Paper over the differences in newline and indent of docstrings between Python versions

Author: clayote

src/attr/_make.py

@@ -10,6 +10,7 @@
 import itertools
 import linecache
 import sys
+import textwrap
 import types
 import unicodedata
 import weakref
@@ -567,17 +568,21 @@ def _make_cached_property_uncached(original_cached_property_func, cls):
     doc = original_cached_property_func.__doc__
     doc_lines = []
     if doc is not None:
-        doc_lines = doc.splitlines(True)
+        doc_lines = doc.splitlines()
         if len(doc_lines) == 1:
             doc_lines = ['    """' + doc_lines[0] + '"""']
         else:
-            doc_lines[0] = '    """' + doc_lines[0].rstrip()
+            line0 = '    """' + doc_lines[0].strip()
             for i, line in enumerate(doc_lines[1:], start=1):
-                if line.strip():
-                    doc_lines[i] = "    " + line.rstrip()
+                line = line.strip()
+                if line:
+                    doc_lines[i] = "    " + line
                 else:
-                    doc_lines[i] = line.rstrip()
-            doc_lines.append('    """')
+                    doc_lines[i] = ""
+            if len(doc_lines) > 2 and doc_lines[-2] == doc_lines[-1] == "":
+                doc_lines = [line0] + doc_lines[1:-1] + ['    """']
+            else:
+                doc_lines = [line0] + doc_lines[1:] + ['    """']
 
     annotation = inspect.signature(
         original_cached_property_func

tests/test_slots.py

@@ -788,10 +788,9 @@ def f(self):
             """
             return self.x
 
-    assert (
-        textwrap.dedent(A.f.__doc__)
-        == """This function is so well documented,\n\nI had to put newlines in\n\n"""
-    )
+    docstring_lines = A.f.__doc__.splitlines()
+    docstring_lines_dedented = [line.lstrip() for line in docstring_lines]
+    assert docstring_lines_dedented[:4] == ["This function is so well documented,", "", "I had to put newlines in", ""]
 
 
 def test_slots_cached_property_class_does_not_have__dict__():