]> git.madduck.net Git - etc/vim.git/commitdiff

madduck's git repository

Every one of the projects in this repository is available at the canonical URL git://git.madduck.net/madduck/pub/<projectpath> — see each project's metadata for the exact URL.

All patches and comments are welcome. Please squash your changes to logical commits before using git-format-patch and git-send-email to patches@git.madduck.net. If you'd read over the Git project's submission guidelines and adhered to them, I'd be especially grateful.

SSH access, as well as push access can be individually arranged.

If you use my repositories frequently, consider adding the following snippet to ~/.gitconfig and using the third clone URL listed for each project:

[url "git://git.madduck.net/madduck/"]
  insteadOf = madduck:

Automatic parentheses management
authorŁukasz Langa <lukasz@langa.pl>
Thu, 5 Apr 2018 04:45:01 +0000 (21:45 -0700)
committerŁukasz Langa <lukasz@langa.pl>
Wed, 11 Apr 2018 08:36:18 +0000 (01:36 -0700)
Fixes #4

README.md
black.py
docs/reference/reference_functions.rst
tests/composition.py
tests/empty_lines.py
tests/expression.diff
tests/expression.py
tests/function.py
tests/import_spacing.py
tests/test_black.py

index 35f1379e40115a0d4eed56243cc17e89ce8aa29e..06b732466eb3b305307992f35a23df99cc476956 100644 (file)
--- a/README.md
+++ b/README.md
@@ -300,6 +300,22 @@ This behaviour may raise ``W503 line break before binary operator`` warnings in
 style guide enforcement tools like Flake8. Since ``W503`` is not PEP 8 compliant,
 you should tell Flake8 to ignore these warnings.
 
+### Parentheses
+
+Some parentheses are optional in the Python grammar.  Any expression can
+be wrapped in a pair of parentheses to form an atom.  There are a few
+interesting cases:
+
+- `if (...):`
+- `while (...):`
+- `for (...) in (...):`
+- `assert (...), (...)`
+- `from X import (...)`
+
+In those cases, parentheses are removed when the entire statement fits
+in one line, or if the inner expression doesn't have any delimiters to
+further split on.  Otherwise, the parentheses are always added.
+
 
 ## Editor integration
 
@@ -479,6 +495,8 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 * added `--quiet` (#78)
 
+* added automatic parentheses management (#4)
+
 * added [pre-commit](https://pre-commit.com) integration (#103, #104)
 
 * fixed reporting on `--check` with multiple files (#101, #102)
index 19871aa7e7e5576cebd917310bba117bc447f5b4..3e3ae0a1dcc33fc6eba28ad965533975b1b2a90c 100644 (file)
--- a/black.py
+++ b/black.py
@@ -17,6 +17,7 @@ import sys
 from typing import (
     Any,
     Callable,
+    Collection,
     Dict,
     Generic,
     Iterable,
@@ -315,12 +316,12 @@ def format_stdin_to_stdout(
     `line_length` and `fast` arguments are passed to :func:`format_file_contents`.
     """
     src = sys.stdin.read()
+    dst = src
     try:
         dst = format_file_contents(src, line_length=line_length, fast=fast)
         return True
 
     except NothingChanged:
-        dst = src
         return False
 
     finally:
@@ -582,6 +583,7 @@ class BracketTracker:
         """Return the highest priority of a delimiter found on the line.
 
         Values are consistent with what `is_delimiter()` returns.
+        Raises ValueError on no delimiters.
         """
         return max(v for k, v in self.delimiters.items() if k not in exclude)
 
@@ -608,7 +610,7 @@ class Line:
 
         Inline comments are put aside.
         """
-        has_value = leaf.value.strip()
+        has_value = leaf.type in BRACKETS or bool(leaf.value.strip())
         if not has_value:
             return
 
@@ -709,12 +711,12 @@ class Line:
             and self.leaves[0].value == "yield"
         )
 
-    @property
-    def contains_standalone_comments(self) -> bool:
+    def contains_standalone_comments(self, depth_limit: int = sys.maxsize) -> bool:
         """If so, needs to be split before emitting."""
         for leaf in self.leaves:
             if leaf.type == STANDALONE_COMMENT:
-                return True
+                if leaf.bracket_depth <= depth_limit:
+                    return True
 
         return False
 
@@ -1077,15 +1079,22 @@ class LineGenerator(Visitor[Line]):
         # DEDENT has no value. Additionally, in blib2to3 it never holds comments.
         yield from self.line(-1)
 
-    def visit_stmt(self, node: Node, keywords: Set[str]) -> Iterator[Line]:
+    def visit_stmt(
+        self, node: Node, keywords: Set[str], parens: Set[str]
+    ) -> Iterator[Line]:
         """Visit a statement.
 
