[Backport version-14.6] Match numeric suffixes only in experiment names

Match numeric suffixes only in experiment names

Prevents crashes when names like 'es_mda_adaptive' exist

(cherry picked from commit 1485aa7)

Co-authored-by: Feda Curic <feda.curic@gmail.com>

Author: scout-team-app[bot]

src/ert/storage/local_storage.py

@@ -4,6 +4,7 @@
 import json
 import logging
 import os
+import re
 import shutil
 from collections.abc import Generator, MutableSequence
 from datetime import datetime
@@ -546,21 +547,17 @@ def get_unique_experiment_name(self, experiment_name: str) -> str:
         if experiment_name not in [e.name for e in self.experiments]:
             return experiment_name
 
-        if (
-            len(
-                same_prefix := [
-                    e.name
-                    for e in self.experiments
-                    if e.name.startswith(experiment_name + "_")
-                ]
-            )
-            > 0
-        ):
-            return (
-                experiment_name
-                + "_"
-                + str(max(int(e[e.rfind("_") + 1 :]) for e in same_prefix) + 1)
-            )
+        # Only match names that follow the pattern: experiment_name_<digits>
+        pattern = re.escape(experiment_name) + r"_(\d+)$"
+
+        numeric_suffixes = []
+        for e in self.experiments:
+            match = re.match(pattern, e.name)
+            if match:
+                numeric_suffixes.append(int(match.group(1)))
+
+        if numeric_suffixes:
+            return experiment_name + "_" + str(max(numeric_suffixes) + 1)
         else:
             return experiment_name + "_0"
 

tests/ert/unit_tests/storage/test_local_storage.py

@@ -476,6 +476,25 @@ def test_get_unique_experiment_name(snake_oil_storage):
         assert snake_oil_storage.get_unique_experiment_name("") == "default_0"
 
 
+def test_get_unique_experiment_name_ignores_non_numeric_suffixes(tmp_path):
+    """
+    Regression test for bug where non-numeric suffixes caused ValueError.
+
+    When an experiment like 'es_mda_adaptive' existed, attempting to generate
+    a unique name for 'es_mda' would incorrectly try to parse 'adaptive' as
+    an integer, causing: ValueError: invalid literal for int() with base 10: 'adaptive'
+
+    The fix ensures only numeric suffixes (e.g., 'es_mda_0', 'es_mda_1') are
+    considered when generating new unique names.
+    """
+    with open_storage(tmp_path, mode="w") as storage:
+        storage.create_experiment(name="es_mda")
+        storage.create_experiment(name="es_mda_adaptive")
+
+        # Should return es_mda_0, not crash on "adaptive"
+        assert storage.get_unique_experiment_name("es_mda") == "es_mda_0"
+
+
 def add_to_name(prefix: str):
     def _inner(params):
         for param in params: