diff --git a/tests/basics/string_fstring.py b/tests/basics/string_fstring.py
index d94cc0cd3e..200065e9d9 100644
--- a/tests/basics/string_fstring.py
+++ b/tests/basics/string_fstring.py
@@ -79,3 +79,14 @@ print(
 # Raw f-strings.
 print(rf"\r\a\w {'f'} \s\t\r\i\n\g")
 print(fr"\r{x}")
+
+# Format specifiers with nested replacement fields
+space = 5
+prec = 2
+print(f"{3.14:{space}.{prec}}")
+
+space_prec = "5.2"
+print(f"{3.14:{space_prec}}")
+
+radix = "x"
+print(f"{314:{radix}}")