1 files changed, 66 insertions, 0 deletions
diff --git a/v_windows/v/vlib/io/multi_writer_test.v b/v_windows/v/vlib/io/multi_writer_test.v
new file mode 100644
index 0000000..2e317e8
--- /dev/null
+++ b/v_windows/v/vlib/io/multi_writer_test.v
@@ -0,0 +1,66 @@
+module io
+
+fn test_multi_writer_write_successful() {
+	w0 := TestWriter{}
+	w1 := TestWriter{}
+	mut mw := new_multi_writer(w0, w1)
+	n := mw.write('0123456789'.bytes()) or {
+		assert false
+		return
+	}
+	assert n == 10
+	assert w0.bytes == '0123456789'.bytes()
+	assert w1.bytes == '0123456789'.bytes()
+}
+
+fn test_multi_writer_write_incomplete() {
+	w0 := TestWriter{}
+	w1 := TestIncompleteWriter{}
+	mut mw := new_multi_writer(w0, w1)
+	n := mw.write('0123456789'.bytes()) or {
+		assert w0.bytes == '0123456789'.bytes()
+		assert w1.bytes == '012345678'.bytes()
+		return
+	}
+	assert false
+}
+
+fn test_multi_writer_write_error() {
+	w0 := TestWriter{}
+	w1 := TestErrorWriter{}
+	w2 := TestWriter{}
+	mut mw := new_multi_writer(w0, w1, w2)
+	n := mw.write('0123456789'.bytes()) or {
+		assert w0.bytes == '0123456789'.bytes()
+		assert w2.bytes == []
+		return
+	}
+	assert false
+}
+
+struct TestWriter {
+pub mut:
+	bytes []byte
+}
+
+fn (mut w TestWriter) write(buf []byte) ?int {
+	w.bytes << buf
+	return buf.len
+}
+
+struct TestIncompleteWriter {
+pub mut:
+	bytes []byte
+}
+
+fn (mut w TestIncompleteWriter) write(buf []byte) ?int {
+	b := buf[..buf.len - 1]
+	w.bytes << b
+	return b.len
+}
+
+struct TestErrorWriter {}
+
+fn (mut w TestErrorWriter) write(buf []byte) ?int {
+	return error('error writer errored')
+}