1 files changed, 114 insertions, 0 deletions
diff --git a/mfbt/tests/TestRollingMean.cpp b/mfbt/tests/TestRollingMean.cpp
new file mode 100644
index 0000000000..001d827c4f
--- /dev/null
+++ b/mfbt/tests/TestRollingMean.cpp
@@ -0,0 +1,114 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Assertions.h"
+#include "mozilla/RollingMean.h"
+
+using mozilla::RollingMean;
+
+class MyClass {
+ public:
+  uint32_t mValue;
+
+  explicit MyClass(uint32_t aValue = 0) : mValue(aValue) {}
+
+  bool operator==(const MyClass& aOther) const {
+    return mValue == aOther.mValue;
+  }
+
+  MyClass operator+(const MyClass& aOther) const {
+    return MyClass(mValue + aOther.mValue);
+  }
+
+  MyClass operator-(const MyClass& aOther) const {
+    return MyClass(mValue - aOther.mValue);
+  }
+
+  MyClass operator/(uint32_t aDiv) const { return MyClass(mValue / aDiv); }
+};
+
+class RollingMeanSuite {
+ public:
+  RollingMeanSuite() = default;
+
+  void runTests() {
+    testZero();
+    testClear();
+    testRolling();
+    testClass();
+    testMove();
+  }
+
+ private:
+  void testZero() {
+    RollingMean<uint32_t, uint64_t> mean(3);
+    MOZ_RELEASE_ASSERT(mean.empty());
+  }
+
+  void testClear() {
+    RollingMean<uint32_t, uint64_t> mean(3);
+
+    mean.insert(4);
+    MOZ_RELEASE_ASSERT(mean.mean() == 4);
+
+    mean.clear();
+    MOZ_RELEASE_ASSERT(mean.empty());
+
+    mean.insert(3);
+    MOZ_RELEASE_ASSERT(mean.mean() == 3);
+  }
+
+  void testRolling() {
+    RollingMean<uint32_t, uint64_t> mean(3);
+
+    mean.insert(10);
+    MOZ_RELEASE_ASSERT(mean.mean() == 10);
+
+    mean.insert(20);
+    MOZ_RELEASE_ASSERT(mean.mean() == 15);
+
+    mean.insert(35);
+    MOZ_RELEASE_ASSERT(mean.mean() == 21);
+
+    mean.insert(5);
+    MOZ_RELEASE_ASSERT(mean.mean() == 20);
+
+    mean.insert(10);
+    MOZ_RELEASE_ASSERT(mean.mean() == 16);
+  }
+
+  void testClass() {
+    RollingMean<MyClass, MyClass> mean(3);
+
+    mean.insert(MyClass(4));
+    MOZ_RELEASE_ASSERT(mean.mean() == MyClass(4));
+
+    mean.clear();
+    MOZ_RELEASE_ASSERT(mean.empty());
+  }
+
+  void testMove() {
+    RollingMean<uint32_t, uint64_t> mean(3);
+    mean = RollingMean<uint32_t, uint64_t>(4);
+    MOZ_RELEASE_ASSERT(mean.maxValues() == 4);
+
+    mean.insert(10);
+    MOZ_RELEASE_ASSERT(mean.mean() == 10);
+
+    mean = RollingMean<uint32_t, uint64_t>(3);
+    mean.insert(30);
+    mean.insert(40);
+    mean.insert(50);
+    mean.insert(60);
+    MOZ_RELEASE_ASSERT(mean.mean() == 50);
+  }
+};
+
+int main() {
+  RollingMeanSuite suite;
+  suite.runTests();
+  return 0;
+}