Update.

test/tempfile/named_temporary_file_no_delete.wren

@@ -0,0 +1,18 @@
+// retoor <retoor@molodetz.nl>
+
+import "tempfile" for NamedTemporaryFile
+import "io" for File
+import "pathlib" for Path
+
+var tmp = NamedTemporaryFile.new("", "tmp", null, false)
+System.print(tmp.delete) // expect: false
+
+tmp.write("persistent")
+tmp.close()
+System.print(tmp.closed) // expect: true
+System.print(Path.new(tmp.name).exists()) // expect: true
+
+var content = File.read(tmp.name)
+System.print(content) // expect: persistent
+
+File.delete(tmp.name)