From 9c99a4be4c3368fddad9b29864d29827bdfdff80 Mon Sep 17 00:00:00 2001
From: Leon Lan <30997278+leonlan@users.noreply.github.com>
Date: Mon, 24 Jun 2024 20:21:31 +0200
Subject: [PATCH] Raise when data is both specification and section (#120)

---
 tests/parse/test_parse_vrplib.py | 19 +++++++++++++++++++
 vrplib/parse/parse_vrplib.py     |  6 ++++++
 2 files changed, 25 insertions(+)

diff --git a/tests/parse/test_parse_vrplib.py b/tests/parse/test_parse_vrplib.py
index e30c24a1..01dae71a 100644
--- a/tests/parse/test_parse_vrplib.py
+++ b/tests/parse/test_parse_vrplib.py
@@ -231,6 +231,25 @@ def test_parse_vrplib_do_not_compute_edge_weights():
     assert_("edge_weight" not in actual)
 
 
+def test_parse_vrplib_raises_data_specification_and_section():
+    """
+    Tests that a ValueError is raised when data is included both as
+    specification and section.
+    """
+    instance = "\n".join(
+        [
+            "SERVICE_TIME: 10",
+            "SERVICE_TIME_SECTION",
+            "1    20",
+            "2    20",
+        ]
+    )
+
+    # Service time is both a specification and a section which is not allowed.
+    with assert_raises(ValueError):
+        parse_vrplib(instance)
+
+
 def test_empty_text():
     """
     Tests if an empty text file is still read correctly.
diff --git a/vrplib/parse/parse_vrplib.py b/vrplib/parse/parse_vrplib.py
index 6fd6de8b..546b2244 100644
--- a/vrplib/parse/parse_vrplib.py
+++ b/vrplib/parse/parse_vrplib.py
@@ -43,6 +43,12 @@ def parse_vrplib(text: str, compute_edge_weights: bool = True) -> Instance:
 
     for section in sections:
         section_name, data = parse_section(section, instance)
+
+        if section_name in instance:
+            name = section_name.upper()
+            msg = f"'{name}' is used both as a specification and a section."
+            raise ValueError(msg)
+
         instance[section_name] = data  # type: ignore
 
     if instance and compute_edge_weights and "edge_weight" not in instance: