diff --git a/main.py b/main.py
index 2df8be1e..71e706d2 100644
--- a/main.py
+++ b/main.py
@@ -5,7 +5,7 @@
 import sys
 import asyncio
 
-if os.name == "nt": # If on windows
+if os.name == "nt":  # If on windows
     asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
 
 from qtpy.QtWidgets import QApplication
diff --git a/opencodeblocks/graphics/blocks/codeblock.py b/opencodeblocks/graphics/blocks/codeblock.py
index 782c8875..ea2271f1 100644
--- a/opencodeblocks/graphics/blocks/codeblock.py
+++ b/opencodeblocks/graphics/blocks/codeblock.py
@@ -141,8 +141,7 @@ def init_run_button(self):
 
     def run_code(self):
         """Run the code in the block"""
-        code = self.source_editor.text()
-        self.source = code
+        self.source = self.source_editor.text()
         # Create a worker to handle execution
         worker = Worker(self.source_editor.kernel, self.source)
         worker.signals.stdout.connect(self.handle_stdout)
diff --git a/tests/integration/blocks/__init__.py b/tests/integration/blocks/__init__.py
new file mode 100644
index 00000000..da40e082
--- /dev/null
+++ b/tests/integration/blocks/__init__.py
@@ -0,0 +1,6 @@
+# OpenCodeBlock an open-source tool for modular visual programing in python
+# Copyright (C) 2021 Mathïs FEDERICO <https://www.gnu.org/licenses/>
+
+"""
+Integration tests for blocks behavior.
+"""
diff --git a/tests/integration/blocks/test_block.py b/tests/integration/blocks/test_block.py
new file mode 100644
index 00000000..3c741b46
--- /dev/null
+++ b/tests/integration/blocks/test_block.py
@@ -0,0 +1,73 @@
+# OpenCodeBlock an open-source tool for modular visual programing in python
+# Copyright (C) 2021 Mathïs FEDERICO <https://www.gnu.org/licenses/>
+
+"""
+Integration tests for the OCBBlocks.
+"""
+
+import pytest
+import pyautogui
+from pytestqt.qtbot import QtBot
+
+from PyQt5.QtCore import QPointF
+
+from opencodeblocks.graphics.blocks.codeblock import OCBBlock
+from opencodeblocks.graphics.window import OCBWindow
+from opencodeblocks.graphics.widget import OCBWidget
+
+from tests.integration.utils import apply_function_inapp, CheckingQueue
+
+
+class TestBlocks:
+
+    @pytest.fixture(autouse=True)
+    def setup(self):
+        """ Setup reused variables. """
+        self.window = OCBWindow()
+        self.ocb_widget = OCBWidget()
+        self.subwindow = self.window.mdiArea.addSubWindow(self.ocb_widget)
+        self.subwindow.show()
+        self.block = OCBBlock(title="Testing block")
+
+    def test_create_blocks(self, qtbot: QtBot):
+        """ can be added to the scene. """
+        self.ocb_widget.scene.addItem(self.block)
+
+    def test_move_blocks(self, qtbot: QtBot):
+        """ can be dragged around with the mouse. """
+        self.ocb_widget.scene.addItem(self.block)
+
+        def testing_drag(msgQueue: CheckingQueue):
+            expected_move_amount = [70, -30]
+            pos_block = QPointF(self.block.pos().x(), self.block.pos().y())
+
+            pos_block.setX(
+                pos_block.x() + self.block.title_height + self.block.edge_size
+            )
+            pos_block.setY(pos_block.y() + self.block.title_height/2)
+
+            pos_block = self.ocb_widget.view.mapFromScene(pos_block)
+            pos_block = self.ocb_widget.view.mapToGlobal(pos_block)
+
+            pyautogui.moveTo(pos_block.x(), pos_block.y())
+            pyautogui.mouseDown(button="left")
+
+            iterations = 5
+            for i in range(iterations+1):
+                pyautogui.moveTo(
+                    pos_block.x() + expected_move_amount[0] * i / iterations,
+                    pos_block.y() + expected_move_amount[1] * i / iterations
+                )
+
+            pyautogui.mouseUp(button="left")
+
+            move_amount = [self.block.pos().x(), self.block.pos().y()]
+            # rectify because the scene can be zoomed :
+            move_amount[0] = move_amount[0] * self.ocb_widget.view.zoom
+            move_amount[1] = move_amount[1] * self.ocb_widget.view.zoom
+
+            msgQueue.check_equal(
+                move_amount, expected_move_amount, "Block moved by the correct amound")
+            msgQueue.stop()
+
+        apply_function_inapp(self.window, testing_drag)
diff --git a/tests/integration/blocks/test_codeblock.py b/tests/integration/blocks/test_codeblock.py
new file mode 100644
index 00000000..42f3cd2f
--- /dev/null
+++ b/tests/integration/blocks/test_codeblock.py
@@ -0,0 +1,68 @@
+# OpenCodeBlock an open-source tool for modular visual programing in python
+# Copyright (C) 2021 Mathïs FEDERICO <https://www.gnu.org/licenses/>
+
+"""
+Integration tests for the OCBCodeBlocks.