         This implementation is shared for `if`, `while`, `for`, `try`, `except`,
-        `def`, `with`, and `class`.
+        `def`, `with`, `class`, and `assert`.
+
+        The relevant Python language `keywords` for a given statement will be
+        NAME leaves within it. This methods puts those on a separate line.
 
-        The relevant Python language `keywords` for a given statement will be NAME
-        leaves within it. This methods puts those on a separate line.
+        `parens` holds pairs of nodes where invisible parentheses should be put.
+        Keys hold nodes after which opening parentheses should be put, values
+        hold nodes before which closing parentheses should be put.
         """
+        normalize_invisible_parens(node, parens_after=parens)
         for child in node.children:
             if child.type == token.NAME and child.value in keywords:  # type: ignore
                 yield from self.line()
@@ -1125,6 +1134,32 @@ class LineGenerator(Visitor[Line]):
             yield from self.line()
             yield from self.visit(child)
 
+    def visit_import_from(self, node: Node) -> Iterator[Line]:
+        """Visit import_from and maybe put invisible parentheses.
+
+        This is separate from `visit_stmt` because import statements don't
+        support arbitrary atoms and thus handling of parentheses is custom.
+        """
+        check_lpar = False
+        for index, child in enumerate(node.children):
+            if check_lpar:
+                if child.type == token.LPAR:
+                    # make parentheses invisible
+                    child.value = ""  # type: ignore
+                    node.children[-1].value = ""  # type: ignore
+                else:
+                    # insert invisible parentheses
+                    node.insert_child(index, Leaf(token.LPAR, ""))
+                    node.append_child(Leaf(token.RPAR, ""))
+                break
+
+            check_lpar = (
+                child.type == token.NAME and child.value == "import"  # type: ignore
+            )
+
+        for child in node.children:
+            yield from self.visit(child)
+
     def visit_SEMI(self, leaf: Leaf) -> Iterator[Line]:
         """Remove a semicolon and put the other statement on a separate line."""
         yield from self.line()
@@ -1155,18 +1190,23 @@ class LineGenerator(Visitor[Line]):
     def __attrs_post_init__(self) -> None:
         """You are in a twisty little maze of passages."""
         v = self.visit_stmt
-        self.visit_if_stmt = partial(v, keywords={"if", "else", "elif"})
-        self.visit_while_stmt = partial(v, keywords={"while", "else"})
-        self.visit_for_stmt = partial(v, keywords={"for", "else"})
-        self.visit_try_stmt = partial(v, keywords={"try", "except", "else", "finally"})
-        self.visit_except_clause = partial(v, keywords={"except"})
-        self.visit_funcdef = partial(v, keywords={"def"})
-        self.visit_with_stmt = partial(v, keywords={"with"})
-        self.visit_classdef = partial(v, keywords={"class"})
+        Ø: Set[str] = set()
+        self.visit_assert_stmt = partial(v, keywords={"assert"}, parens={"assert", ","})
+        self.visit_if_stmt = partial(v, keywords={"if", "else", "elif"}, parens={"if"})
+        self.visit_while_stmt = partial(v, keywords={"while", "else"}, parens={"while"})
+        self.visit_for_stmt = partial(v, keywords={"for", "else"}, parens={"for", "in"})
+        self.visit_try_stmt = partial(
+            v, keywords={"try", "except", "else", "finally"}, parens=Ø
+        )
+        self.visit_except_clause = partial(v, keywords={"except"}, parens=Ø)
+        self.visit_with_stmt = partial(v, keywords={"with"}, parens=Ø)
+        self.visit_funcdef = partial(v, keywords={"def"}, parens=Ø)
+        self.visit_classdef = partial(v, keywords={"class"}, parens=Ø)
         self.visit_async_funcdef = self.visit_async_stmt
         self.visit_decorated = self.visit_decorators
 
