add limitations of size

blink.py

@@ -6,7 +6,10 @@ BLUE = (0, 0, 255)
 
 
 class Thing:
-    def __init__(self, matrix=[], file=None, width=12, height=12):
+    def __init__(self, matrix=[], file=None, max_width=12, max_height=12):
+
+        self.max_width = max_width
+        self.max_height = max_height
 
         if file is None:
             self.matrix = matrix
@@ -21,7 +24,8 @@ class Thing:
         print(f'>> loading image from {file}')
 
         img = Image.open(file)
-        w, h = img.size
+
+        w, h = self._limit_dimensions(img.size)
 
         y = 0
         result = []
@@ -40,6 +44,22 @@ class Thing:
 
         self.matrix = result
 
+    def _limit_dimensions(self, dim):
+        """
+        Accepts a tuple(width, height) and returns a new tuple(width, height)
+        where both values don't exceed this objects maximum dimensions
+        """
+
+        w, h = dim
+
+        if w > self.max_width:
+            w = self.max_width
+
+        if h > self.max_height:
+            h = self.max_height
+
+        return (w, h)
+
     def console_print(self):
         """Prints the pixel matrix in this object to the console.
 

readme.md

+run tests:
+
+```
+python3 -m unittest -v test
+```
+

test.py

@@ -36,6 +36,13 @@ class TestBlink(unittest.TestCase):
 
         self.assertEqual(t.matrix, expected)
 
+    def test_limit_dimensions(self):
+
+        t = blink.Thing()
+        actual = t._limit_dimensions((20, 20))
+
+        self.assertEqual(actual, (12, 12))
+
 
 if __name__ == "__main__":
     unittest.main()