Update beta link in docs

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index 19a023cff52db2e92d5cc0950125e20c96d24dff..e72db2b1e0650b95a68c3659fd351e461b677578 100644 (file)
--- a/black.py
+++ b/black.py
@@ -1,7 +1,7 @@
 import asyncio
 import asyncio

-import pickle

 from asyncio.base_events import BaseEventLoop
 from concurrent.futures import Executor, ProcessPoolExecutor
 from asyncio.base_events import BaseEventLoop
 from concurrent.futures import Executor, ProcessPoolExecutor

+from datetime import datetime

 from enum import Enum, Flag
 from functools import partial, wraps
 import io
 from enum import Enum, Flag
 from functools import partial, wraps
 import io


@@ -10,10 +10,11 @@ import logging
 from multiprocessing import Manager
 import os
 from pathlib import Path
 from multiprocessing import Manager
 import os
 from pathlib import Path

+import pickle

 import re
 import re

-import tokenize

 import signal
 import sys
 import signal
 import sys

+import tokenize

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


@@ -45,7 +46,7 @@ from blib2to3.pgen2 import driver, token
 from blib2to3.pgen2.parse import ParseError
 
 
 from blib2to3.pgen2.parse import ParseError
 
 

-__version__ = "18.5b1"
+__version__ = "18.6b1"

 DEFAULT_LINE_LENGTH = 88
 DEFAULT_EXCLUDES = (
     r"/(\.git|\.hg|\.mypy_cache|\.tox|\.venv|_build|buck-out|build|dist)/"
 DEFAULT_LINE_LENGTH = 88
 DEFAULT_EXCLUDES = (
     r"/(\.git|\.hg|\.mypy_cache|\.tox|\.venv|_build|buck-out|build|dist)/"


@@ -57,6 +58,7 @@ CACHE_DIR = Path(user_cache_dir("black", version=__version__))
 # types
 FileContent = str
 Encoding = str
 # types
 FileContent = str
 Encoding = str

+NewLine = str

 Depth = int
 NodeType = int
 LeafID = int
 Depth = int
 NodeType = int
 LeafID = int


@@ -335,8 +337,9 @@ def main(
         finally:
             shutdown(loop)
     if verbose or not quiet:
         finally:
             shutdown(loop)
     if verbose or not quiet:

-        out("All done! ✨ 🍰 ✨")
-        click.echo(str(report))
+        bang = "💥 💔 💥" if report.return_code else "✨ 🍰 ✨"
+        out(f"All done! {bang}")
+        click.secho(str(report), err=True)

     ctx.exit(report.return_code)
 
 
     ctx.exit(report.return_code)
 
 


@@ -468,8 +471,9 @@ def format_file_in_place(
     if src.suffix == ".pyi":
         mode |= FileMode.PYI
 
     if src.suffix == ".pyi":
         mode |= FileMode.PYI
 

+    then = datetime.utcfromtimestamp(src.stat().st_mtime)

     with open(src, "rb") as buf:
     with open(src, "rb") as buf:

-        newline, encoding, src_contents = prepare_input(buf.read())
+        src_contents, encoding, newline = decode_bytes(buf.read())

     try:
         dst_contents = format_file_contents(
             src_contents, line_length=line_length, fast=fast, mode=mode
     try:
         dst_contents = format_file_contents(
             src_contents, line_length=line_length, fast=fast, mode=mode


@@ -481,8 +485,9 @@ def format_file_in_place(
         with open(src, "w", encoding=encoding, newline=newline) as f:
             f.write(dst_contents)
     elif write_back == write_back.DIFF:
         with open(src, "w", encoding=encoding, newline=newline) as f:
             f.write(dst_contents)
     elif write_back == write_back.DIFF:

-        src_name = f"{src}  (original)"
-        dst_name = f"{src}  (formatted)"
+        now = datetime.utcnow()
+        src_name = f"{src}\t{then} +0000"
+        dst_name = f"{src}\t{now} +0000"

         diff_contents = diff(src_contents, dst_contents, src_name, dst_name)
         if lock:
             lock.acquire()
         diff_contents = diff(src_contents, dst_contents, src_name, dst_name)
         if lock:
             lock.acquire()


@@ -513,7 +518,8 @@ def format_stdin_to_stdout(
     `line_length`, `fast`, `is_pyi`, and `force_py36` arguments are passed to
     :func:`format_file_contents`.
     """
     `line_length`, `fast`, `is_pyi`, and `force_py36` arguments are passed to
     :func:`format_file_contents`.
     """

-    newline, encoding, src = prepare_input(sys.stdin.buffer.read())
+    then = datetime.utcnow()
+    src, encoding, newline = decode_bytes(sys.stdin.buffer.read())

     dst = src
     try:
         dst = format_file_contents(src, line_length=line_length, fast=fast, mode=mode)
     dst = src
     try:
         dst = format_file_contents(src, line_length=line_length, fast=fast, mode=mode)


@@ -523,26 +529,17 @@ def format_stdin_to_stdout(
         return False
 
     finally:
         return False
 
     finally:

+        f = io.TextIOWrapper(
+            sys.stdout.buffer, encoding=encoding, newline=newline, write_through=True
+        )

         if write_back == WriteBack.YES:
         if write_back == WriteBack.YES:

-            f = io.TextIOWrapper(
-                sys.stdout.buffer,
-                encoding=encoding,
-                newline=newline,
-                write_through=True,
-            )

             f.write(dst)
             f.write(dst)

-            f.detach()

         elif write_back == WriteBack.DIFF:
         elif write_back == WriteBack.DIFF:

-            src_name = "<stdin>  (original)"
-            dst_name = "<stdin>  (formatted)"
-            f = io.TextIOWrapper(
-                sys.stdout.buffer,
-                encoding=encoding,
-                newline=newline,
-                write_through=True,
-            )
+            now = datetime.utcnow()
+            src_name = f"STDIN\t{then} +0000"
+            dst_name = f"STDOUT\t{now} +0000"

             f.write(diff(src, dst, src_name, dst_name))
             f.write(diff(src, dst, src_name, dst_name))

-            f.detach()
+        f.detach()

 
 
 def format_file_contents(
 
 
 def format_file_contents(


@@ -603,17 +600,21 @@ def format_str(
     return dst_contents
 
 
     return dst_contents
 
 

-def prepare_input(src: bytes) -> Tuple[str, str, str]:
-    """Analyze `src` and return a tuple of (newline, encoding, decoded_contents)
+def decode_bytes(src: bytes) -> Tuple[FileContent, Encoding, NewLine]:
+    """Return a tuple of (decoded_contents, encoding, newline).

 
 

-    Where `newline` is either CRLF or LF, and `decoded_contents` is decoded with
-    universal newlines (i.e. only LF).
+    `newline` is either CRLF or LF but `decoded_contents` is decoded with
+    universal newlines (i.e. only contains LF).

     """
     srcbuf = io.BytesIO(src)
     encoding, lines = tokenize.detect_encoding(srcbuf.readline)
     """
     srcbuf = io.BytesIO(src)
     encoding, lines = tokenize.detect_encoding(srcbuf.readline)

+    if not lines:
+        return "", encoding, "\n"
+

     newline = "\r\n" if b"\r\n" == lines[0][-2:] else "\n"
     srcbuf.seek(0)
     newline = "\r\n" if b"\r\n" == lines[0][-2:] else "\n"
     srcbuf.seek(0)

-    return newline, encoding, io.TextIOWrapper(srcbuf, encoding).read()
+    with io.TextIOWrapper(srcbuf, encoding) as tiow:
+        return tiow.read(), encoding, newline

 
 
 GRAMMARS = [
 
 
 GRAMMARS = [


@@ -626,7 +627,7 @@ GRAMMARS = [
 def lib2to3_parse(src_txt: str) -> Node:
     """Given a string with source, return the lib2to3 Node."""
     grammar = pygram.python_grammar_no_print_statement
 def lib2to3_parse(src_txt: str) -> Node:
     """Given a string with source, return the lib2to3 Node."""
     grammar = pygram.python_grammar_no_print_statement

-    if src_txt[-1] != "\n":
+    if src_txt[-1:] != "\n":

         src_txt += "\n"
     for grammar in GRAMMARS:
         drv = driver.Driver(grammar, pytree.convert)
         src_txt += "\n"
     for grammar in GRAMMARS:
         drv = driver.Driver(grammar, pytree.convert)


@@ -771,6 +772,7 @@ UNPACKING_PARENTS = {
     syms.dictsetmaker,
     syms.listmaker,
     syms.testlist_gexp,
     syms.dictsetmaker,
     syms.listmaker,
     syms.testlist_gexp,

+    syms.testlist_star_expr,

 }
 TEST_DESCENDANTS = {
     syms.test,
 }
 TEST_DESCENDANTS = {
     syms.test,


@@ -1093,6 +1095,13 @@ class Line:
 
         return False
 
 
         return False
 

+    def contains_multiline_strings(self) -> bool:
+        for leaf in self.leaves:
+            if is_multiline_string(leaf):
+                return True
+
+        return False
+

     def maybe_remove_trailing_comma(self, closing: Leaf) -> bool:
         """Remove trailing comma if there is one and it's safe."""
         if not (
     def maybe_remove_trailing_comma(self, closing: Leaf) -> bool:
         """Remove trailing comma if there is one and it's safe."""
         if not (


@@ -1826,7 +1835,7 @@ def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str:  # noqa C901
             elif prevp.type == token.EQUAL and prevp_parent.type == syms.argument:
                 return NO
 
             elif prevp.type == token.EQUAL and prevp_parent.type == syms.argument:
                 return NO
 

-        elif t == token.NAME or t == token.NUMBER:
+        elif t in {token.NAME, token.NUMBER, token.STRING}:

             return NO
 
     elif p.type == syms.import_from:
             return NO
 
     elif p.type == syms.import_from:


