1 files changed, 12 insertions, 3 deletions
diff --git a/src/iodata.gleam b/src/iodata.gleam
index 1b28577..4d81e38 100644
--- a/src/iodata.gleam
+++ b/src/iodata.gleam
@@ -1,11 +1,10 @@
 import any
-
-// TODO: Tests
+import expect
 
 pub external type Iodata;
 
 pub external fn prepend(Iodata, String) -> Iodata =
-  "gleam__stdlib" "iodata_concat";
+  "gleam__stdlib" "iodata_prepend";
 
 pub external fn append(Iodata, String) -> Iodata =
   "gleam__stdlib" "iodata_append";
@@ -18,3 +17,13 @@ pub external fn to_string(Iodata) -> String =
 
 pub external fn byte_size(Iodata) -> Int =
   "erlang" "iolist_size";
+
+test iodata {
+  let iodata = from(["ello"])
+    |> append(_, ",")
+    |> append(_, " world!")
+    |> prepend(_, "H")
+
+  expect:equal(to_string(iodata), "Hello, world!")
+  expect:equal(byte_size(iodata), 13)
+}