 
+IMPLICIT_TUPLE = {syms.testlist, syms.testlist_star_expr, syms.exprlist}
 BRACKET = {token.LPAR: token.RPAR, token.LSQB: token.RSQB, token.LBRACE: token.RBRACE}
 OPENING_BRACKETS = set(BRACKET.keys())
 CLOSING_BRACKETS = set(BRACKET.values())
@@ -1215,14 +1255,17 @@ def whitespace(leaf: Leaf) -> str:  # noqa C901
                     return prevp.prefix
 
         elif prevp.type == token.DOUBLESTAR:
-            if prevp.parent and prevp.parent.type in {
-                syms.arglist,
-                syms.argument,
-                syms.dictsetmaker,
-                syms.parameters,
-                syms.typedargslist,
-                syms.varargslist,
-            }:
+            if (
+                prevp.parent
+                and prevp.parent.type in {
+                    syms.arglist,
+                    syms.argument,
+                    syms.dictsetmaker,
+                    syms.parameters,
+                    syms.typedargslist,
+                    syms.varargslist,
+                }
+            ):
                 return NO
 
         elif prevp.type == token.COLON:
@@ -1382,9 +1425,10 @@ def whitespace(leaf: Leaf) -> str:  # noqa C901
 
             prevp_parent = prevp.parent
             assert prevp_parent is not None
-            if prevp.type == token.COLON and prevp_parent.type in {
-                syms.subscript, syms.sliceop
-            }:
+            if (
+                prevp.type == token.COLON
+                and prevp_parent.type in {syms.subscript, syms.sliceop}
+            ):
                 return NO
 
             elif prevp.type == token.EQUAL and prevp_parent.type == syms.argument:
@@ -1607,7 +1651,7 @@ def split_line(
     if (
         len(line_str) <= line_length
         and "\n" not in line_str  # multiline strings
-        and not line.contains_standalone_comments
+        and not line.contains_standalone_comments()
     ):
         yield line
         return
@@ -1673,9 +1717,7 @@ def left_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
     if body_leaves:
         normalize_prefix(body_leaves[0], inside_brackets=True)
     # Build the new lines.
-    for result, leaves in (
-        (head, head_leaves), (body, body_leaves), (tail, tail_leaves)
-    ):
+    for result, leaves in (head, head_leaves), (body, body_leaves), (tail, tail_leaves):
         for leaf in leaves:
             result.append(leaf, preformatted=True)
             for comment_after in line.comments_after(leaf):
@@ -1686,7 +1728,9 @@ def left_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
             yield result
 
 
-def right_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
+def right_hand_split(
+    line: Line, py36: bool = False, omit: Collection[LeafID] = ()
+) -> Iterator[Line]:
     """Split line into many lines, starting with the last matching bracket pair."""
     head = Line(depth=line.depth)
     body = Line(depth=line.depth + 1, inside_brackets=True)
@@ -1696,14 +1740,16 @@ def right_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
     head_leaves: List[Leaf] = []
     current_leaves = tail_leaves
     opening_bracket = None
+    closing_bracket = None
     for leaf in reversed(line.leaves):
         if current_leaves is body_leaves:
             if leaf is opening_bracket:
                 current_leaves = head_leaves if body_leaves else tail_leaves
         current_leaves.append(leaf)
         if current_leaves is tail_leaves:
-            if leaf.type in CLOSING_BRACKETS:
+            if leaf.type in CLOSING_BRACKETS and id(leaf) not in omit:
                 opening_bracket = leaf.opening_bracket
+                closing_bracket = leaf
                 current_leaves = body_leaves
     tail_leaves.reverse()
     body_leaves.reverse()
@@ -1711,15 +1757,36 @@ def right_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
     # Since body is a new indent level, remove spurious leading whitespace.
     if body_leaves:
         normalize_prefix(body_leaves[0], inside_brackets=True)
+    elif not head_leaves:
+        # No `head` and no `body` means the split failed. `tail` has all content.
+        raise CannotSplit("No brackets found")
+
     # Build the new lines.
-    for result, leaves in (
-        (head, head_leaves), (body, body_leaves), (tail, tail_leaves)
-    ):
+    for result, leaves in (head, head_leaves), (body, body_leaves), (tail, tail_leaves):
         for leaf in leaves:
             result.append(leaf, preformatted=True)
             for comment_after in line.comments_after(leaf):
                 result.append(comment_after, preformatted=True)
     bracket_split_succeeded_or_raise(head, body, tail)
+    assert opening_bracket and closing_bracket
+    if (
+        opening_bracket.type == token.LPAR
+        and not opening_bracket.value
+        and closing_bracket.type == token.RPAR
+        and not closing_bracket.value
+    ):
+        # These parens were optional. If there aren't any delimiters or standalone
+        # comments in the body, they were unnecessary and another split without
+        # them should be attempted.
+        if not (
+            body.bracket_tracker.delimiters or line.contains_standalone_comments(0)
+        ):
+            omit = {id(closing_bracket), *omit}
+            yield from right_hand_split(line, py36=py36, omit=omit)
+            return
+
+    ensure_visible(opening_bracket)
+    ensure_visible(closing_bracket)
     for result in (head, body, tail):
         if result:
             yield result
@@ -1833,12 +1900,7 @@ def delimiter_split(line: Line, py36: bool = False) -> Iterator[Line]:
 @dont_increase_indentation
 def standalone_comment_split(line: Line, py36: bool = False) -> Iterator[Line]:
     """Split standalone comments from the rest of the line."""
-    for leaf in line.leaves:
-        if leaf.type == STANDALONE_COMMENT:
-            if leaf.bracket_depth == 0:
-                break
-
-    else:
+    if not line.contains_standalone_comments(0):
         raise CannotSplit("Line does not have any standalone comments")
 
