Implement looks_nextbackdrop block

Author: adazem009

src/blocks/looksblocks.cpp

@@ -61,6 +61,7 @@ void LooksBlocks::registerBlocks(IEngine *engine)
     engine->addCompileFunction(this, "looks_backdropnumbername", &compileBackdropNumberName);
     engine->addCompileFunction(this, "looks_costumenumbername", &compileCostumeNumberName);
     engine->addCompileFunction(this, "looks_switchbackdroptoandwait", &compileSwitchBackdropToAndWait);
+    engine->addCompileFunction(this, "looks_nextbackdrop", &compileNextBackdrop);
 }
 
 void LooksBlocks::onInit(IEngine *engine)
@@ -331,6 +332,12 @@ CompilerValue *LooksBlocks::compileSwitchBackdropToAndWait(Compiler *compiler)
     return nullptr;
 }
 
+CompilerValue *LooksBlocks::compileNextBackdrop(Compiler *compiler)
+{
+    compiler->addFunctionCallWithCtx("looks_nextbackdrop");
+    return nullptr;
+}
+
 extern "C" void looks_start_stack_timer(ExecutionContext *ctx, double duration)
 {
     ctx->stackTimer()->start(duration);
@@ -584,3 +591,8 @@ extern "C" bool looks_backdrop_promise(ExecutionContext *ctx)
 
     return false;
 }
+
+extern "C" void looks_nextbackdrop(ExecutionContext *ctx)
+{
+    looks_nextcostume(ctx->engine()->stage());
+}

src/blocks/looksblocks.h

@@ -47,6 +47,7 @@ class LooksBlocks : public IExtension
         static CompilerValue *compileBackdropNumberName(Compiler *compiler);
         static CompilerValue *compileCostumeNumberName(Compiler *compiler);
         static CompilerValue *compileSwitchBackdropToAndWait(Compiler *compiler);
+        static CompilerValue *compileNextBackdrop(Compiler *compiler);
 };
 
 } // namespace libscratchcpp

test/blocks/looks_blocks_test.cpp

@@ -2812,3 +2812,67 @@ TEST_F(LooksBlocksTest, SwitchBackdropToAndWait_Stage)
     thread.run();
     ASSERT_TRUE(thread.isFinished());
 }
+
+TEST_F(LooksBlocksTest, NextBackdrop_Sprite)
+{
+    auto sprite = std::make_shared<Sprite>();
+    auto costume1 = std::make_shared<Costume>("costume1", "a", "png");
+    auto testCostume = std::make_shared<Costume>("test", "c", "svg");
+    sprite->addCostume(costume1);
+    sprite->addCostume(testCostume);
+
+    auto stage = std::make_shared<Stage>();
+    auto backdrop1 = std::make_shared<Costume>("backdrop1", "a", "png");
+    auto backdrop2 = std::make_shared<Costume>("backdrop2", "b", "png");
+    auto testBackdrop = std::make_shared<Costume>("test", "c", "svg");
+    stage->addCostume(backdrop1);
+    stage->addCostume(backdrop2);
+    stage->addCostume(testBackdrop);
+
+    m_engine->setTargets({ stage, sprite });
+
+    ScriptBuilder builder(m_extension.get(), m_engine, sprite);
+
+    builder.addBlock("looks_nextbackdrop");
+    builder.build();
+
+    sprite->setCostumeIndex(0);
+    stage->setCostumeIndex(0);
+    builder.run();
+    ASSERT_EQ(sprite->costumeIndex(), 0);
+    ASSERT_EQ(stage->costumeIndex(), 1);
+
+    builder.run();
+    ASSERT_EQ(sprite->costumeIndex(), 0);
+    ASSERT_EQ(stage->costumeIndex(), 2);
+
+    builder.run();
+    ASSERT_EQ(sprite->costumeIndex(), 0);
+    ASSERT_EQ(stage->costumeIndex(), 0);
+}
+
+TEST_F(LooksBlocksTest, NextBackdrop_Stage)
+{
+    auto stage = std::make_shared<Stage>();
+    auto backdrop1 = std::make_shared<Costume>("backdrop1", "a", "png");
+    auto backdrop2 = std::make_shared<Costume>("backdrop2", "b", "png");
+    auto testBackdrop = std::make_shared<Costume>("test", "c", "svg");
+    stage->addCostume(backdrop1);
+    stage->addCostume(backdrop2);
+    stage->addCostume(testBackdrop);
+
+    ScriptBuilder builder(m_extension.get(), m_engine, stage);
+
+    builder.addBlock("looks_nextbackdrop");
+    builder.build();
+
+    stage->setCostumeIndex(0);
+    builder.run();
+    ASSERT_EQ(stage->costumeIndex(), 1);
+
+    builder.run();
+    ASSERT_EQ(stage->costumeIndex(), 2);
+
+    builder.run();
+    ASSERT_EQ(stage->costumeIndex(), 0);
+}