More cleanup, yey!

[python_utils.git] / dict_utils.py

diff --git a/dict_utils.py b/dict_utils.py
index 79c86edf286f2c9ea9983906385365199be74892..ecd23fda0fe0f4624a27ca6a8971dd068ce2958e 100644 (file)
--- a/dict_utils.py
+++ b/dict_utils.py
@@ -1,5 +1,7 @@
 #!/usr/bin/env python3
 
+"""Helper functions for dealing with dictionaries."""
+
 from itertools import islice
 from typing import Any, Callable, Dict, Iterator, List, Tuple
 
@@ -42,10 +44,10 @@ def shard(d: Dict[Any, Any], size: int) -> Iterator[Dict[Any, Any]]:
     """
     items = d.items()
     for x in range(0, len(d), size):
-        yield {key: value for (key, value) in islice(items, x, x + size)}
+        yield dict(islice(items, x, x + size))
 
 
-def coalesce_by_creating_list(key, new_value, old_value):
+def coalesce_by_creating_list(_, new_value, old_value):
     from list_utils import flatten
 
     return flatten([new_value, old_value])
@@ -55,11 +57,11 @@ def coalesce_by_creating_set(key, new_value, old_value):
     return set(coalesce_by_creating_list(key, new_value, old_value))
 
 
-def coalesce_last_write_wins(key, new_value, old_value):
+def coalesce_last_write_wins(_, new_value, discarded_old_value):
     return new_value
 
 
-def coalesce_first_write_wins(key, new_value, old_value):
+def coalesce_first_write_wins(_, discarded_new_value, old_value):
     return old_value
 
 
@@ -70,7 +72,7 @@ def raise_on_duplicated_keys(key, new_value, old_value):
 def coalesce(
     inputs: Iterator[Dict[Any, Any]],
     *,
-    aggregation_function: Callable[[Any, Any], Any] = coalesce_by_creating_list,
+    aggregation_function: Callable[[Any, Any, Any], Any] = coalesce_by_creating_list,
 ) -> Dict[Any, Any]:
     """Merge N dicts into one dict containing the union of all keys /
     values in the input dicts.  When keys collide, apply the
@@ -198,9 +200,7 @@ def min_key(d: Dict[Any, Any]) -> Any:
     return min(d.keys())
 
 
-def parallel_lists_to_dict(
-    keys: List[Any], values: List[Any]
-) -> Dict[Any, Any]:
+def parallel_lists_to_dict(keys: List[Any], values: List[Any]) -> Dict[Any, Any]:
     """Given two parallel lists (keys and values), create and return
     a dict.
 
@@ -211,9 +211,7 @@ def parallel_lists_to_dict(
 
     """
     if len(keys) != len(values):
-        raise Exception(
-            "Parallel keys and values lists must have the same length"
-        )
+        raise Exception("Parallel keys and values lists must have the same length")
     return dict(zip(keys, values))
 
 
@@ -227,7 +225,7 @@ def dict_to_key_value_lists(d: Dict[Any, Any]) -> Tuple[List[Any], List[Any]]:
     ['scott', '555-1212', '123 main st.', '12345']
 
     """
-    r = ([], [])
+    r: Tuple[List[Any], List[Any]] = ([], [])
     for (k, v) in d.items():
         r[0].append(k)
         r[1].append(v)