     current_line = Line(depth=line.depth, inside_brackets=line.inside_brackets)
@@ -1950,6 +2012,109 @@ def normalize_string_quotes(leaf: Leaf) -> None:
     leaf.value = f"{prefix}{new_quote}{new_body}{new_quote}"
 
 
+def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
+    """Make existing optional parentheses invisible or create new ones.
+
+    Standardizes on visible parentheses for single-element tuples, and keeps
+    existing visible parentheses for other tuples and generator expressions.
+    """
+    check_lpar = False
+    for child in list(node.children):
+        if check_lpar:
+            if child.type == syms.atom:
+                if not (
+                    is_empty_tuple(child)
+                    or is_one_tuple(child)
+                    or max_delimiter_priority_in_atom(child) >= COMMA_PRIORITY
+                ):
+                    first = child.children[0]
+                    last = child.children[-1]
+                    if first.type == token.LPAR and last.type == token.RPAR:
+                        # make parentheses invisible
+                        first.value = ""  # type: ignore
+                        last.value = ""  # type: ignore
+            elif is_one_tuple(child):
+                # wrap child in visible parentheses
+                lpar = Leaf(token.LPAR, "(")
+                rpar = Leaf(token.RPAR, ")")
+                index = child.remove() or 0
+                node.insert_child(index, Node(syms.atom, [lpar, child, rpar]))
+            else:
+                # wrap child in invisible parentheses
+                lpar = Leaf(token.LPAR, "")
+                rpar = Leaf(token.RPAR, "")
+                index = child.remove() or 0
+                node.insert_child(index, Node(syms.atom, [lpar, child, rpar]))
+
+        check_lpar = isinstance(child, Leaf) and child.value in parens_after
+
+
+def is_empty_tuple(node: LN) -> bool:
+    """Return True if `node` holds an empty tuple."""
+    return (
+        node.type == syms.atom
+        and len(node.children) == 2
+        and node.children[0].type == token.LPAR
+        and node.children[1].type == token.RPAR
+    )
+
+
+def is_one_tuple(node: LN) -> bool:
+    """Return True if `node` holds a tuple with one element, with or without parens."""
+    if node.type == syms.atom:
+        if len(node.children) != 3:
+            return False
+
+        lpar, gexp, rpar = node.children
+        if not (
+            lpar.type == token.LPAR
+            and gexp.type == syms.testlist_gexp
+            and rpar.type == token.RPAR
+        ):
+            return False
+
+        return len(gexp.children) == 2 and gexp.children[1].type == token.COMMA
+
+    return (
+        node.type in IMPLICIT_TUPLE
+        and len(node.children) == 2
+        and node.children[1].type == token.COMMA
+    )
+
+
+def max_delimiter_priority_in_atom(node: LN) -> int:
+    if node.type != syms.atom:
+        return 0
+
+    first = node.children[0]
+    last = node.children[-1]
+    if first.type == token.LPAR and last.type == token.RPAR:
+        bt = BracketTracker()
+        for c in node.children[1:-1]:
+            if isinstance(c, Leaf):
+                bt.mark(c)
+            else:
+                for leaf in c.leaves():
+                    bt.mark(leaf)
+    try:
+        return bt.max_delimiter_priority()
+
+    except ValueError:
+        return 0
+
+
+def ensure_visible(leaf: Leaf) -> None:
+    """Make sure parentheses are visible.
+
+    They could be invisible as part of some statements (see
+    :func:`normalize_invible_parens` and :func:`visit_import_from`).
+    """
+    if leaf.type == token.LPAR:
+        leaf.value = "("
+    elif leaf.type == token.RPAR:
+        leaf.value = ")"
+
+
 def is_python36(node: Node) -> bool:
     """Return True if the current file is using Python 3.6+ features.
 