+"""
+
+import pyautogui
+import pytest
+from pytestqt.qtbot import QtBot
+
+from PyQt5.QtCore import QPointF
+
+from opencodeblocks.graphics.blocks.codeblock import OCBCodeBlock
+from opencodeblocks.graphics.window import OCBWindow
+from opencodeblocks.graphics.widget import OCBWidget
+
+from tests.integration.utils import apply_function_inapp, CheckingQueue
+
+
+class TestCodeBlocks:
+
+    @pytest.fixture(autouse=True)
+    def setup(self):
+        """ Setup reused variables. """
+        self.window = OCBWindow()
+        self.ocb_widget = OCBWidget()
+        self.subwindow = self.window.mdiArea.addSubWindow(self.ocb_widget)
+        self.subwindow.show()
+
+    def test_run_python(self, qtbot: QtBot):
+        """ run source code when run button is pressed. """
+
+        # Add a block with the source to the window
+        EXPRESSION = "3 + 5 * 2"
+        SOURCE_TEST = f'''print({EXPRESSION})'''
+        expected_result = str(3 + 5 * 2)
+
+        test_block = OCBCodeBlock(title="CodeBlock test", source=SOURCE_TEST)
+        self.ocb_widget.scene.addItem(test_block)
+
+        def testing_run(msgQueue: CheckingQueue):
+
+            msgQueue.check_equal(test_block.stdout.strip(), "")
+
+            pos_run_button = test_block.run_button.pos()
+            pos_run_button = QPointF(
+                pos_run_button.x() + test_block.run_button.width() / 2,
+                pos_run_button.y() + test_block.run_button.height() / 2,
+            )
+            pos_run_button = self.ocb_widget.view.mapFromScene(pos_run_button)
+            pos_run_button = self.ocb_widget.view.mapToGlobal(pos_run_button)
+
+            # Run the block by pressung the run button
+            pyautogui.moveTo(pos_run_button.x(), pos_run_button.y())
+            pyautogui.mouseDown(button="left")
+            pyautogui.mouseUp(button="left")
+
+            # qtbot.mouseMove(test_block.run_button)
+            # qtbot.mousePress(test_block.run_button,
+            #                  Qt.MouseButton.LeftButton, delay=1)
+            # qtbot.mouseRelease(test_block.run_button, Qt.MouseButton.LeftButton)
+
+            # When the execution becomes non-blocking for the UI, a refactor will be needed here.
+            msgQueue.check_equal(test_block.stdout.strip(), expected_result)
+            msgQueue.stop()
+
+        apply_function_inapp(self.window, testing_run)
diff --git a/tests/integration/test_blocks.py b/tests/integration/test_blocks.py
deleted file mode 100644
index 449f7763..00000000
--- a/tests/integration/test_blocks.py
+++ /dev/null
@@ -1,144 +0,0 @@
-# OpenCodeBlock an open-source tool for modular visual programing in python
-# Copyright (C) 2021 Mathïs FEDERICO <https://www.gnu.org/licenses/>
-
-"""
-Integration tests for the OCBBlocks.
-"""
-
-# Imports needed for testing
-import threading
-import queue
-import pytest
-from pytest_mock import MockerFixture
-import pytest_check as check
-import pyautogui
-
-# Packages tested
-from opencodeblocks.graphics.blocks.codeblock import OCBCodeBlock
-from opencodeblocks.graphics.window import OCBWindow
-from opencodeblocks.graphics.widget import OCBWidget
-
-from qtpy.QtWidgets import QApplication
-from PyQt5.QtCore import QPointF
-
-
-class TestBlocks:
-
-    @pytest.fixture(autouse=True)
-    def setup(self, mocker: MockerFixture):
-        """ Setup reused variables. """
-        self.window = OCBWindow()
-        self.ocb_widget = OCBWidget()
-        self.subwindow = self.window.mdiArea.addSubWindow(self.ocb_widget)
-
-        self.block1 = OCBCodeBlock(title="Testing block 1", source="print(1)")
-        self.block2 = OCBCodeBlock(title="Testing block 2", source="print(2)")
-
-    def test_create_blocks(self, qtbot):
-        """ can be added to the scene. """
-        self.ocb_widget.scene.addItem(self.block1)
-
-    def test_move_blocks(self, qtbot):
-        """ can be dragged around with the mouse. """
-        self.ocb_widget.scene.addItem(self.block1)
-        self.subwindow.show()
-
-        QApplication.processEvents()
-
-        expected_move_amount = [70, -30]
-        STOP_MSG = "stop"
-        CHECK_MSG = "check"
-
-        msgQueue = queue.Queue()
-
-        def testing_drag(msgQueue):
-            pos_block = QPointF(self.block1.pos().x(), self.block1.pos().y())
-
-            pos_block.setX(
-                pos_block.x() + self.block1.title_height + self.block1.edge_size
-            )
