules
+test/fixtures/non_existent.mbtiles

lib/mbtiles.js

@@ -240,8 +240,8 @@ MBTiles.prototype.grid = function(x, y, z, callback) {
             );
         },
         function(err, row, rows) {
+            if ((!row || !row.grid) || (err && err.errno == 1)) return callback('Grid does not exist');
             if (err) return callback(err);
-            if (!row || !row.grid) return callback('Grid does not exist');
 
             try {
                 var grid = zlib.inflate(
@@ -253,10 +253,11 @@ MBTiles.prototype.grid = function(x, y, z, callback) {
                         memo[r.key_name] = JSON.parse(r.key_json);
                         return memo;
                     }, {});
-                callback(null, _(JSON.parse(grid)).extend({ data: data }));
             } catch (err) {
-                callback('Grid is invalid');
+                return callback('Grid is invalid');
             }
+
+            callback(null, _(JSON.parse(grid)).extend({ data: data }));
         }
     );
 };