Project: Add stopLoading() method

Author: adazem009

include/scratchcpp/project.h

@@ -29,6 +29,7 @@ class LIBSCRATCHCPP_EXPORT Project
         Project(const Project &) = delete;
 
         bool load();
+        void stopLoading();
 
         void start();
         void run();

src/project.cpp

@@ -1,8 +1,10 @@
 // SPDX-License-Identifier: Apache-2.0
 
 #include <scratchcpp/project.h>
+#include <iostream>
 
 #include "project_p.h"
+#include "internal/projectdownloader.h"
 
 using namespace libscratchcpp;
 
@@ -27,6 +29,14 @@ bool Project::load()
     return impl->load();
 }
 
+/*! Cancels project loading if loading in another thread. */
+void Project::stopLoading()
+{
+    std::cout << "Aborting project loading..." << std::endl;
+    impl->stopLoading = true;
+    impl->downloader->cancel();
+}
+
 /*!
  * Calls all "when green flag clicked" blocks.
  * \note Nothing will happen until run() or frame() is called.

src/project_p.cpp

@@ -47,6 +47,8 @@ bool ProjectPrivate::load()
 
 bool ProjectPrivate::tryLoad(IProjectReader *reader)
 {
+    stopLoading = false;
+
     // Load from URL
     ProjectUrl url(fileName);
 
@@ -57,8 +59,18 @@ bool ProjectPrivate::tryLoad(IProjectReader *reader)
             return false;
         }
 
+        if (stopLoading) {
+            loadingAborted();
+            return false;
+        }
+
         bool ret = reader->loadData(downloader->json());
 
+        if (stopLoading) {
+            loadingAborted();
+            return false;
+        }
+
         if (!ret)
             return false;
 
@@ -91,7 +103,14 @@ bool ProjectPrivate::tryLoad(IProjectReader *reader)
         }
 
         // Download assets
-        if (!downloader->downloadAssets(assetNames)) {
+        ret = downloader->downloadAssets(assetNames);
+
+        if (stopLoading) {
+            loadingAborted();
+            return false;
+        }
+
+        if (!ret) {
             std::cerr << "Failed to download the project assets." << std::endl;
             return false;
         }
@@ -113,7 +132,18 @@ bool ProjectPrivate::tryLoad(IProjectReader *reader)
             return false;
         }
 
+        if (stopLoading) {
+            loadingAborted();
+            return false;
+        }
+
         bool ret = reader->load();
+
+        if (stopLoading) {
+            loadingAborted();
+            return false;
+        }
+
         if (!ret)
             return false;
     }
@@ -125,9 +155,20 @@ bool ProjectPrivate::tryLoad(IProjectReader *reader)
     engine->setExtensions(reader->extensions());
     engine->setUserAgent(reader->userAgent());
     engine->compile();
+
+    if (stopLoading) {
+        loadingAborted();
+        return false;
+    }
+
     return true;
 }
 
+void ProjectPrivate::loadingAborted()
+{
+    std::cout << "Loading aborted." << std::endl;
+}
+
 void ProjectPrivate::start()
 {
     engine->start();

src/project_p.h

@@ -21,6 +21,7 @@ struct ProjectPrivate
 
         bool load();
         bool tryLoad(IProjectReader *reader);
+        void loadingAborted();
 
         void start();
         void run();
@@ -29,6 +30,7 @@ struct ProjectPrivate
         sigslot::signal<unsigned int, unsigned int> &downloadProgressChanged();
 
         std::string fileName;
+        std::atomic<bool> stopLoading = false;
         std::shared_ptr<IEngine> engine = nullptr;
 
         static IProjectDownloaderFactory *downloaderFactory;

test/project/project_test.cpp

@@ -115,3 +115,17 @@ TEST(LoadProjectTest, DownloadProgressChanged)
     EXPECT_CALL(*downloader, downloadProgressChanged).WillOnce(ReturnRef(signal));
     ASSERT_EQ(&p.downloadProgressChanged(), &signal);
 }
+
+TEST(LoadProjectTest, AbortDownload)
+{
+    ProjectDownloaderFactoryMock factory;
+    auto downloader = std::make_shared<ProjectDownloaderMock>();
+    ProjectPrivate::downloaderFactory = &factory;
+
+    EXPECT_CALL(factory, create()).WillOnce(Return(downloader));
+    Project p;
+    ProjectPrivate::downloaderFactory = nullptr;
+
+    EXPECT_CALL(*downloader, cancel());
+    p.stopLoading();
+}