-            pos_block.setY(pos_block.y() + self.block1.title_height/2)
-
-            pos_block = self.ocb_widget.view.mapFromScene(pos_block)
-            pos_block = self.ocb_widget.view.mapToGlobal(pos_block)
-
-            pyautogui.moveTo(pos_block.x(), pos_block.y())
-            pyautogui.mouseDown(button="left")
-
-            iterations = 5
-            for i in range(iterations+1):
-                pyautogui.moveTo(
-                    pos_block.x() + expected_move_amount[0] * i / iterations,
-                    pos_block.y() + expected_move_amount[1] * i / iterations
-                )
-
-            pyautogui.mouseUp(button="left")
-
-            move_amount = [self.block1.pos().x(), self.block1.pos().y()]
-            # rectify because the scene can be zoomed :
-            move_amount[0] = move_amount[0] * self.ocb_widget.view.zoom
-            move_amount[1] = move_amount[1] * self.ocb_widget.view.zoom
-
-            msgQueue.put([
-                CHECK_MSG,
-                move_amount,
-                expected_move_amount,
-                "Block moved by the correct amound"
-            ])
-
-            msgQueue.put([STOP_MSG])
-
-        t = threading.Thread(target=testing_drag, args=(msgQueue,))
-        t.start()
-
-        while True:
-            QApplication.processEvents()
-            if not msgQueue.empty():
-                msg = msgQueue.get()
-                if msg[0] == STOP_MSG:
-                    break
-                elif msg[0] == CHECK_MSG:
-                    check.equal(msg[1], msg[2], msg[3])
-        t.join()
-        self.window.close()
-
-
-"""
-def test_running_python(qtbot):
-    # The blocks should run arbitrary python when unfocused
-    wnd = OCBWindow()
-    
-    EXPRESSION = "3 + 5 * 2"
-    SOURCE_TEST = \
-        '''
-            print(%s)
-        ''' % EXPRESSION
-    expected_result = str(eval(EXPRESSION))
-
-    # Let's add a block with the source to the window !
-    ocb_widget = OCBWidget()
-    test_block = OCBCodeBlock(title="Testing block", source=SOURCE_TEST)
-    ocb_widget.scene.addItem(test_block)
-    wnd.mdiArea.addSubWindow(ocb_widget)
-
-    # Let's run the block !
-    pyeditor = test_block.source_editor.widget()
-    # pyeditor.setModified(True)
-    # test_block._source = ""
-    QApplication.processEvents()
-    QtTest.QTest.mouseClick(pyeditor,Qt.MouseButton.LeftButton)
-    QApplication.processEvents()
-    QtTest.QTest.keyPress(pyeditor," ")
-    QApplication.processEvents()
-    
-    # Click outside the block to lose focus of the previous block.
-    # This will need to be changed by the click to the run button.
-    QtTest.QTest.mouseClick(ocb_widget,Qt.MouseButton.LeftButton)
-    QApplication.processEvents()
-
-    # When the execution becomes non-blocking for the UI, a refactor will be needed here.
-    result = test_block.stdout.strip()
-    
-    check.equal(expected_result,result)
-    wnd.close()
-"""
diff --git a/tests/integration/utils.py b/tests/integration/utils.py
new file mode 100644
index 00000000..956a7f7f
--- /dev/null
+++ b/tests/integration/utils.py
@@ -0,0 +1,52 @@
+# OpenCodeBlock an open-source tool for modular visual programing in python
+# Copyright (C) 2021 Mathïs FEDERICO <https://www.gnu.org/licenses/>
+
+"""
+Utilities functions for integration testing.
+"""
+
+import os
+import asyncio
+from typing import Callable
+
+import threading
+from queue import Queue
+from qtpy.QtWidgets import QApplication
+import pytest_check as check
+
+from opencodeblocks.graphics.window import OCBWindow
+
+STOP_MSG = "stop"
+CHECK_MSG = "check"
+
+
+class CheckingQueue(Queue):
+
+    def check_equal(self, a, b, msg=""):
+        self.put([CHECK_MSG, a, b, msg])
+
+    def stop(self):
+        self.put([STOP_MSG])
+
+
+def apply_function_inapp(window: OCBWindow, run_func: Callable):
+
+    if os.name == "nt":  # If on windows
+        asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
+
+    QApplication.processEvents()
+    msgQueue = CheckingQueue()
+    t = threading.Thread(target=run_func, args=(msgQueue,))
+    t.start()
+
+    stop = False
+    while not stop:
+        QApplication.processEvents()
+        if not msgQueue.empty():
+            msg = msgQueue.get()
+            if msg[0] == CHECK_MSG:
+                check.equal(msg[1], msg[2], msg[3])
+            elif msg[0] == STOP_MSG:
+                stop = True
+    t.join()
+    window.close()