[CrOS Tether] Create HostScanCache, which caches scan results and inserts them into the network sta…

chromeos/components/tether/fake_host_scan_cache.h

Index: chromeos/components/tether/fake_host_scan_cache.h
diff --git a/chromeos/components/tether/fake_host_scan_cache.h b/chromeos/components/tether/fake_host_scan_cache.h
new file mode 100644
index 0000000000000000000000000000000000000000..1b390187e164cc9b89aad7522fc95de53d80506f
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+++ b/chromeos/components/tether/fake_host_scan_cache.h
@@ -0,0 +1,71 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROMEOS_COMPONENTS_TETHER_FAKE_HOST_SCAN_CACHE_H_
+#define CHROMEOS_COMPONENTS_TETHER_FAKE_HOST_SCAN_CACHE_H_
+
+#include <string>
+#include <unordered_map>
+
+#include "base/macros.h"
+#include "chromeos/components/tether/host_scan_cache.h"
+
+namespace chromeos {
+
+namespace tether {
+
+// Test double for HostScanCache which stores cache results in memory.
+class FakeHostScanCache : public HostScanCache {
+ public:
+  struct CacheEntry {
+    std::string device_name;
+    std::string carrier;
+    int battery_percentage;
+    int signal_strength;
+  };
+
+  FakeHostScanCache();
+  ~FakeHostScanCache() override;
+
+  // Getter and setter for the active host Tether network GUID. This value is
+  // used to implement the ClearCacheExceptForActiveHost() function.
+  std::string& active_host_tether_network_guid() {
+    return active_host_tether_network_guid_;
+  }
+  void set_active_host_tether_network_guid(
+      const std::string& active_host_tether_network_guid) {
+    active_host_tether_network_guid_ = active_host_tether_network_guid;
+  }
+
+  // Getters for contents of the cache.
+  const FakeHostScanCache::CacheEntry* GetCacheEntry(
+      const std::string& tether_network_guid);
+  size_t size() { return cache_.size(); }
+  bool empty() { return cache_.empty(); }
+  const std::unordered_map<std::string, FakeHostScanCache::CacheEntry> cache() {
+    return cache_;
+  }
+
+  // HostScanCache:
+  void SetHostScanResult(const std::string& tether_network_guid,
+                         const std::string& device_name,
+                         const std::string& carrier,
+                         int battery_percentage,
+                         int signal_strength) override;
+  bool RemoveHostScanResult(const std::string& tether_network_guid) override;
+  void ClearCacheExceptForActiveHost() override;
+  void OnPreviouslyConnectedHostIdsChanged() override;
+
+ private:
+  std::string active_host_tether_network_guid_;
+  std::unordered_map<std::string, CacheEntry> cache_;
+
+  DISALLOW_COPY_AND_ASSIGN(FakeHostScanCache);
+};
+
+}  // namespace tether
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_COMPONENTS_TETHER_FAKE_HOST_SCAN_CACHE_H_