fix a bug with the throttling algorithm (#157)

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 4.0.2
+- Fix a bug with the analytics ping throttling algorithm.
+
 ## 4.0.1
 - Force close the http client from `IOAnalytics.close()`.
   This prevents lingering requests from making the application hang.

lib/src/usage_impl.dart

@@ -43,10 +43,10 @@ class ThrottlingBucket {
   }
 
   void _checkReplenish() {
-    var now = DateTime.now().millisecondsSinceEpoch;
+    final now = DateTime.now().millisecondsSinceEpoch;
 
-    if (_lastReplenish + 1000 >= now) {
-      var inc = (now - _lastReplenish) ~/ 1000;
+    if (_lastReplenish + 1000 < now) {
+      final inc = (now - _lastReplenish) ~/ 1000;
       drops = math.min(drops + inc, startingCount);
       _lastReplenish += (1000 * inc);
     }

pubspec.yaml

@@ -3,7 +3,7 @@
 # BSD-style license that can be found in the LICENSE file.
 
 name: usage
-version: 4.0.1
+version: 4.0.2
 description: A Google Analytics wrapper for command-line, web, and Flutter apps.
 homepage: https://github.com/dart-lang/usage
 
@@ -15,4 +15,4 @@ dependencies:
 
 dev_dependencies:
   pedantic: ^1.9.0
-  test: ^1.16.0-nullsafety
+  test: ^1.16.0

test/usage_impl_test.dart

@@ -25,6 +25,18 @@ void defineTests() {
       }
       expect(bucket.removeDrop(), false);
     });
+
+    test('does re-send after throttling', () async {
+      var bucket = ThrottlingBucket(20);
+      for (var i = 0; i < 20; i++) {
+        expect(bucket.removeDrop(), true);
+      }
+      expect(bucket.removeDrop(), false);
+
+      // TODO: Re-write to use package:fake_async.
+      await Future.delayed(Duration(milliseconds: 1500));
+      expect(bucket.removeDrop(), true);
+    });
   });
 
   group('AnalyticsImpl', () {