Add logging of duplicate gen_kw parameter names

src/ert/config/ensemble_config.py

@@ -56,6 +56,9 @@ def __post_init__(self) -> None:
             [p.name for p in self.parameter_configs.values()],
             [key for config in self.response_configs.values() for key in config.keys],
         )
+        self._check_for_duplicate_gen_kw_param_names(
+            [p for p in self.parameter_configs.values() if isinstance(p, GenKwConfig)]
+        )
 
         self.grid_file = _get_abs_path(self.grid_file)
 
@@ -73,6 +76,23 @@ def _check_for_duplicate_names(
                 duplicate_names[0],
             )
 
+    @staticmethod
+    def _check_for_duplicate_gen_kw_param_names(gen_kw_list: list[GenKwConfig]) -> None:
+        gen_kw_param_count = Counter(
+            keyword.name for p in gen_kw_list for keyword in p.transform_functions
+        )
+        duplicate_gen_kw_names = [
+            (n, c) for n, c in gen_kw_param_count.items() if c > 1
+        ]
+
+        if duplicate_gen_kw_names:
+            duplicates_formatted = ", ".join(
+                f"{name}({count})" for name, count in duplicate_gen_kw_names
+            )
+            logger.info(
+                f"Found duplicate GEN_KW parameter names: {duplicates_formatted}"
+            )
+
     @no_type_check
     @classmethod
     def from_dict(cls, config_dict: ConfigDict) -> EnsembleConfig:

tests/ert/unit_tests/config/test_ensemble_config.py

@@ -1,3 +1,4 @@
+import logging
 import os
 from datetime import datetime
 from pathlib import Path
@@ -162,3 +163,31 @@ def test_that_empty_grid_file_raises(tmpdir):
             match="did not contain dimensions",
         ):
             _ = ErtConfig.from_file("config.ert")
+
+
+@pytest.mark.usefixtures("use_tmpdir")
+def test_logging_of_duplicate_gen_kw_parameter_names(caplog):
+    Path("MULTFLT1.TXT").write_text("a UNIFORM 0 1\nc UNIFORM 2 5", encoding="utf-8")
+    Path("MULTFLT2.TXT").write_text("a UNIFORM 0 1\nc UNIFORM 4 7", encoding="utf-8")
+    Path("FAULT_TEMPLATE").write_text("", encoding="utf-8")
+    config_dict = {
+        ConfigKeys.GEN_KW: [
+            [
+                "test_group1",
+                "FAULT_TEMPLATE",
+                "MULTFLT.INC",
+                "MULTFLT1.TXT",
+                "FORWARD_INIT:FALSE",
+            ],
+            [
+                "test_group2",
+                "FAULT_TEMPLATE",
+                "MULTFLT.INC",
+                "MULTFLT2.TXT",
+                "FORWARD_INIT:FALSE",
+            ],
+        ],
+    }
+    with caplog.at_level(logging.INFO):
+        EnsembleConfig.from_dict(config_dict=config_dict)
+    assert "Found duplicate GEN_KW parameter names: a(2), c(2)" in caplog.text