index 4e7fb837222d1d0f477f85c2a2823a9ba0d6d461..2b8c08e0042a94505b9822a2b9314fef7bcc10a5 100644 (file)
@@ -18,8 +18,12 @@ Assertions and checks
 
 .. autofunction:: black.is_delimiter
 
+.. autofunction:: black.is_empty_tuple
+
 .. autofunction:: black.is_import
 
+.. autofunction:: black.is_one_tuple
+
 .. autofunction:: black.is_python36
 
 Formatting
@@ -58,6 +62,8 @@ Split functions
 
 .. autofunction:: black.right_hand_split
 
+.. autofunction:: black.standalone_comment_split
+
 .. autofunction:: black.split_line
 
 .. autofunction:: black.bracket_split_succeeded_or_raise
@@ -71,6 +77,8 @@ Utilities
 
 .. autofunction:: black.diff
 
+.. autofunction:: black.ensure_visible
+
 .. autofunction:: black.generate_comments
 
 .. autofunction:: black.make_comment
@@ -79,6 +87,8 @@ Utilities
 
 .. autofunction:: black.normalize_string_quotes
 
+.. autofunction:: black.normalize_invisible_parens
+
 .. autofunction:: black.preceding_leaf
 
 .. autofunction:: black.whitespace
index fb27b3e55304914e2cb7f3019ed43de7de211280..287888d984e086251610070df4e2316cac7dadf7 100644 (file)
@@ -19,3 +19,16 @@ class C:
                 "2 files reformatted, 2 files left unchanged, "
                 "2 files failed to reformat.",
             )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    # Rule 2
+                    and i % 3 == 0
+                ):
+                    while (
+                        # Just a comment
+                        call()
+                        # Another
+                    ):
+                        print(i)
index d001db42f04768e6226b1fa3348afe427a924acd..0edeb014a8f91e4bed3d9864e29798264f22847d 100644 (file)
@@ -113,23 +113,29 @@ def f():
             return NO
 
         if prevp.type == token.EQUAL:
-            if prevp.parent and prevp.parent.type in {
-                syms.typedargslist,
-                syms.varargslist,
-                syms.parameters,
-                syms.arglist,
-                syms.argument,
-            }:
+            if (
+                prevp.parent
+                and prevp.parent.type in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.argument,
+                }
+            ):
                 return NO
 
         elif prevp.type == token.DOUBLESTAR:
-            if prevp.parent and prevp.parent.type in {
-                syms.typedargslist,
-                syms.varargslist,
-                syms.parameters,
-                syms.arglist,
-                syms.dictsetmaker,
-            }:
+            if (
+                prevp.parent
+                and prevp.parent.type in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.dictsetmaker,
+                }
+            ):
                 return NO
 
 
@@ -167,11 +173,14 @@ def g():
             return NO
 
         if prevp.type == token.EQUAL:
-            if prevp.parent and prevp.parent.type in {
-                syms.typedargslist,
-                syms.varargslist,
-                syms.parameters,
-                syms.arglist,
-                syms.argument,
-            }:
+            if (
+                prevp.parent
+                and prevp.parent.type in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.argument,
+                }
+            ):
                 return NO
index f37b16bde745c601f6c692bcdb951c4161a12267..965aa00e7fac3de4402b456c85151d95de3b397d 100644 (file)
  ]
  slice[0]
  slice[0:1]
-@@ -114,73 +123,92 @@
+@@ -114,78 +123,104 @@
  numpy[-(c + 1):, d]
  numpy[:, l[-2]]
  numpy[:, ::-1]
  
