[3.14] gh-139065: Fix trailing space before long word in textwrap (GH-139070) (GH-139902)

Fix trailing space before a wrapped long word if the line length with
a space is exactly "width".
(cherry picked from commit 1c598e0436)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

Lib/textwrap.py

@@ -211,7 +211,7 @@ def _handle_long_word(self, reversed_chunks, cur_line, cur_len, width):
 
         # If we're allowed to break long words, then do so: put as much
         # of the next chunk onto the current line as will fit.
-        if self.break_long_words:
+        if self.break_long_words and space_left > 0:
             end = space_left
             chunk = reversed_chunks[-1]
             if self.break_on_hyphens and len(chunk) > space_left:

Misc/NEWS.d/next/Library/2025-09-17-19-08-34.gh-issue-139065.Hu8fM5.rst

@@ -0,0 +1,2 @@
+Fix trailing space before a wrapped long word if the line length is exactly
+*width* in :mod:`textwrap`.