Enable ruff rule that enforces using items() to iterate over dict key/value pairs (#2811)

Author: bouweandela

esmvalcore/_recipe/check.py

@@ -329,13 +329,13 @@ def extract_shape(settings: dict[str, Any]) -> None:
         "crop": {True, False},
         "decomposed": {True, False},
     }
-    for key in valid:
+    for key, valid_values in valid.items():
         value = settings.get(key)
-        if not (value is None or value in valid[key]):
+        if not (value is None or value in valid_values):
             msg = (
                 f"In preprocessor function `extract_shape`: Invalid value "
                 f"'{value}' for argument '{key}', choose from "
-                "{}".format(", ".join(f"'{k}'".lower() for k in valid[key]))
+                "{}".format(", ".join(f"'{k}'".lower() for k in valid_values))
             )
             raise RecipeError(msg)
 

esmvalcore/_task.py

@@ -81,12 +81,12 @@ def _get_resource_usage(process, start_time, children=True):
                 processes = [process]
 
             # Update resource usage
-            for proc in cache:
+            for proc, cached_value in cache.items():
                 # Set cpu percent and memory usage to 0 for old processes
                 if proc not in processes:
-                    cache[proc][1] = 0
-                    cache[proc][2] = 0
-                    cache[proc][3] = 0
+                    cached_value[1] = 0
+                    cached_value[2] = 0
+                    cached_value[3] = 0
             for proc in processes:
                 # Update current processes
                 cache[proc] = [
@@ -206,9 +206,9 @@ def _ncl_type(value):
             int: "int64",
             dict: "logical",
         }
-        for type_ in typemap:
+        for type_, ncl_type in typemap.items():
             if isinstance(value, type_):
-                return typemap[type_]
+                return ncl_type
         msg = f"Unable to map {type(value)} to an NCL type"
         raise ValueError(msg)
 

esmvalcore/config/_diagnostics.py

@@ -164,9 +164,8 @@ def replace_tags_in_dict(self, dct: dict):
         Tags are updated one level deep, and only if the corresponding
         section exists in the ``TagsManager``.
         """
-        for key in dct:
+        for key, tags in dct.items():
             if key in self:
-                tags = dct[key]
                 dct[key] = self.get_tag_values(key, tags)
 
 

esmvalcore/dataset.py

@@ -69,9 +69,9 @@
 
 def _augment(base: dict, update: dict) -> None:
     """Update dict `base` with values from dict `update`."""
-    for key in update:
+    for key, value in update.items():
         if key not in base:
-            base[key] = update[key]
+            base[key] = value
 
 
 def _isglob(facet_value: FacetValue | None) -> bool:

esmvalcore/preprocessor/__init__.py

@@ -259,7 +259,7 @@ def _get_itype(step: str) -> str:
 
 def check_preprocessor_settings(settings: dict[str, Any]) -> None:
     """Check preprocessor settings."""
-    for step in settings:
+    for step, kwargs in settings.items():
         if step not in DEFAULT_ORDER:
             msg = (
                 f"Unknown preprocessor function '{step}', choose from: "
@@ -294,7 +294,7 @@ def check_preprocessor_settings(settings: dict[str, Any]) -> None:
             ],
         )
         if check_args:
-            invalid_args = set(settings[step]) - set(args)
+            invalid_args = set(kwargs) - set(args)
             if invalid_args:
                 msg = (
                     f"Invalid argument(s) [{', '.join(invalid_args)}] "
@@ -310,7 +310,7 @@ def check_preprocessor_settings(settings: dict[str, Any]) -> None:
             if p.default is not inspect.Parameter.empty
         ]
         end = None if not defaults else -len(defaults)
-        missing_args = set(args[:end]) - set(settings[step])
+        missing_args = set(args[:end]) - set(kwargs)
         if missing_args:
             msg = (
                 f"Missing required argument(s) {missing_args} for "
@@ -320,7 +320,7 @@ def check_preprocessor_settings(settings: dict[str, Any]) -> None:
 
