From 78de722aa0c7ae80c743e38a5bfaab36dd41c21e Mon Sep 17 00:00:00 2001
From: Dave Borowitz <dborowitz@google.com>
Date: Fri, 22 Mar 2019 08:02:18 -0700
Subject: [PATCH] Add CacheStatsSubject

Change-Id: I07efea268113b73357b3f761ad47d7effe990fd9
---
 java/com/google/gerrit/truth/BUILD            |  1 +
 .../gerrit/truth/CacheStatsSubject.java       | 62 +++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 java/com/google/gerrit/truth/CacheStatsSubject.java

diff --git a/java/com/google/gerrit/truth/BUILD b/java/com/google/gerrit/truth/BUILD
index 786ae0d86a..6f958b12ca 100644
--- a/java/com/google/gerrit/truth/BUILD
+++ b/java/com/google/gerrit/truth/BUILD
@@ -4,6 +4,7 @@ java_library(
     srcs = glob(["**/*.java"]),
     visibility = ["//visibility:public"],
     deps = [
+        "//java/com/google/gerrit/common:annotations",
         "//lib:guava",
         "//lib/truth",
     ],
diff --git a/java/com/google/gerrit/truth/CacheStatsSubject.java b/java/com/google/gerrit/truth/CacheStatsSubject.java
new file mode 100644
index 0000000000..f1a9393a50
--- /dev/null
+++ b/java/com/google/gerrit/truth/CacheStatsSubject.java
@@ -0,0 +1,62 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.truth;
+
+import static com.google.common.truth.Truth.assertAbout;
+import static java.util.Objects.requireNonNull;
+
+import com.google.common.cache.CacheStats;
+import com.google.common.truth.FailureMetadata;
+import com.google.common.truth.Subject;
+import com.google.gerrit.common.UsedAt;
+import com.google.gerrit.common.UsedAt.Project;
+
+@UsedAt(Project.PLUGINS_ALL)
+public class CacheStatsSubject extends Subject<CacheStatsSubject, CacheStats> {
+  public static CacheStatsSubject assertThat(CacheStats stats) {
+    return assertAbout(CacheStatsSubject::new).that(stats);
+  }
+
+  public static CacheStats cloneStats(CacheStats other) {
+    return new CacheStats(
+        other.hitCount(),
+        other.missCount(),
+        other.loadSuccessCount(),
+        other.loadExceptionCount(),
+        other.totalLoadTime(),
+        other.evictionCount());
+  }
+
+  private CacheStats start = new CacheStats(0, 0, 0, 0, 0, 0);
+
+  private CacheStatsSubject(FailureMetadata failureMetadata, CacheStats stats) {
+    super(failureMetadata, stats);
+  }
+
+  public CacheStatsSubject since(CacheStats start) {
+    this.start = requireNonNull(start);
+    return this;
+  }
+
+  public void hasHitCount(int expectedHitCount) {
+    isNotNull();
+    check("hitCount()").that(actual().minus(start).hitCount()).isEqualTo(expectedHitCount);
+  }
+
+  public void hasMissCount(int expectedMissCount) {
+    isNotNull();
+    check("missCount()").that(actual().minus(start).missCount()).isEqualTo(expectedMissCount);
+  }
+}