128-revival-add-more-tests (#132)

* Fixed docstring

* Renamed test_structure -> test_coverage

* Fixed bug in test_coverage

* WIP Refactoring

* xfail coverage test

* Add tests base

* Add more test prototypes to test_base

* Add tests for Search and SearchMeta

* Add accumulator test

Author: VianneyMI

src/monggregate/operators/accumulators/accumulator.py

@@ -16,7 +16,7 @@
 class AccumulatorEnum(StrEnum):
     """Enumeration of available accumulators"""
 
-    ACCUMULATOR ="$accumulator"
+    ACCUMULATOR = "$accumulator"
     ADD_TO_SET = "$addToSet"
     AVG = "$avg"
     BOTTOM = "$bottom"
@@ -37,11 +37,13 @@ class AccumulatorEnum(StrEnum):
     TOP = "$top"
     TOP_N = "$topN"
 
+
 # Classes
 # -----------------------------------------
 class Accumulator(Operator, ABC):
     """Base class for accumulators"""
 
+
 # Type aliases
 # -----------------------------------------
 AccumulatorExpression = dict[AccumulatorEnum, Any]