         # Final sanity check in case the above fails to catch a mistake
         try:
-            signature.bind(None, **settings[step])
+            signature.bind(None, **kwargs)
         except TypeError:
             logger.error(
                 "Wrong preprocessor function arguments in function '%s'",

pyproject.toml

@@ -188,7 +188,6 @@ ignore = [
     "N818",     # Exception name should be named with an Error suffix
     "PERF",     # Use comprehensions
     "PGH003",   # Use specific rule codes when ignoring type issues
-    "PLC0206",  # Extracting value from dictionary without calling `.items()`
     "PLR2004",  # Don't use magic values
     "PLW2901",  # Don't overwrite a loop variable
     "PT009",    # Use a regular `assert` instead of unittest-style `assertListEqual`

tests/unit/config/test_config.py

@@ -205,8 +205,8 @@ def test_load_default_config(cfg_default, monkeypatch):
     assert all(hasattr(session, attr) for attr in directory_attrs)
 
     # Check default values
-    for key in default_cfg:
-        assert session[key] == default_cfg[key]
+    for key, value in default_cfg.items():
+        assert session[key] == value
 
     # Check output directories
     assert str(session.session_dir).startswith(

tests/unit/recipe/test_recipe.py

@@ -334,9 +334,9 @@ def test_update_multiproduct_multi_model_statistics():
     )
 
     for product in output:
-        for attr in common_attributes:
+        for attr, value in common_attributes.items():
             assert attr in product.attributes
-            assert product.attributes[attr] == common_attributes[attr]
+            assert product.attributes[attr] == value
         assert "alias" in product.attributes
         assert "dataset" in product.attributes
         assert "multi_model_statistics" in product.attributes
@@ -419,9 +419,9 @@ def test_update_multiproduct_no_timerange():
 
     assert product.filename == Path("/preproc/d/var/CMIP6_MultiModelMean.nc")
 
-    for attr in common_attributes:
+    for attr, value in common_attributes.items():
         assert attr in product.attributes
-        assert product.attributes[attr] == common_attributes[attr]
+        assert product.attributes[attr] == value
     assert "alias" in product.attributes
     assert "dataset" in product.attributes
     assert "multi_model_statistics" in product.attributes
@@ -523,9 +523,9 @@ def test_update_multiproduct_multi_model_statistics_percentile():
     )
 
     for product in output:
-        for attr in common_attributes:
+        for attr, value in common_attributes.items():
             assert attr in product.attributes
-            assert product.attributes[attr] == common_attributes[attr]
+            assert product.attributes[attr] == value
         assert "alias" in product.attributes
         assert "dataset" in product.attributes
         assert "multi_model_statistics" in product.attributes
@@ -617,9 +617,9 @@ def test_update_multiproduct_ensemble_statistics():
         "/preproc/d/var/CMIP6_CanESM2_EnsembleMedian_2000-2000.nc",
     )
 
-    for attr in common_attributes:
+    for attr, value in common_attributes.items():
         assert attr in product.attributes
-        assert product.attributes[attr] == common_attributes[attr]
+        assert product.attributes[attr] == value
     assert "alias" in product.attributes
     assert product.attributes["alias"] == "EnsembleMedian"
     assert "dataset" in product.attributes
@@ -704,9 +704,9 @@ def test_update_multiproduct_ensemble_statistics_percentile():
         "/preproc/d/var/CMIP6_CanESM2_EnsemblePercentile5_2000-2000.nc",
     )
 
-    for attr in common_attributes:
+    for attr, value in common_attributes.items():
         assert attr in product.attributes
-        assert product.attributes[attr] == common_attributes[attr]
+        assert product.attributes[attr] == value
     assert "alias" in product.attributes
     assert product.attributes["alias"] == "EnsemblePercentile5"
     assert "dataset" in product.attributes