bpo-30754: Document textwrap.dedent blank line behavior. (GH-14469)
* Added documentation for textwrap.dedent behavior.
* Remove an obsolete note about pre-2.5 behavior from the docstring.
(cherry picked from commit eb97b9211e7c99841d6cae8c63893b3525d5a401)
Co-authored-by: tmblweed <tmblweed@users.noreply.github.com>
diff --git a/Doc/library/textwrap.rst b/Doc/library/textwrap.rst
index d254466..0f11ef4 100644
--- a/Doc/library/textwrap.rst
+++ b/Doc/library/textwrap.rst
@@ -77,6 +77,9 @@
equal: the lines ``" hello"`` and ``"\thello"`` are considered to have no
common leading whitespace.
+ Lines containing only whitespace are ignored in the input and normalized to a
+ single newline character in the output.
+
For example::
def test():
diff --git a/Lib/textwrap.py b/Lib/textwrap.py
index 8103f34..30e693c 100644
--- a/Lib/textwrap.py
+++ b/Lib/textwrap.py
@@ -420,9 +420,9 @@
Note that tabs and spaces are both treated as whitespace, but they
are not equal: the lines " hello" and "\\thello" are
- considered to have no common leading whitespace. (This behaviour is
- new in Python 2.5; older versions of this module incorrectly
- expanded tabs before searching for common leading whitespace.)
+ considered to have no common leading whitespace.
+
+ Entirely blank lines are normalized to a newline character.
"""
# Look for the longest leading string of spaces and tabs common to
# all lines.