Fix UTextWrapper trailing whitespace handling

breezy/utextwrap.py

@@ -23,6 +23,7 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 
+import sys
 import textwrap
 from unicodedata import east_asian_width as _eawidth
 
@@ -212,8 +213,16 @@ def _wrap_chunks(self, chunks):
                 cur_len = sum(map(len, cur_line))
 
             # If the last chunk on this line is all whitespace, drop it.
-            if self.drop_whitespace and cur_line and not cur_line[-1].strip():
-                del cur_line[-1]
+            # Python 3.13+ uses a while loop to drop multiple trailing whitespace chunks
+            # Python < 3.13 uses an if statement to drop only one trailing whitespace chunk
+            if sys.version_info >= (3, 13):
+                while self.drop_whitespace and cur_line and cur_line[-1].strip() == "":
+                    cur_len -= len(cur_line[-1])
+                    del cur_line[-1]
+            else:
+                if self.drop_whitespace and cur_line and cur_line[-1].strip() == "":
+                    cur_len -= len(cur_line[-1])
+                    del cur_line[-1]
 
             # Convert current line back to a string and store it in list
             # of all lines (return value).

doc/en/release-notes/brz-3.3.txt

@@ -5,6 +5,13 @@ Breezy Release Notes
 .. toctree::
    :maxdepth: 1
 
+brz 3.3.20
+##########
+
+ * Fix ``UTextWrapper`` to properly drop trailing whitespace when wrapping
+   long words, matching Python 3.13's ``textwrap`` behavior.
+   (Jelmer Vernooij)
+
 brz 3.3.19
 ##########