Merge pull request #8 from warsaw/issue3

Docstrings can be a single line #8

Module docstrings always start in column zero.  If they don't I don't care 😄 .  That doesn't necessarily mean this heuristic won't false positive for other non-module docstrings in column 0, but for now, let's call it good enough.  Until it's not.

blue/__init__.py

@@ -25,11 +25,6 @@
 def is_docstring(leaf: Leaf) -> bool:
     # Most of this function was copied from Black!
 
-    if not is_multiline_string(leaf):
-        # For the purposes of docstring re-indentation, we don't need to do anything
-        # with single-line docstrings.
-        return False
-
     if prev_siblings_are(
         leaf.parent, [None, token.NEWLINE, token.INDENT, syms.simple_stmt]
     ):
@@ -41,7 +36,7 @@ def is_docstring(leaf: Leaf) -> bool:
         # grammar. We're safe to return True without further checks.
         return True
 
-    if leaf.parent.prev_sibling is None:
+    if leaf.parent.prev_sibling is None and leaf.column == 0:
         # Identify module docstrings.
         return True