Test string builder generation

2 files changed, 23 insertions, 20 deletions

diff --git a/src/gleam/json.gleam b/src/gleam/json.gleam
index 43c8dda..b509d7c 100644
--- a/src/gleam/json.gleam
+++ b/src/gleam/json.gleam
@@ -13,22 +13,18 @@ pub type DecodeError {
 }
 
 // TODO: document
-// TODO: test
 pub external fn decode(String) -> Result(Dynamic, DecodeError) =
   "thoas" "decode"
 
 // TODO: document
-// TODO: test
 pub external fn to_string(Json) -> String =
   "gleam_json_ffi" "json_to_string"
 
 // TODO: document
-// TODO: test
-external fn to_string_builder(Json) -> String =
-  "thoas_encode" "encode"
+pub external fn to_string_builder(Json) -> StringBuilder =
+  "gleam_json_ffi" "json_to_iodata"
 
 // TODO: document
-// TODO: test
 pub external fn string(input: String) -> Json =
   "thoas_encode" "string"
 
@@ -38,7 +34,6 @@ pub external fn bool(input: Bool) -> Json =
   "thoas_encode" "boolean"
 
 // TODO: document
-// TODO: test
 pub external fn int(input: Int) -> Json =
   "thoas_encode" "integer"
 
diff --git a/test/gleam_json_test.gleam b/test/gleam_json_test.gleam
index 80849e3..7617ebb 100644
--- a/test/gleam_json_test.gleam
+++ b/test/gleam_json_test.gleam
@@ -1,6 +1,7 @@
 import gleam/dynamic
-import gleam/json
+import gleam/json.{Json}
 import gleam/option.{None, Some}
+import gleam/string_builder
 import gleam/result
 import gleeunit
 import gleeunit/should
@@ -27,34 +28,41 @@ pub fn decode_unexpected_byte_test() {
 
 pub fn encode_string_test() {
   json.string("hello")
-  |> json.to_string()
-  |> should.equal("\"hello\"")
+  |> should_encode("\"hello\"")
 }
 
 pub fn encode_null_test() {
   json.null()
-  |> json.to_string()
-  |> should.equal("null")
+  |> should_encode("null")
 }
 
 pub fn encode_object_test() {
   json.object([#("foo", json.int(5))])
-  |> json.to_string()
-  |> should.equal("{\"foo\":5}")
+  |> should_encode("{\"foo\":5}")
 }
 
 pub fn encode_list_test() {
   json.list([json.int(5), json.int(6)])
-  |> json.to_string()
-  |> should.equal("[5,6]")
+  |> should_encode("[5,6]")
 }
 
-pub fn encode_nullable_test() {
+pub fn encode_nullable_some_test() {
   json.nullable(Some(5), json.int)
-  |> json.to_string()
-  |> should.equal("5")
+  |> should_encode("5")
+}
 
+pub fn encode_nullable_none_test() {
   json.nullable(None, json.int)
+  |> should_encode("null")
+}
+
+fn should_encode(data: Json, expected: String) {
+  data
   |> json.to_string()
-  |> should.equal("null")
+  |> should.equal(expected)
+
+  data
+  |> json.to_string_builder
+  |> string_builder.to_string
+  |> should.equal(json.to_string(data))
 }