[fix] Review + add more cases in unittest

diagrams/__init__.py

@@ -160,22 +160,13 @@ class Diagram:
         return self.dot.pipe(format="png")
 
     def _validate_direction(self, direction: str) -> bool:
-        direction = direction.upper()
-        if direction in self.__directions:
-            return True
-        return False
+        return direction.upper() in self.__directions
 
     def _validate_curvestyle(self, curvestyle: str) -> bool:
-        curvestyle = curvestyle.lower()
-        if curvestyle in self.__curvestyles:
-            return True
-        return False
+        return curvestyle.lower() in self.__curvestyles
 
     def _validate_outformat(self, outformat: str) -> bool:
-        outformat = outformat.lower()
-        if outformat in self.__outformats:
-            return True
-        return False
+        return outformat.lower() in self.__outformats
 
     def node(self, nodeid: str, label: str, **attrs) -> None:
         """Create a new node."""

tests/test_diagram.py

@@ -25,7 +25,7 @@ class DiagramTest(unittest.TestCase):
 
     def test_validate_direction(self):
         # Normal directions.
-        for dir in ("TB", "BT", "LR", "RL"):
+        for dir in ("TB", "BT", "LR", "RL", "tb"):
             Diagram(direction=dir)
 
         # Invalid directions.
@@ -35,7 +35,7 @@ class DiagramTest(unittest.TestCase):
 
     def test_validate_curvestyle(self):
         # Normal directions.
-        for cvs in ("ortho", "curved"):
+        for cvs in ("ortho", "curved", "CURVED"):
             Diagram(curvestyle=cvs)
 
         # Invalid directions.
@@ -45,7 +45,7 @@ class DiagramTest(unittest.TestCase):
 
     def test_validate_outformat(self):
         # Normal output formats.
-        for fmt in ("png", "jpg", "svg", "pdf"):
+        for fmt in ("png", "jpg", "svg", "pdf", "PNG"):
             Diagram(outformat=fmt)
 
         # Invalid output formats.