diff --git a/tests/util.py b/tests/util.py
index 0c792054..6f37548b 100644
--- a/tests/util.py
+++ b/tests/util.py
@@ -5,11 +5,11 @@ def get_capture_text(*paths: str) -> str:
     with open(
         pathlib.Path(__file__).parent.joinpath("captures", *paths), mode="rb"
     ) as file:
-        return file.read().decode()
+        return file.read().decode("utf-8")
 
 
 def set_capture_text(*paths: str, output: str) -> None:
     with open(
         pathlib.Path(__file__).parent.joinpath("captures", *paths), mode="wb"
     ) as file:
-        file.write(output.encode())
+        file.write(output.encode("utf-8"))