  async def f():
      await some.complicated[0].call(with_args=(True or (1 is not 1)))
+-for x, in (1,), (2,), (3,): ...
+-for y in (): ...
+-for z in (i for i in (1, 2, 3)): ...
+-for i in (call()): ...
+-for j in (1 + (2 + 3)): ...
+-while(this and that): ...
 -if (
 -    threading.current_thread() != threading.main_thread() and
 -    threading.current_thread() != threading.main_thread() or
 -):
 -    return True
 +
++
++for (x,) in (1,), (2,), (3,):
++    ...
++for y in ():
++    ...
++for z in (i for i in (1, 2, 3)):
++    ...
++for i in call():
++    ...
++for j in 1 + (2 + 3):
++    ...
++while this and that:
++    ...
 +if (
 +    threading.current_thread() != threading.main_thread()
 +    and threading.current_thread() != threading.main_thread()
index 3cd0c61984b684b8bdf1ad33efd5516c62f36cf5..b03abfa0e1b77e229c7cc308c24d803627e49911 100644 (file)
@@ -144,7 +144,12 @@ def gen():
 
 async def f():
     await some.complicated[0].call(with_args=(True or (1 is not 1)))
-
+for x, in (1,), (2,), (3,): ...
+for y in (): ...
+for z in (i for i in (1, 2, 3)): ...
+for i in (call()): ...
+for j in (1 + (2 + 3)): ...
+while(this and that): ...
 if (
     threading.current_thread() != threading.main_thread() and
     threading.current_thread() != threading.main_thread() or
@@ -356,6 +361,18 @@ async def f():
     await some.complicated[0].call(with_args=(True or (1 is not 1)))
 
 
+for (x,) in (1,), (2,), (3,):
+    ...
+for y in ():
+    ...
+for z in (i for i in (1, 2, 3)):
+    ...
+for i in call():
+    ...
+for j in 1 + (2 + 3):
+    ...
+while this and that:
+    ...
 if (
     threading.current_thread() != threading.main_thread()
     and threading.current_thread() != threading.main_thread()
index 584474c1bb9b53c44cd7f0d2ad72694d8f7f8e45..6cf6dbc9a1b4d16da5874ee3fbd0e5b870c2771c 100644 (file)
@@ -33,7 +33,7 @@ def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r''
  assert task._cancel_stack[:len(old_stack)] == old_stack
 def spaces_types(a: int = 1, b: tuple = (), c: list = [], d: dict = {}, e: bool = True, f: int = -1, g: int = 1 if False else 2, h: str = "", i: str = r''): ...
 def spaces2(result= _core.Value(None)):
- ...
+ assert fut is self._read_fut, (fut, self._read_fut)
     # EMPTY LINE WITH WHITESPACE (this comment will be removed)
 def example(session):
     result = session.query(models.Customer.id).filter(
@@ -146,7 +146,7 @@ def spaces_types(
 
 
 def spaces2(result=_core.Value(None)):
-    ...
+    assert fut is self._read_fut, (fut, self._read_fut)
 
 
 def example(session):
index e9f7330db32bc6d93f11cddf0757a4e425982634..4091148d16231106377f1e43d82be344b809f21c 100644 (file)
@@ -18,7 +18,10 @@ from ..queues import *
 from ..streams import *
 
 from .a.b.c.subprocess import *
-from . import tasks
+from . import (tasks)
+from . import (A, B, C)
+from . import SomeVeryLongNameAndAllOfItsAdditionalLetters1, \
+              SomeVeryLongNameAndAllOfItsAdditionalLetters2
 
 __all__ = (
     base_events.__all__
@@ -58,6 +61,11 @@ from ..streams import *
 
 from .a.b.c.subprocess import *
 from . import tasks
+from . import A, B, C
+from . import (
+    SomeVeryLongNameAndAllOfItsAdditionalLetters1,
+    SomeVeryLongNameAndAllOfItsAdditionalLetters2,
+)
 
 __all__ = (
     base_events.__all__
index d2359cb51a3ad51c219724bca6334d4153ea7d30..f71f9b3f910eebdb09c7629b6853385c27691ce2 100644 (file)
@@ -174,7 +174,14 @@ class BlackTestCase(unittest.TestCase):
             sys.stdout = hold_stdout
             os.unlink(tmp_file)
         actual = actual.rstrip() + "\n"  # the diff output has a trailing space
-        self.assertEqual(expected, actual)
+        if expected != actual:
+            dump = black.dump_to_file(actual)
+            msg = (
+                f"Expected diff isn't equal to the actual. If you made changes "
+                f"to expression.py and this is an anticipated difference, "
+                f"overwrite tests/expression.diff with {dump}."
+            )
+            self.assertEqual(expected, actual, msg)
 
     @patch("black.dump_to_file", dump_to_stderr)
     def test_fstring(self) -> None: