Remove blank lines before class docstring (#3692)

[etc/vim.git] / src / black / lines.py

diff --git a/src/black/lines.py b/src/black/lines.py
index 66bba14b357166eb984dcba459689aaf3eb87142..daf0444d24e9a7d57c86f290344323fc7397f775 100644 (file)
--- a/src/black/lines.py
+++ b/src/black/lines.py
@@ -33,6 +33,7 @@ from black.nodes import (
     syms,
     whitespace,
 )
+from black.strings import str_width
 from blib2to3.pgen2 import token
 from blib2to3.pytree import Leaf, Node
 
@@ -521,7 +522,7 @@ class EmptyLineTracker:
     mode: Mode
     previous_line: Optional[Line] = None
     previous_block: Optional[LinesBlock] = None
-    previous_defs: List[int] = field(default_factory=list)
+    previous_defs: List[Line] = field(default_factory=list)
     semantic_leading_comment: Optional[LinesBlock] = None
 
     def maybe_empty_lines(self, current_line: Line) -> LinesBlock:
@@ -577,12 +578,18 @@ class EmptyLineTracker:
         else:
             before = 0
         depth = current_line.depth
-        while self.previous_defs and self.previous_defs[-1] >= depth:
+        while self.previous_defs and self.previous_defs[-1].depth >= depth:
             if self.mode.is_pyi:
                 assert self.previous_line is not None
                 if depth and not current_line.is_def and self.previous_line.is_def:
                     # Empty lines between attributes and methods should be preserved.
                     before = min(1, before)
+                elif (
+                    Preview.blank_line_after_nested_stub_class in self.mode
+                    and self.previous_defs[-1].is_class
+                    and not self.previous_defs[-1].is_stub_class
+                ):
+                    before = 1
                 elif depth:
                     before = 0
                 else:
@@ -592,7 +599,7 @@ class EmptyLineTracker:
                     before = 1
                 elif (
                     not depth
-                    and self.previous_defs[-1]
+                    and self.previous_defs[-1].depth
                     and current_line.leaves[-1].type == token.COLON
                     and (
                         current_line.leaves[0].value
@@ -627,6 +634,8 @@ class EmptyLineTracker:
             and self.previous_line.is_class
             and current_line.is_triple_quoted_string
         ):
+            if Preview.no_blank_line_before_class_docstring in current_line.mode:
+                return 0, 1
             return before, 1
 
         if self.previous_line and self.previous_line.opens_block:
@@ -637,7 +646,7 @@ class EmptyLineTracker:
         self, current_line: Line, before: int
     ) -> Tuple[int, int]:
         if not current_line.is_decorator:
-            self.previous_defs.append(current_line.depth)
+            self.previous_defs.append(current_line)
         if self.previous_line is None:
             # Don't insert empty lines before the first line in the file.
             return 0, 0
@@ -753,9 +762,11 @@ def is_line_short_enough(  # noqa: C901
     if not line_str:
         line_str = line_to_string(line)
 
+    width = str_width if mode.preview else len
+
     if Preview.multiline_string_handling not in mode:
         return (
-            len(line_str) <= mode.line_length
+            width(line_str) <= mode.line_length
             and "\n" not in line_str  # multiline strings
             and not line.contains_standalone_comments()
         )
@@ -764,10 +775,10 @@ def is_line_short_enough(  # noqa: C901
         return False
     if "\n" not in line_str:
         # No multiline strings (MLS) present
-        return len(line_str) <= mode.line_length
+        return width(line_str) <= mode.line_length
 
     first, *_, last = line_str.split("\n")
-    if len(first) > mode.line_length or len(last) > mode.line_length:
+    if width(first) > mode.line_length or width(last) > mode.line_length:
         return False
 
     # Traverse the AST to examine the context of the multiline string (MLS),
@@ -781,7 +792,7 @@ def is_line_short_enough(  # noqa: C901
     # store the leaves that contain parts of the MLS
     multiline_string_contexts: List[LN] = []
 
-    max_level_to_update = math.inf  # track the depth of the MLS
+    max_level_to_update: Union[int, float] = math.inf  # track the depth of the MLS
     for i, leaf in enumerate(line.leaves):
         if max_level_to_update == math.inf:
             had_comma: Optional[int] = None