fix: preserve blank lines with body length limit

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

#2079

Author: schlotter

commitizen/commands/commit.py

@@ -120,9 +120,10 @@ def _wrap_body(self, message: str) -> str:
         if len(lines) < 3:
             return message
 
-        # First line is subject, second is blank line, rest are body lines
+        # Preserve intentional blank lines while wrapping non-empty body lines.
         wrapped_body_lines = chain.from_iterable(
-            textwrap.wrap(line, width=body_length_limit) for line in lines[2:]
+            textwrap.wrap(line, width=body_length_limit) if line else [line]
+            for line in lines[2:]
         )
         return "\n".join(chain(lines[:2], wrapped_body_lines))
 

tests/commands/test_commit_command.py

@@ -390,6 +390,11 @@ def test_commit_command_with_config_message_length_limit(
             100,
             id="preserves_line_breaks",
         ),
+        pytest.param(
+            "Line1 is shorter than the limit but has paragraph break\n\nLine2 stays in a separate paragraph",
+            100,
+            id="preserves_blank_lines",
+        ),
         pytest.param(
             "This is a very long line that exceeds 72 characters and should NOT be wrapped when body_length_limit is set to 0",
             0,

tests/commands/test_commit_command/test_commit_command_body_length_limit_preserves_blank_lines_.txt

@@ -0,0 +1,5 @@
+feat: add feature
+
+Line1 is shorter than the limit but has paragraph break
+
+Line2 stays in a separate paragraph