make geo nearFilter support minDistance (#987)

lib/geo.js

@@ -22,6 +22,7 @@ exports.nearFilter = function nearFilter(where) {
         result = {
           near: ex.near,
           maxDistance: ex.maxDistance,
+          minDistance: ex.minDistance,
           unit: ex.unit,
           key: key,
         };
@@ -39,6 +40,7 @@ exports.nearFilter = function nearFilter(where) {
 exports.filter = function(arr, filter) {
   var origin = filter.near;
   var max = filter.maxDistance > 0 ? filter.maxDistance : false;
+  var min = filter.minDistance > 0 ? filter.minDistance : false;
   var unit = filter.unit;
   var key = filter.key;
 
@@ -61,6 +63,9 @@ exports.filter = function(arr, filter) {
 
     var d = GeoPoint.distanceBetween(origin, loc, {type: unit});
 
+    if (min && d < min) {
+      return;
+    }
     if (max && d > max) {
       // dont add
     } else {

test/geo.test.js

@@ -11,6 +11,8 @@
 require('should');
 
 var GeoPoint = require('../lib/geo').GeoPoint;
+var nearFilter = require('../lib/geo').nearFilter;
+var geoFilter = require('../lib/geo').filter;
 var DELTA = 0.0000001;
 
 describe('GeoPoint', function() {
@@ -132,4 +134,70 @@ describe('GeoPoint', function() {
       distance.should.be.approximately(0.0004483676593058972, DELTA);
     });
   });
+
+  describe('nearFilter()', function() {
+    it('should return a filter includes minDistance if where contains minDistance option', function() {
+      var where = {
+        location: {
+          near: {
+            lat: 40.77492964101182,
+            lng: -73.90950187151662,
+          },
+          minDistance: 100,
+        },
+      };
+      var filter = nearFilter(where);
+      filter.key.should.equal('location');
+      filter.should.have.properties({
+        key: 'location',
+        near: {
+          lat: 40.77492964101182,
+          lng: -73.90950187151662,
+        },
+        minDistance: 100,
+      });
+    });
+  });
+
+  describe('filter()', function() {
+    it('should be able to filter geo points via minDistance', function() {
+      var points = [{
+        location: {
+          lat: 30.283552,
+          lng: 120.126048,
+        },
+      }, {
+        location: {
+          lat: 30.380307,
+          lng: 119.979445,
+        },
+      }, {
+        location: {
+          lat: 30.229896,
+          lng: 119.744592,
+        },
+      }, {
+        location: {
+          lat: 30.250863,
+          lng: 120.129498,
+        },
+      }, {
+        location: {
+          lat: 31.244209,
+          lng: 121.483687,
+        },
+      }];
+      var filter = {
+        key: 'location',
+        near: {
+          lat: 30.278562,
+          lng: 120.139846,
+        },
+        unit: 'meters',
+        minDistance: 10000,
+      };
+      var results = geoFilter(points, filter);
+      results.length.should.be.equal(3);
+    });
+  });
 });