Issue 5183 - Provide async interface for FileSystem

test/FileSystemJsObject.cpp

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <sstream>
 #include "BaseJsTest.h"
 #include "../src/Thread.h"
 
 namespace
 {
-  class MockFileSystem : public AdblockPlus::FileSystem
+  class MockFileSystem : public AdblockPlus::IFileSystem
   {
   public:
     bool success;
     std::string contentToRead;
     std::string lastWrittenPath;
     std::string lastWrittenContent;
     std::string movedFrom;
     std::string movedTo;
     std::string removedPath;
     mutable std::string statPath;
     bool statExists;
     bool statIsDirectory;
     bool statIsFile;
     int statLastModified;
 
     MockFileSystem() : success(true)
     {
     }
 
-    std::shared_ptr<std::istream> Read(const std::string& path) const
+    void Read(const std::string& path, const ReadCallback& callback) const
     {
       if (!success)
-        throw std::runtime_error("Unable to read " + path);
-      std::stringstream* const stream = new std::stringstream;
-      *stream << contentToRead;
-      return std::shared_ptr<std::istream>(stream);
+      {
+        callback(std::move(std::string()),

[sergei, 2017/06/16 15:05:56]

std::move is not necessary here

[hub, 2017/06/16 21:52:55]

Done.

+                 std::string("Unable to read " + path));

[sergei, 2017/06/16 15:05:56]

Actually, here and below one can simply pass "some string" without explicit
construction of std::string.

[hub, 2017/06/16 21:52:56]

Done.

+        return;
+      }
+      callback(std::move(std::string(contentToRead)), "");

[sergei, 2017/06/16 15:05:56]

std::move is not necessary here

[hub, 2017/06/16 21:52:55]

Done.

     }
 
-    void Write(const std::string& path, std::istream& data)
+    void Write(const std::string& path, std::shared_ptr<std::istream> data,
+               const Callback& callback)
     {
       if (!success)
-        throw std::runtime_error("Unable to write to " + path);
+      {
+        callback(std::string("Unable to write to " + path));
+        return;
+      }
       lastWrittenPath = path;
 
       std::stringstream content;
-      content << data.rdbuf();
+      content << data->rdbuf();
       lastWrittenContent = content.str();
+      callback("");
     }
 
-    void Move(const std::string& fromPath, const std::string& toPath)
+    void Move(const std::string& fromPath, const std::string& toPath,
+              const Callback& callback)
     {
       if (!success)
-        throw std::runtime_error("Unable to move " + fromPath + " to "
-                                 + toPath);
+      {
+        callback(std::string("Unable to move " + fromPath + " to "
+                             + toPath));
+        return;
+      }
       movedFrom = fromPath;
       movedTo = toPath;
+      callback("");
     }
 
-    void Remove(const std::string& path)
+    void Remove(const std::string& path, const Callback& callback)
     {
       if (!success)
-        throw std::runtime_error("Unable to remove " + path);
+      {
+        callback(std::string("Unable to remove " + path));
+        return;
+      }
       removedPath = path;
+      callback("");
     }
 
-    StatResult Stat(const std::string& path) const
+    void Stat(const std::string& path,
+              const StatCallback& callback) const
     {
+      StatResult result;
+      std::string error;
       if (!success)
-        throw std::runtime_error("Unable to stat " + path);
-      statPath = path;
-      StatResult result;
-      result.exists = statExists;
-      result.isDirectory = statIsDirectory;
-      result.isFile = statIsFile;
-      result.lastModified = statLastModified;
-      return result;
+        error = std::string("Unable to stat " + path);
+      else
+      {
+        statPath = path;
+        result.exists = statExists;
+        result.isDirectory = statIsDirectory;
+        result.isFile = statIsFile;
+        result.lastModified = statLastModified;
+      }
+      callback(result, error);
     }
 
     std::string Resolve(const std::string& path) const
     {
       if (!success)
         throw std::runtime_error("Unable to stat " + path);
       return path;
     }
   };
 
   void ReadFile(AdblockPlus::JsEnginePtr jsEngine, std::string& content,
                 std::string& error)
   {
     jsEngine->Evaluate("_fileSystem.read('', function(r) {result = r})");
     AdblockPlus::Sleep(50);
     content = jsEngine->Evaluate("result.content").AsString();
     error = jsEngine->Evaluate("result.error").AsString();
   }
 
   typedef std::shared_ptr<MockFileSystem> MockFileSystemPtr;
 
   class FileSystemJsObjectTest : public BaseJsTest
   {
   protected:
     MockFileSystemPtr mockFileSystem;
 
     void SetUp()
     {
-      BaseJsTest::SetUp();
       mockFileSystem = MockFileSystemPtr(new MockFileSystem);
-      jsEngine->SetFileSystem(mockFileSystem);
+      JsEngineCreationParameters params;
+      params.fileSystem = mockFileSystem;
+      jsEngine = CreateJsEngine(std::move(params));
     }
   };
 }
 
 TEST_F(FileSystemJsObjectTest, Read)
 {
   mockFileSystem->contentToRead = "foo";
   std::string content;
   std::string error;
   ReadFile(jsEngine, content, error);
@@ skipping 107 matching lines @@
   ASSERT_ANY_THROW(jsEngine->Evaluate("_fileSystem.stat('', '')"));
 }
 
 TEST_F(FileSystemJsObjectTest, StatError)
 {
   mockFileSystem->success = false;
   jsEngine->Evaluate("_fileSystem.stat('foo', function(r) {result = r})");
   AdblockPlus::Sleep(50);
   ASSERT_NE("", jsEngine->Evaluate("result.error").AsString());
 }