REF: combine IndexEngine test files (#31193)

Author: jbrockmendel

pandas/tests/indexes/test_engines.py

@@ -1,8 +1,31 @@
 import re
 
+import numpy as np
 import pytest
 
+from pandas._libs import algos as libalgos, index as libindex
+
 import pandas as pd
+import pandas._testing as tm
+
+
+@pytest.fixture(
+    params=[
+        (libindex.Int64Engine, np.int64),
+        (libindex.Int32Engine, np.int32),
+        (libindex.Int16Engine, np.int16),
+        (libindex.Int8Engine, np.int8),
+        (libindex.UInt64Engine, np.uint64),
+        (libindex.UInt32Engine, np.uint32),
+        (libindex.UInt16Engine, np.uint16),
+        (libindex.UInt8Engine, np.uint8),
+        (libindex.Float64Engine, np.float64),
+        (libindex.Float32Engine, np.float32),
+    ],
+    ids=lambda x: x[0].__name__,
+)
+def numeric_indexing_engine_type_and_dtype(request):
+    return request.param
 
 
 class TestDatetimeEngine:
@@ -55,3 +78,161 @@ def test_not_contains_requires_timestamp(self, scalar):
 
             with pytest.raises(KeyError, match=msg):
                 tdi._engine.get_loc(scalar)
+
+
+class TestNumericEngine:
+    def test_is_monotonic(self, numeric_indexing_engine_type_and_dtype):
+        engine_type, dtype = numeric_indexing_engine_type_and_dtype
+        num = 1000
+        arr = np.array([1] * num + [2] * num + [3] * num, dtype=dtype)
+
+        # monotonic increasing
+        engine = engine_type(lambda: arr, len(arr))
+        assert engine.is_monotonic_increasing is True
+        assert engine.is_monotonic_decreasing is False
+
+        # monotonic decreasing
+        engine = engine_type(lambda: arr[::-1], len(arr))
+        assert engine.is_monotonic_increasing is False
+        assert engine.is_monotonic_decreasing is True
+
+        # neither monotonic increasing or decreasing
+        arr = np.array([1] * num + [2] * num + [1] * num, dtype=dtype)
+        engine = engine_type(lambda: arr[::-1], len(arr))
+        assert engine.is_monotonic_increasing is False
+        assert engine.is_monotonic_decreasing is False
+
+    def test_is_unique(self, numeric_indexing_engine_type_and_dtype):
+        engine_type, dtype = numeric_indexing_engine_type_and_dtype
+
+        # unique
+        arr = np.array([1, 3, 2], dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+        assert engine.is_unique is True
+
+        # not unique
+        arr = np.array([1, 2, 1], dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+        assert engine.is_unique is False
+
+    def test_get_loc(self, numeric_indexing_engine_type_and_dtype):
+        engine_type, dtype = numeric_indexing_engine_type_and_dtype
+
+        # unique
+        arr = np.array([1, 2, 3], dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+        assert engine.get_loc(2) == 1
+
+        # monotonic
+        num = 1000
+        arr = np.array([1] * num + [2] * num + [3] * num, dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+        assert engine.get_loc(2) == slice(1000, 2000)
+
+        # not monotonic
+        arr = np.array([1, 2, 3] * num, dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+        expected = np.array([False, True, False] * num, dtype=bool)
+        result = engine.get_loc(2)
+        assert (result == expected).all()
+
+    def test_get_backfill_indexer(self, numeric_indexing_engine_type_and_dtype):
+        engine_type, dtype = numeric_indexing_engine_type_and_dtype
+
+        arr = np.array([1, 5, 10], dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+
+        new = np.arange(12, dtype=dtype)
+        result = engine.get_backfill_indexer(new)
+
+        expected = libalgos.backfill(arr, new)
+        tm.assert_numpy_array_equal(result, expected)
+
+    def test_get_pad_indexer(self, numeric_indexing_engine_type_and_dtype):
+        engine_type, dtype = numeric_indexing_engine_type_and_dtype
+
+        arr = np.array([1, 5, 10], dtype=dtype)
+        engine = engine_type(lambda: arr, len(arr))
+
+        new = np.arange(12, dtype=dtype)
+        result = engine.get_pad_indexer(new)
+
+        expected = libalgos.pad(arr, new)
+        tm.assert_numpy_array_equal(result, expected)
+
+
+class TestObjectEngine:
+    engine_type = libindex.ObjectEngine
+    dtype = np.object_
+    values = list("abc")
+
+    def test_is_monotonic(self):
+
+        num = 1000
+        arr = np.array(["a"] * num + ["a"] * num + ["c"] * num, dtype=self.dtype)
+
+        # monotonic increasing
+        engine = self.engine_type(lambda: arr, len(arr))
+        assert engine.is_monotonic_increasing is True
+        assert engine.is_monotonic_decreasing is False
+
+        # monotonic decreasing
+        engine = self.engine_type(lambda: arr[::-1], len(arr))
+        assert engine.is_monotonic_increasing is False
+        assert engine.is_monotonic_decreasing is True
+
+        # neither monotonic increasing or decreasing
+        arr = np.array(["a"] * num + ["b"] * num + ["a"] * num, dtype=self.dtype)
+        engine = self.engine_type(lambda: arr[::-1], len(arr))
+        assert engine.is_monotonic_increasing is False
+        assert engine.is_monotonic_decreasing is False
+
+    def test_is_unique(self):
+        # unique
+        arr = np.array(self.values, dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+        assert engine.is_unique is True
+
+        # not unique
+        arr = np.array(["a", "b", "a"], dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+        assert engine.is_unique is False
+
+    def test_get_loc(self):
+        # unique
+        arr = np.array(self.values, dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+        assert engine.get_loc("b") == 1
+
+        # monotonic
+        num = 1000
+        arr = np.array(["a"] * num + ["b"] * num + ["c"] * num, dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+        assert engine.get_loc("b") == slice(1000, 2000)
+
+        # not monotonic
+        arr = np.array(self.values * num, dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+        expected = np.array([False, True, False] * num, dtype=bool)
+        result = engine.get_loc("b")
+        assert (result == expected).all()
+
+    def test_get_backfill_indexer(self):
+        arr = np.array(["a", "e", "j"], dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+
+        new = np.array(list("abcdefghij"), dtype=self.dtype)
+        result = engine.get_backfill_indexer(new)
+
+        expected = libalgos.backfill["object"](arr, new)
+        tm.assert_numpy_array_equal(result, expected)
+
+    def test_get_pad_indexer(self):
+        arr = np.array(["a", "e", "j"], dtype=self.dtype)
+        engine = self.engine_type(lambda: arr, len(arr))
+
+        new = np.array(list("abcdefghij"), dtype=self.dtype)
+        result = engine.get_pad_indexer(new)
+
+        expected = libalgos.pad["object"](arr, new)
+        tm.assert_numpy_array_equal(result, expected)