@@ -2212,32 +2221,50 @@ def right_hand_split(
             result.append(leaf, preformatted=True)
             for comment_after in line.comments_after(leaf):
                 result.append(comment_after, preformatted=True)
             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
     assert opening_bracket and closing_bracket

+    body.should_explode = should_explode(body, opening_bracket)
+    bracket_split_succeeded_or_raise(head, body, tail)

     if (
     if (

+        # the body shouldn't be exploded
+        not body.should_explode

         # the opening bracket is an optional paren
         # the opening bracket is an optional paren

-        opening_bracket.type == token.LPAR
+        and opening_bracket.type == token.LPAR

         and not opening_bracket.value
         # the closing bracket is an optional paren
         and closing_bracket.type == token.RPAR
         and not closing_bracket.value
         and not opening_bracket.value
         # the closing bracket is an optional paren
         and closing_bracket.type == token.RPAR
         and not closing_bracket.value

-        # there are no standalone comments in the body
-        and not line.contains_standalone_comments(0)
-        # and it's not an import (optional parens are the only thing we can split
-        # on in this case; attempting a split without them is a waste of time)
+        # it's not an import (optional parens are the only thing we can split on
+        # in this case; attempting a split without them is a waste of time)

         and not line.is_import
         and not line.is_import

+        # there are no standalone comments in the body
+        and not body.contains_standalone_comments(0)
+        # and we can actually remove the parens
+        and can_omit_invisible_parens(body, line_length)

     ):
         omit = {id(closing_bracket), *omit}
     ):
         omit = {id(closing_bracket), *omit}

-        if can_omit_invisible_parens(body, line_length):
-            try:
-                yield from right_hand_split(line, line_length, py36=py36, omit=omit)
-                return
-            except CannotSplit:
-                pass
+        try:
+            yield from right_hand_split(line, line_length, py36=py36, omit=omit)
+            return
+
+        except CannotSplit:
+            if not (
+                can_be_split(body)
+                or is_line_short_enough(body, line_length=line_length)
+            ):
+                raise CannotSplit(
+                    "Splitting failed, body is still too long and can't be split."
+                )
+
+            elif head.contains_multiline_strings() or tail.contains_multiline_strings():
+                raise CannotSplit(
+                    "The current optional pair of parentheses is bound to fail to "
+                    "satisfy the splitting algorithm because the head or the tail "
+                    "contains multiline strings which by definition never fit one "
+                    "line."
+                )

 
     ensure_visible(opening_bracket)
     ensure_visible(closing_bracket)
 
     ensure_visible(opening_bracket)
     ensure_visible(closing_bracket)

-    body.should_explode = should_explode(body, opening_bracket)

     for result in (head, body, tail):
         if result:
             yield result
     for result in (head, body, tail):
         if result:
             yield result


@@ -2535,7 +2562,7 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
 
 
 def maybe_make_parens_invisible_in_atom(node: LN) -> bool:
 
 
 def maybe_make_parens_invisible_in_atom(node: LN) -> bool:

-    """If it's safe, make the parens in the atom `node` invisible, recusively."""
+    """If it's safe, make the parens in the atom `node` invisible, recursively."""

     if (
         node.type != syms.atom
         or is_empty_tuple(node)
     if (
         node.type != syms.atom
         or is_empty_tuple(node)


@@ -3182,6 +3209,42 @@ def is_line_short_enough(line: Line, *, line_length: int, line_str: str = "") ->
     )
 
 
     )
 
 

+def can_be_split(line: Line) -> bool:
+    """Return False if the line cannot be split *for sure*.
+
+    This is not an exhaustive search but a cheap heuristic that we can use to
+    avoid some unfortunate formattings (mostly around wrapping unsplittable code
+    in unnecessary parentheses).
+    """
+    leaves = line.leaves
+    if len(leaves) < 2:
+        return False
+
+    if leaves[0].type == token.STRING and leaves[1].type == token.DOT:
+        call_count = 0
+        dot_count = 0
+        next = leaves[-1]
+        for leaf in leaves[-2::-1]:
+            if leaf.type in OPENING_BRACKETS:
+                if next.type not in CLOSING_BRACKETS:
+                    return False
+
+                call_count += 1
+            elif leaf.type == token.DOT:
+                dot_count += 1
+            elif leaf.type == token.NAME:
+                if not (next.type == token.DOT or next.type in OPENING_BRACKETS):
+                    return False
+
+            elif leaf.type not in CLOSING_BRACKETS:
+                return False
+
+            if dot_count > 1 and call_count > 1:
+                return False
+
+    return True
+
+

 def can_omit_invisible_parens(line: Line, line_length: int) -> bool:
     """Does `line` have a shape safe to reformat without optional parens around it?
 
 def can_omit_invisible_parens(line: Line, line_length: int) -> bool:
     """Does `line` have a shape safe to reformat without optional parens around it?