File handling

src/files/test_file_methods.py

@@ -29,10 +29,10 @@ def test_file_methods():
     # argument. A from_what value of 0 measures from the beginning of the file, 1 uses the current
     # file position, and 2 uses the end of the file as the reference point. from_what can be omitted
     # and defaults to 0, using the beginning of the file as the reference point.
-    assert binary_file.seek(0) == 0  # Go to the 0th byte in the file
+    assert binary_file.seek(5) == 5  # Go to the 0th byte in the file
     assert binary_file.seek(6) == 6  # Go to the 6th byte in the file
 
-    assert binary_file.read(1) == '6'
+    assert binary_file.read(4) == '6789'
 
     # f.readline() reads a single line from the file; a newline character (\n) is left at the end
     # of the string, and is only omitted on the last line of the file if the file doesn’t end in a

src/files/test_file_reading.py

@@ -70,6 +70,23 @@ def test_files_open():
 
     assert file.closed
 
+    with open('src/files/write_file.txt', 'w') as file:
+        file.write('apple\n')
+        file.write('banana\n')
+
+    with open('src/files/write_file.txt', 'a') as file:
+        file.write('pineapple\n')
+
+
+    with open('src/files/write_file.txt', 'r') as file:
+        read_data = file.read()
+
+        assert read_data == (
+            'apple\n'
+            'banana\n'
+            'pineapple\n'
+        )
+
     # If you’re not using the with keyword, then you should call f.close() to close the file and
     # immediately free up any system resources used by it. If you don’t explicitly close a file,
     # Python’s garbage collector will eventually destroy the object and close the open file for you,

src/files/write_file.txt

@@ -0,0 +1,3 @@
+apple
+banana
+pineapple