diff --git a/test/testAsync.cpp b/test/testAsync.cpp
index 4530f1d9..edc6dde7 100644
--- a/test/testAsync.cpp
+++ b/test/testAsync.cpp
@@ -10,6 +10,8 @@ static unsigned cnt = 0;
 
 bool tvgUpdateCmds(tvg::Canvas* canvas)
 {
+   if (!canvas) return false;
+
     auto t = ecore_time_get();
 
     //Explicitly clear all retained paint nodes.
diff --git a/test/testBlending.cpp b/test/testBlending.cpp
index 7db82019..5477b3b6 100644
--- a/test/testBlending.cpp
+++ b/test/testBlending.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     canvas->reserve(5);
 
     //Prepare Round Rectangle
diff --git a/test/testBoundary.cpp b/test/testBoundary.cpp
index a2bb1d8e..57a3d6c6 100644
--- a/test/testBoundary.cpp
+++ b/test/testBoundary.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     canvas->reserve(5);             //reserve 5 shape nodes (optional)
 
     //Prepare Shape1
diff --git a/test/testCommon.h b/test/testCommon.h
index f1769566..13ac86ab 100644
--- a/test/testCommon.h
+++ b/test/testCommon.h
@@ -12,14 +12,13 @@ using namespace std;
 /************************************************************************/
 
 void tvgSwTest(uint32_t* buffer);
+void drawSwView(void* data, Eo* obj);
 
 void win_del(void *data, Evas_Object *o, void *ev)
 {
    elm_exit();
 }
 
-void drawSwView(void* data, Eo* obj);
-
 static Eo* createSwView()
 {
     static uint32_t buffer[WIDTH * HEIGHT];
diff --git a/test/testCustomTransform.cpp b/test/testCustomTransform.cpp
index 00a3bc30..f95e41ef 100644
--- a/test/testCustomTransform.cpp
+++ b/test/testCustomTransform.cpp
@@ -7,6 +7,8 @@ tvg::Shape* pShape = nullptr;
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape1
     auto shape = tvg::Shape::gen();
 
@@ -33,6 +35,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     /* Update shape directly.
        You can update only necessary properties of this shape,
        while retaining other properties. */
@@ -202,4 +206,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testDirectUpdate.cpp b/test/testDirectUpdate.cpp
index 164ff612..3c275b62 100644
--- a/test/testDirectUpdate.cpp
+++ b/test/testDirectUpdate.cpp
@@ -7,6 +7,8 @@ tvg::Shape* pShape = nullptr;
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape
     auto shape = tvg::Shape::gen();
 
@@ -26,6 +28,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     /* Update shape directly.
        You can update only necessary properties of this shape,
        while retaining other properties. */
diff --git a/test/testGradientTransform.cpp b/test/testGradientTransform.cpp
index a97ec70d..4fa426be 100644
--- a/test/testGradientTransform.cpp
+++ b/test/testGradientTransform.cpp
@@ -9,6 +9,8 @@ tvg::Shape* pShape3 = nullptr;
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape1
     auto shape = tvg::Shape::gen();
 
@@ -83,6 +85,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     /* Update shape directly.
        You can update only necessary properties of this shape,
        while retaining other properties. */
@@ -230,4 +234,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testLinearGradient.cpp b/test/testLinearGradient.cpp
index 90656fce..f98fc970 100644
--- a/test/testLinearGradient.cpp
+++ b/test/testLinearGradient.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     canvas->reserve(3);                          //reserve 3 shape nodes (optional)
 
     //Prepare Round Rectangle
diff --git a/test/testMultiShapes.cpp b/test/testMultiShapes.cpp
index d81f7098..5a6d34f9 100644
--- a/test/testMultiShapes.cpp
+++ b/test/testMultiShapes.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     canvas->reserve(3);                          //reserve 3 shape nodes (optional)
 
     //Prepare Round Rectangle
diff --git a/test/testPath.cpp b/test/testPath.cpp
index b3a265ea..52c56efb 100644
--- a/test/testPath.cpp
+++ b/test/testPath.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Star
     auto shape1 = tvg::Shape::gen();
 
diff --git a/test/testPathCopy.cpp b/test/testPathCopy.cpp
index 724b8b4f..0ae364b7 100644
--- a/test/testPathCopy.cpp
+++ b/test/testPathCopy.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     /* Star */
 
