Issue 5183 - Provide async interface for FileSystem

test/BaseJsTest.h

Index: test/BaseJsTest.h
===================================================================
--- a/test/BaseJsTest.h
+++ b/test/BaseJsTest.h
@@ -13,19 +13,56 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #ifndef MOCKS_H
 #define MOCKS_H
 
+#include <thread>
+
 #include <AdblockPlus.h>
 #include <gtest/gtest.h>
 #include "../src/Thread.h"
+#include "../src/Utils.h"
+
+class Sync
+{
+public:
+  Sync()
+    : set(false)
+  {
+  }
+  void Wait(int sec = 20)
+  {
+    std::unique_lock<std::mutex> lock(mutex);
+    while (!set)
+      cv.wait_for(lock, std::chrono::seconds(sec));
+  }
+  void Set(const std::string& error_ = std::string())
+  {
+    {
+      std::unique_lock<std::mutex> lock(mutex);
+      set = true;
+      error = error_;
+    }
+    cv.notify_all();
+  }
+  std::string GetError()
+  {
+    std::unique_lock<std::mutex> lock(mutex);
+    return error;
+  }
+private:
+  std::mutex mutex;
+  std::condition_variable cv;
+  bool set;
+  std::string error;
+};
 
 // Strictly speaking in each test there should be a special implementation of
 // an interface, which is merely referenced by a wrapper and the latter should
 // be injected into JsEngine or what ever. However the everthing a test often
 // actually needs is the access to pending tasks. Therefore instantiation of
 // implemenation of an interface, creation of shared tasks and sharing them
 // with tasks in test is located in this class.
 //
@@ -97,96 +134,166 @@
 public:
   void operator()(LogLevel logLevel, const std::string& message,
         const std::string& source)
   {
     throw std::runtime_error("Unexpected error: " + message);
   }
 };
 
-class ThrowingFileSystem : public AdblockPlus::FileSystem
+class ThrowingFileSystem : public AdblockPlus::IFileSystem, public AdblockPlus::FileSystem
 {
 public:
   std::shared_ptr<std::istream> Read(const std::string& path) const
   {
     throw std::runtime_error("Not implemented");
   }
+  void Read(const std::string& path,
+            const ReadCallback& callback) const
+  {
+    throw std::runtime_error("Not implemented");
+  }
 
   void Write(const std::string& path, std::istream& content)
   {
     throw std::runtime_error("Not implemented");
   }
+  void Write(const std::string& path, std::shared_ptr<std::istream> data,
+             const Callback& callback)
+  {
+    throw std::runtime_error("Not implemented");
+  }
 
   void Move(const std::string& fromPath, const std::string& toPath)
   {
     throw std::runtime_error("Not implemented");
   }
+  void Move(const std::string& fromPath, const std::string& toPath,
+            const Callback& callback)
+  {
+    throw std::runtime_error("Not implemented");
+  }
 
   void Remove(const std::string& path)
   {
     throw std::runtime_error("Not implemented");
   }
+  void Remove(const std::string& path, const Callback& callback)
+  {
+    throw std::runtime_error("Not implemented");
+  }
 
   StatResult Stat(const std::string& path) const
   {
     throw std::runtime_error("Not implemented");
   }
+  void Stat(const std::string& path,
+            const StatCallback& callback) const
+  {
+    throw std::runtime_error("Not implemented");
+  }
 
   std::string Resolve(const std::string& path) const
   {
     throw std::runtime_error("Not implemented");
   }
-
 };
 
 class ThrowingWebRequest : public AdblockPlus::IWebRequest
 {
 public:
   void GET(const std::string& url, const AdblockPlus::HeaderList& requestHeaders, const GetCallback&) override
   {
     throw std::runtime_error("Unexpected GET: " + url);
   }
 };
 
-class LazyFileSystem : public AdblockPlus::FileSystem
+class LazyFileSystem : public AdblockPlus::IFileSystem, public AdblockPlus::FileSystem
 {
 public:
   std::shared_ptr<std::istream> Read(const std::string& path) const
   {
     std::string dummyData("");
     if (path == "patterns.ini")
       dummyData = "# Adblock Plus preferences\n[Subscription]\nurl=~fl~";
     else if (path == "prefs.json")
       dummyData = "{}";
     return std::shared_ptr<std::istream>(new std::istringstream(dummyData));
   }
 
+  void Read(const std::string& path, const ReadCallback& callback) const
+  {
+    std::thread([this, path, callback]
+    {
+      auto result = Read(path);
+      std::string content = AdblockPlus::Utils::Slurp(*result);
+      callback(std::move(content), "");
+    }).detach();
+  }
+
   void Write(const std::string& path, std::istream& content)
   {
   }
 
+  void Write(const std::string& path, std::shared_ptr<std::istream> data,
+             const Callback& callback)
+  {
+    std::thread([this, path, data, callback]
+    {
+      Write(path, *data);
+      callback("");
+    }).detach();
+  }
+
   void Move(const std::string& fromPath, const std::string& toPath)
   {
   }
 
+  void Move(const std::string& fromPath, const std::string& toPath,
+            const Callback& callback)
+  {
+    std::thread([this, fromPath, toPath, callback]
+    {
+      Move(fromPath, toPath);
+      callback("");
+    }).detach();
+  }
+
   void Remove(const std::string& path)
   {
   }
 
+  void Remove(const std::string& path, const Callback& callback)
+  {
+    std::thread([this, path, callback]
+    {
+      Remove(path);
+      callback("");
+    }).detach();
+  }
+
   StatResult Stat(const std::string& path) const
   {
     StatResult result;
     if (path == "patterns.ini")
     {
       result.exists = true;
       result.isFile = true;
     }
     return result;
   }
 
+  void Stat(const std::string& path, const StatCallback& callback) const
+  {
+    std::thread([this, path, callback]
+    {
+      callback(Stat(path), "");
+    }).detach();
+  }
+
   std::string Resolve(const std::string& path) const
   {
     return path;
   }
 };
 
 class NoopWebRequest : public AdblockPlus::IWebRequest
 {