fix(std/io): BufWriter/StringWriter bug (#6247)

1 files changed, 9 insertions, 0 deletions

diff --git a/std/io/writers_test.ts b/std/io/writers_test.ts
index a50f8b3d1..f27885f81 100644
--- a/std/io/writers_test.ts
+++ b/std/io/writers_test.ts
@@ -12,3 +12,12 @@ test("ioStringWriter", async function (): Promise<void> {
   await copy(r, w);
   assertEquals(w.toString(), "base0123456789");
 });
+
+test("ioStringWriterSync", function (): void {
+  const encoder = new TextEncoder();
+  const w = new StringWriter("");
+  w.writeSync(encoder.encode("deno"));
+  assertEquals(w.toString(), "deno");
+  w.writeSync(encoder.encode("\nland"));
+  assertEquals(w.toString(), "deno\nland");
+});