Fix #56: stdout and stderr outputs in wrong order

4 files changed, 19 insertions, 3 deletions

diff --git a/scripts/.profile b/scripts/.profile
index 47ee141..73fbb28 100644
--- a/scripts/.profile
+++ b/scripts/.profile
@@ -17,5 +17,5 @@ nsjpy() {
     nsjail \
         --config "${NSJAIL_CFG:-/snekbox/snekbox.cfg}" \
         $nsj_args -- \
-        /snekbox/.venv/bin/python3 -Iq -c "$@"
+        /snekbox/.venv/bin/python3 -Iqu -c "$@"
 }
diff --git a/snekbox.cfg b/snekbox.cfg
index 4cb58de..1d58ea5 100644
--- a/snekbox.cfg
+++ b/snekbox.cfg
@@ -93,5 +93,5 @@ iface_no_lo: true
 
 exec_bin {
     path: "/snekbox/.venv/bin/python3"
-    arg: "-Iq"
+    arg: "-Iqu"
 }
diff --git a/snekbox/nsjail.py b/snekbox/nsjail.py
index 83d3b8d..df69e7a 100644
--- a/snekbox/nsjail.py
+++ b/snekbox/nsjail.py
@@ -128,7 +128,7 @@ class NsJail:
                 "--cgroup_pids_mount", str(CGROUP_PIDS_PARENT.parent),
                 "--cgroup_pids_parent", CGROUP_PIDS_PARENT.name,
                 "--",
-                self.python_binary, "-Iq", "-c", code
+                self.python_binary, "-Iqu", "-c", code
             )
 
             msg = "Executing code..."
diff --git a/tests/test_nsjail.py b/tests/test_nsjail.py
index f04d317..0b755b2 100644
--- a/tests/test_nsjail.py
+++ b/tests/test_nsjail.py
@@ -158,3 +158,19 @@ class NsJailTests(unittest.TestCase):
         self.assertEqual(result.returncode, 0)
         self.assertEqual(result.stdout, "")
         self.assertEqual(result.stderr, None)
+
+    def test_output_order(self):
+        stdout_msg = "greetings from stdout!"
+        stderr_msg = "hello from stderr!"
+        code = dedent(f"""
+            print({stdout_msg!r})
+            raise ValueError({stderr_msg!r})
+        """).strip()
+
+        result = self.nsjail.python3(code)
+        self.assertLess(
+            result.stdout.find(stdout_msg),
+            result.stdout.find(stderr_msg),
+            msg="stdout does not come before stderr"
+        )
+        self.assertEqual(result.stderr, None)