From 0a28d2898f92af4159c13af8a5c9488a0f9d766c Mon Sep 17 00:00:00 2001
From: Mithilesh Lohar <128236295+mithlohar144@users.noreply.github.com>
Date: Mon, 30 Mar 2026 09:51:01 +0530
Subject: [PATCH 1/2] fix: validate plot_congestion.py CLI arguments

Signed-off-by: Mithilesh Lohar <128236295+mithlohar144@users.noreply.github.com>
---
 flow/util/plot_congestion.py | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/flow/util/plot_congestion.py b/flow/util/plot_congestion.py
index dfa0e600a1..af36b02554 100644
--- a/flow/util/plot_congestion.py
+++ b/flow/util/plot_congestion.py
@@ -4,9 +4,29 @@
 import re
 import os
 
+def usage(script):
+    print(
+        f"Usage: {script} <sweep_name> <output_png> <congestion_file...> <sweep_value...>",
+        file=sys.stderr,
+    )
+    print(
+        "Provide an even number of trailing arguments split equally between files and values.",
+        file=sys.stderr,
+    )
+
+
+if len(sys.argv) < 5:
+    usage(sys.argv[0])
+    sys.exit(2)
+
 sweep = sys.argv[1]
 output = sys.argv[2]
 remainder = sys.argv[3:]
+if len(remainder) % 2 != 0:
+    print("Error: trailing arguments must be an even count.", file=sys.stderr)
+    usage(sys.argv[0])
+    sys.exit(2)
+
 files = remainder[: len(remainder) // 2]
 values = remainder[len(remainder) // 2 :]
 

From e607af319f53b0515d915133c87a024190f1f9a0 Mon Sep 17 00:00:00 2001
From: Mithilesh Lohar <128236295+mithlohar144@users.noreply.github.com>
Date: Mon, 30 Mar 2026 21:05:15 +0530
Subject: [PATCH 2/2] Format plot_congestion.py with black

Signed-off-by: Mithilesh Lohar <128236295+mithlohar144@users.noreply.github.com>
---
 flow/util/plot_congestion.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/flow/util/plot_congestion.py b/flow/util/plot_congestion.py
index af36b02554..87413a26b3 100644
--- a/flow/util/plot_congestion.py
+++ b/flow/util/plot_congestion.py
@@ -4,6 +4,7 @@
 import re
 import os
 
+
 def usage(script):
     print(
         f"Usage: {script} <sweep_name> <output_png> <congestion_file...> <sweep_value...>",