REF: IntervalIndex.equals defer to IntervalArray.equals (pandas-dev#3…

…6871)

pandas/core/arrays/_mixins.py

@@ -8,7 +8,9 @@
 from pandas.util._decorators import cache_readonly, doc
 from pandas.util._validators import validate_fillna_kwargs
 
+from pandas.core.dtypes.common import is_dtype_equal
 from pandas.core.dtypes.inference import is_array_like
+from pandas.core.dtypes.missing import array_equivalent
 
 from pandas.core import missing
 from pandas.core.algorithms import take, unique
@@ -115,6 +117,13 @@ def T(self: _T) -> _T:
 
     # ------------------------------------------------------------------------
 
+    def equals(self, other) -> bool:
+        if type(self) is not type(other):
+            return False
+        if not is_dtype_equal(self.dtype, other.dtype):
+            return False
+        return bool(array_equivalent(self._ndarray, other._ndarray))
+
     def _values_for_argsort(self):
         return self._ndarray
 

pandas/core/arrays/interval.py

@@ -706,6 +706,16 @@ def astype(self, dtype, copy=True):
             msg = f"Cannot cast {type(self).__name__} to dtype {dtype}"
             raise TypeError(msg) from err
 
+    def equals(self, other) -> bool:
+        if type(self) != type(other):
+            return False
+
+        return bool(
+            self.closed == other.closed
+            and self.left.equals(other.left)
+            and self.right.equals(other.right)
+        )
+
     @classmethod
     def _concat_same_type(cls, to_concat):
         """

pandas/core/indexes/interval.py

@@ -997,19 +997,10 @@ def equals(self, other: object) -> bool:
         if self.is_(other):
             return True
 
-        # if we can coerce to an IntervalIndex then we can compare
         if not isinstance(other, IntervalIndex):
-            if not is_interval_dtype(other):
-                return False
-            other = Index(other)
-            if not isinstance(other, IntervalIndex):
-                return False
+            return False
 
-        return (
-            self.left.equals(other.left)
-            and self.right.equals(other.right)
-            and self.closed == other.closed
-        )
+        return self._data.equals(other._data)
 
     # --------------------------------------------------------------------
     # Set Operations