Test string_utils module (#362)

src/whitenoise/string_utils.py

@@ -3,7 +3,7 @@
 
 def decode_if_byte_string(s, force_text=False):
     if isinstance(s, bytes):
-        s = s.decode("utf-8")
+        s = s.decode()
     if force_text and not isinstance(s, str):
         s = str(s)
     return s

tests/test_string_utils.py

@@ -0,0 +1,38 @@
+from __future__ import annotations
+
+from whitenoise.string_utils import decode_if_byte_string, ensure_leading_trailing_slash
+
+
+class DecodeIfByteStringTests:
+    def test_bytes(self):
+        assert decode_if_byte_string(b"abc") == "abc"
+
+    def test_unforced(self):
+        x = object()
+        assert decode_if_byte_string(x) is x
+
+    def test_forced(self):
+        x = object()
+        result = decode_if_byte_string(x, force_text=True)
+        assert isinstance(result, str)
+        assert result.startswith("<object object at ")
+
+
+class EnsureLeadingTrailingSlashTests:
+    def test_none(self):
+        assert ensure_leading_trailing_slash(None) == "/"
+
+    def test_empty(self):
+        assert ensure_leading_trailing_slash("") == "/"
+
+    def test_slash(self):
+        assert ensure_leading_trailing_slash("/") == "/"
+
+    def test_contents(self):
+        assert ensure_leading_trailing_slash("/foo/") == "/foo/"
+
+    def test_leading(self):
+        assert ensure_leading_trailing_slash("/foo") == "/foo"
+
+    def test_trailing(self):
+        assert ensure_leading_trailing_slash("foo/") == "/foo"