DOC: Add whatsnew note of PeriodIndex.truncate bug

Licht-T · Licht-T · commit 7c1f2f3792b1 · 2017-10-29T13:43:22.000+09:00
diff --git a/doc/source/whatsnew/v0.22.0.txt b/doc/source/whatsnew/v0.22.0.txt
@@ -96,7 +96,7 @@ Conversion
 Indexing
 ^^^^^^^^
 
--
+- Bug in :func:`PeriodIndex.truncate` which raises ``TypeError`` when ``PeriodIndex`` is monotonic (:issue:`17717`)
 -
 -
 

Original file line number	Diff line number	Diff line change
`@@ -96,7 +96,7 @@ Conversion`
`96`	`96`	`Indexing`
`97`	`97`	`^^^^^^^^`
`98`	`98`
`99`		`--`
	`99`	+- Bug in :func:`PeriodIndex.truncate` which raises ``TypeError`` when ``PeriodIndex`` is monotonic (:issue:`17717`)
`100`	`100`	`-`
`101`	`101`	`-`
`102`	`102`