fix ArrayManager.diff

jbrockmendel · jbrockmendel · commit 657708bd801d · 2022-09-08T15:35:09.000-07:00
diff --git a/pandas/core/internals/array_manager.py b/pandas/core/internals/array_manager.py
@@ -363,8 +363,7 @@ def putmask(self: T, mask, new, align: bool = True) -> T:
         )
 
     def diff(self: T, n: int, axis: int) -> T:
-        axis = self._normalize_axis(axis)
-        # Only reached with self.ndim == 2 and (normalized) axis == 0
+        assert self.ndim == 2 and axis == 0  # caller ensures
         return self.apply(algos.diff, n=n, axis=axis)
 
     def interpolate(self: T, **kwargs) -> T:

Original file line number	Diff line number	Diff line change
`@@ -363,8 +363,7 @@ def putmask(self: T, mask, new, align: bool = True) -> T:`
`363`	`363`	`)`
`364`	`364`
`365`	`365`	`def diff(self: T, n: int, axis: int) -> T:`
`366`		`- axis = self._normalize_axis(axis)`
`367`		`- # Only reached with self.ndim == 2 and (normalized) axis == 0`
	`366`	`+ assert self.ndim == 2 and axis == 0 # caller ensures`
`368`	`367`	`return self.apply(algos.diff, n=n, axis=axis)`
`369`	`368`
`370`	`369`	`def interpolate(self: T, **kwargs) -> T:`