From ea6b801209d957cd95fc579e394db47cb1b289e3 Mon Sep 17 00:00:00 2001 From: csaoma Date: Thu, 16 Apr 2020 20:43:39 -0400 Subject: [PATCH] 'change' --- pandas/core/reshape/merge.py | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/pandas/core/reshape/merge.py b/pandas/core/reshape/merge.py index 607a1b75dcfcd..e3f4a80ecce7c 100644 --- a/pandas/core/reshape/merge.py +++ b/pandas/core/reshape/merge.py @@ -1727,20 +1727,19 @@ def flip(xs) -> np.ndarray: tolerance = self.tolerance # we require sortedness and non-null values in the join keys - msg_sorted = "{side} keys must be sorted" - msg_missings = "Merge keys contain null values on {side} side" - if not Index(left_values).is_monotonic: + side = "left" if isna(left_values).any(): - raise ValueError(msg_missings.format(side="left")) + raise ValueError(f"Merge keys contain null values on {side} side") else: - raise ValueError(msg_sorted.format(side="left")) + raise ValueError(f"{side} keys must be sorted") if not Index(right_values).is_monotonic: + side = "right" if isna(right_values).any(): - raise ValueError(msg_missings.format(side="right")) + raise ValueError(f"Merge keys contain null values on {side} side") else: - raise ValueError(msg_sorted.format(side="right")) + raise ValueError(f"{side} keys must be sorted") # initial type conversion as needed if needs_i8_conversion(left_values):