add preview option support for blackd (#3217)

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

diff --git a/src/black/trans.py b/src/black/trans.py
index 74d052fe2dcbd0854d11bee16417777e28ed26eb..dc9c5520d5bdfcaf7e56bd8c93fae537e779f0ed 100644 (file)
--- a/src/black/trans.py
+++ b/src/black/trans.py
@@ -1,10 +1,11 @@
 """
 String transformers that can split and merge strings.
 """
 """
 String transformers that can split and merge strings.
 """

+import re
+import sys

 from abc import ABC, abstractmethod
 from collections import defaultdict
 from dataclasses import dataclass
 from abc import ABC, abstractmethod
 from collections import defaultdict
 from dataclasses import dataclass

-import re

 from typing import (
     Any,
     Callable,
 from typing import (
     Any,
     Callable,


@@ -21,29 +22,38 @@ from typing import (
     TypeVar,
     Union,
 )
     TypeVar,
     Union,
 )

-import sys

 
 if sys.version_info < (3, 8):
 
 if sys.version_info < (3, 8):

-    from typing_extensions import Literal, Final
+    from typing_extensions import Final, Literal

 else:
     from typing import Literal, Final
 
 from mypy_extensions import trait
 
 else:
     from typing import Literal, Final
 
 from mypy_extensions import trait
 

-from black.rusty import Result, Ok, Err
-
-from black.mode import Feature
-from black.nodes import syms, replace_child, parent_type
-from black.nodes import is_empty_par, is_empty_lpar, is_empty_rpar
-from black.nodes import OPENING_BRACKETS, CLOSING_BRACKETS, STANDALONE_COMMENT
-from black.lines import Line, append_leaves

 from black.brackets import BracketMatchError
 from black.comments import contains_pragma_comment
 from black.brackets import BracketMatchError
 from black.comments import contains_pragma_comment

-from black.strings import has_triple_quotes, get_string_prefix, assert_is_leaf_string
-from black.strings import normalize_string_quotes
-
-from blib2to3.pytree import Leaf, Node
+from black.lines import Line, append_leaves
+from black.mode import Feature
+from black.nodes import (
+    CLOSING_BRACKETS,
+    OPENING_BRACKETS,
+    STANDALONE_COMMENT,
+    is_empty_lpar,
+    is_empty_par,
+    is_empty_rpar,
+    parent_type,
+    replace_child,
+    syms,
+)
+from black.rusty import Err, Ok, Result
+from black.strings import (
+    assert_is_leaf_string,
+    get_string_prefix,
+    has_triple_quotes,
+    normalize_string_quotes,
+)

 from blib2to3.pgen2 import token
 from blib2to3.pgen2 import token

+from blib2to3.pytree import Leaf, Node

 
 
 class CannotTransform(Exception):
 
 
 class CannotTransform(Exception):


@@ -121,7 +131,7 @@ def hug_power_op(line: Line, features: Collection[Feature]) -> Iterator[Line]:
 
         return False
 
 
         return False
 

-    leaves: List[Leaf] = []
+    new_line = line.clone()

     should_hug = False
     for idx, leaf in enumerate(line.leaves):
         new_leaf = leaf.clone()
     should_hug = False
     for idx, leaf in enumerate(line.leaves):
         new_leaf = leaf.clone()


@@ -139,18 +149,14 @@ def hug_power_op(line: Line, features: Collection[Feature]) -> Iterator[Line]:
         if should_hug:
             new_leaf.prefix = ""
 
         if should_hug:
             new_leaf.prefix = ""
 

-        leaves.append(new_leaf)
-
-    yield Line(
-        mode=line.mode,
-        depth=line.depth,
-        leaves=leaves,
-        comments=line.comments,
-        bracket_tracker=line.bracket_tracker,
-        inside_brackets=line.inside_brackets,
-        should_split_rhs=line.should_split_rhs,
-        magic_trailing_comma=line.magic_trailing_comma,
-    )
+        # We have to be careful to make a new line properly:
+        # - bracket related metadata must be maintained (handled by Line.append)
+        # - comments need to copied over, updating the leaf IDs they're attached to
+        new_line.append(new_leaf, preformatted=True)
+        for comment_leaf in line.comments_after(leaf):
+            new_line.append(comment_leaf, preformatted=True)
+
+    yield new_line

 
 
 class StringTransformer(ABC):
 
 
 class StringTransformer(ABC):


@@ -365,7 +371,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin):
 
         is_valid_index = is_valid_index_factory(LL)
 
 
         is_valid_index = is_valid_index_factory(LL)
 

-        for (i, leaf) in enumerate(LL):
+        for i, leaf in enumerate(LL):

             if (
                 leaf.type == token.STRING
                 and is_valid_index(i + 1)
             if (
                 leaf.type == token.STRING
                 and is_valid_index(i + 1)


@@ -570,7 +576,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin):
 
         # Build the final line ('new_line') that this method will later return.
         new_line = line.clone()
 
         # Build the final line ('new_line') that this method will later return.
         new_line = line.clone()

-        for (i, leaf) in enumerate(LL):
+        for i, leaf in enumerate(LL):

             if i == string_idx:
                 new_line.append(string_leaf)
 
             if i == string_idx:
                 new_line.append(string_leaf)
 


@@ -691,7 +697,7 @@ class StringParenStripper(StringTransformer):
 
         is_valid_index = is_valid_index_factory(LL)
 
 
         is_valid_index = is_valid_index_factory(LL)
 

-        for (idx, leaf) in enumerate(LL):
+        for idx, leaf in enumerate(LL):

             # Should be a string...
             if leaf.type != token.STRING:
                 continue
             # Should be a string...
             if leaf.type != token.STRING:
                 continue


@@ -1713,7 +1719,7 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin):
         if parent_type(LL[0]) == syms.assert_stmt and LL[0].value == "assert":
             is_valid_index = is_valid_index_factory(LL)
 
         if parent_type(LL[0]) == syms.assert_stmt and LL[0].value == "assert":
             is_valid_index = is_valid_index_factory(LL)
 

-            for (i, leaf) in enumerate(LL):
+            for i, leaf in enumerate(LL):

                 # We MUST find a comma...
                 if leaf.type == token.COMMA:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1
                 # We MUST find a comma...
                 if leaf.type == token.COMMA:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1


@@ -1751,7 +1757,7 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin):
         ):
             is_valid_index = is_valid_index_factory(LL)
 
         ):
             is_valid_index = is_valid_index_factory(LL)
 

-            for (i, leaf) in enumerate(LL):
+            for i, leaf in enumerate(LL):

                 # We MUST find either an '=' or '+=' symbol...
                 if leaf.type in [token.EQUAL, token.PLUSEQUAL]:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1
                 # We MUST find either an '=' or '+=' symbol...
                 if leaf.type in [token.EQUAL, token.PLUSEQUAL]:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1


@@ -1794,7 +1800,7 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin):
         if syms.dictsetmaker in [parent_type(LL[0]), parent_type(LL[0].parent)]:
             is_valid_index = is_valid_index_factory(LL)
 
         if syms.dictsetmaker in [parent_type(LL[0]), parent_type(LL[0].parent)]:
             is_valid_index = is_valid_index_factory(LL)
 

-            for (i, leaf) in enumerate(LL):
+            for i, leaf in enumerate(LL):

                 # We MUST find a colon...
                 if leaf.type == token.COLON:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1
                 # We MUST find a colon...
                 if leaf.type == token.COLON:
                     idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1