Merge pull request #17 from portfoliome/camel-case

Camel case

foil/_version.py

@@ -1,3 +1,3 @@
-version_info = (0, 1, 2)
+version_info = (0, 1, 3)
 
 __version__ = '.'.join(map(str, version_info))

foil/strings.py

@@ -0,0 +1,18 @@
+import re
+
+
+CAMEL_CASE_RE = re.compile(r'(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))')
+
+
+def camel_to_snake(s: str) -> str:
+    """Convert string from camel case to snake case."""
+
+    return CAMEL_CASE_RE.sub(r'_\1', s).strip().lower()
+
+
+def snake_to_camel(s: str) -> str:
+    """Convert string from snake case to camel case."""
+
+    fragments = s.split('_')
+
+    return fragments[0] + ''.join(x.title() for x in fragments[1:])

tests/test_strings.py

@@ -0,0 +1,18 @@
+import unittest
+
+from foil.strings import camel_to_snake, snake_to_camel
+
+
+class TestSnakeCamel(unittest.TestCase):
+
+    def test_camel_to_snake_case(self):
+        expected = 'hello_world'
+        result = camel_to_snake('helloWorld')
+
+        self.assertEqual(expected, result)
+
+    def test_snake_to_camel_case(self):
+        expected = '123HelloWorld'
+        result = snake_to_camel('123_hello_world')
+
+        self.assertEqual(expected, result)