Combine sorter spec with projection

packages/minimongo/package.js

@@ -28,7 +28,8 @@ Package.on_use(function (api) {
   // Functionality used only by oplog tailing on the server side
   api.add_files([
     'selector_projection.js',
-    'selector_modifier.js'
+    'selector_modifier.js',
+    'sorter_projection.js'
   ], 'server');
 });
 

packages/minimongo/selector_projection.js

@@ -12,12 +12,23 @@ Minimongo.Matcher.prototype.combineIntoProjection = function (projection) {
   if (_.contains(selectorPaths, ''))
     return {};
 
+  return combineImportantPathsIntoProjection(selectorPaths, projection);
+};
+
+Minimongo.Matcher.prototype._getPathsElidingNumericKeys = function () {
+  var self = this;
+  return _.map(self._getPaths(), function (path) {
+    return _.reject(path.split('.'), isNumericKey).join('.');
+  });
+};
+
+combineImportantPathsIntoProjection = function (paths, projection) {
   var prjDetails = projectionDetails(projection);
   var tree = prjDetails.tree;
   var mergedProjection = {};
 
   // merge the paths to include
-  tree = pathsToTree(selectorPaths,
+  tree = pathsToTree(paths,
                      function (path) { return true; },
                      function (node, path, fullPath) { return true; },
                      tree);
@@ -40,13 +51,6 @@ Minimongo.Matcher.prototype.combineIntoProjection = function (projection) {
   }
 };
 
-Minimongo.Matcher.prototype._getPathsElidingNumericKeys = function () {
-  var self = this;
-  return _.map(self._getPaths(), function (path) {
-    return _.reject(path.split('.'), isNumericKey).join('.');
-  });
-};
-
 // Returns a set of key paths similar to
 // { 'foo.bar': 1, 'a.b.c': 1 }
 var treeToPaths = function (tree, prefix) {

packages/minimongo/sort.js

@@ -38,7 +38,7 @@ Sorter = function (spec) {
       });
     }
   } else {
-    throw Error("Bad sort specification: ", JSON.stringify(spec));
+    throw Error("Bad sort specification: " + JSON.stringify(spec));
   }
 
   // reduceValue takes in all the possible values for the sort key along various

packages/minimongo/sorter_projection.js

@@ -0,0 +1,19 @@
+Sorter.combineSpecIntoProjection = function (spec, projection) {
+  var self = this;
+  var specPaths = getSortSpecPaths(spec);
+
+  return combineImportantPathsIntoProjection(specPaths, projection);
+};
+
+var getSortSpecPaths = function (spec) {
+  if (_.isArray(spec))
+    return _.map(spec, function (fieldSpec) {
+      return _.isArray(fieldSpec) ? fieldSpec[0] : fieldSpec;
+    });
+
+  if (_.isObject(spec))
+    return _.keys(spec);
+
+  throw new Error("Bad sort specification: " + JSON.stringify(spec));
+};
+