     //Prepare Path Commands
@@ -182,4 +184,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testRadialGradient.cpp b/test/testRadialGradient.cpp
index c80cb03f..a6c10ba1 100644
--- a/test/testRadialGradient.cpp
+++ b/test/testRadialGradient.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     canvas->reserve(3);                          //reserve 3 shape nodes (optional)
 
     //Prepare Round Rectangle
@@ -168,4 +170,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testScene.cpp b/test/testScene.cpp
index c835a921..5b12020e 100644
--- a/test/testScene.cpp
+++ b/test/testScene.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Create a Scene
     auto scene = tvg::Scene::gen();
     scene->reserve(3);   //reserve 3 shape nodes (optional)
@@ -175,4 +177,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testSceneTransform.cpp b/test/testSceneTransform.cpp
index 9597101d..0d0be8e7 100644
--- a/test/testSceneTransform.cpp
+++ b/test/testSceneTransform.cpp
@@ -8,6 +8,8 @@ tvg::Scene* pScene2 = nullptr;
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Create a Scene1
     auto scene = tvg::Scene::gen();
     pScene1 = scene.get();
@@ -90,6 +92,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     /* Update scene directly.
        You can update only necessary properties of this scene,
        while retaining other properties. */
@@ -226,4 +230,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testShape.cpp b/test/testShape.cpp
index 7788817f..88519d05 100644
--- a/test/testShape.cpp
+++ b/test/testShape.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Prepare a Shape (Rectangle + Rectangle + Circle + Circle)
     auto shape1 = tvg::Shape::gen();
     shape1->appendRect(0, 0, 200, 200, 0, 0);          //x, y, w, h, rx, ry
@@ -118,4 +120,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testStroke.cpp b/test/testStroke.cpp
index 36f2a948..91748727 100644
--- a/test/testStroke.cpp
+++ b/test/testStroke.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape 1
     auto shape1 = tvg::Shape::gen();
     shape1->appendRect(50, 50, 200, 200, 0, 0);
@@ -165,4 +167,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testStrokeLine.cpp b/test/testStrokeLine.cpp
index 894c6950..445f8406 100644
--- a/test/testStrokeLine.cpp
+++ b/test/testStrokeLine.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Test for Stroke Width
     for (int i = 0; i < 10; ++i) {
         auto shape = tvg::Shape::gen();
@@ -202,4 +204,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testSvg.cpp b/test/testSvg.cpp
index 65fe9d7a..b8eb2ba2 100644
--- a/test/testSvg.cpp
+++ b/test/testSvg.cpp
@@ -31,6 +31,8 @@ void svgDirCallback(const char* name, const char* path, void* data)
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Background
     auto shape = tvg::Shape::gen();
     shape->appendRect(0, 0, WIDTH, HEIGHT, 0, 0);    //x, y, w, h, rx, ry
@@ -142,4 +144,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testTransform.cpp b/test/testTransform.cpp
index 6d0edbf1..7529d140 100644
--- a/test/testTransform.cpp
+++ b/test/testTransform.cpp
@@ -9,6 +9,8 @@ tvg::Shape* pShape3 = nullptr;
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape1
     auto shape = tvg::Shape::gen();
 
@@ -46,6 +48,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     /* Update shape directly.
        You can update only necessary properties of this shape,
        while retaining other properties. */
@@ -193,4 +197,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}
diff --git a/test/testUpdate.cpp b/test/testUpdate.cpp
index 0d007381..9c213436 100644
--- a/test/testUpdate.cpp
+++ b/test/testUpdate.cpp
@@ -6,6 +6,8 @@
 
 void tvgDrawCmds(tvg::Canvas* canvas)
 {
+    if (!canvas) return;
+
     //Shape
     auto shape = tvg::Shape::gen();
     shape->appendRect(-100, -100, 200, 200, 0, 0);
@@ -15,6 +17,8 @@ void tvgDrawCmds(tvg::Canvas* canvas)
 
 void tvgUpdateCmds(tvg::Canvas* canvas, float progress)
 {
+    if (!canvas) return;
+
     //Explicitly clear all retained paint nodes.
     if (canvas->clear() != tvg::Result::Success) return;
 
@@ -154,4 +158,4 @@ int main(int argc, char **argv)
         cout << "engine is not supported" << endl;
     }
     return 0;
-}
\ No newline at end of file
+}