Check for broken symlinks before checking file data (#202)

[etc/vim.git] / README.md

diff --git a/README.md b/README.md
index 9801ec9ca31555c7c40ad5c68933903f2a29aa13..3f62eec20b65423924f548faee03d97da5329651 100644 (file)
--- a/README.md
+++ b/README.md
@@ -3,10 +3,10 @@
 
 <p align="center">
 <a href="https://travis-ci.org/ambv/black"><img alt="Build Status" src="https://travis-ci.org/ambv/black.svg?branch=master"></a>
 
 <p align="center">
 <a href="https://travis-ci.org/ambv/black"><img alt="Build Status" src="https://travis-ci.org/ambv/black.svg?branch=master"></a>

-<a href="http://black.readthedocs.io/en/latest/?badge=latest"><img alt="Documentation Status" src="http://readthedocs.org/projects/black/badge/?version=latest"></a>
+<a href="http://black.readthedocs.io/en/stable/?badge=stable"><img alt="Documentation Status" src="http://readthedocs.org/projects/black/badge/?version=stable"></a>

 <a href="https://coveralls.io/github/ambv/black?branch=master"><img alt="Coverage Status" src="https://coveralls.io/repos/github/ambv/black/badge.svg?branch=master"></a>
 <a href="https://coveralls.io/github/ambv/black?branch=master"><img alt="Coverage Status" src="https://coveralls.io/repos/github/ambv/black/badge.svg?branch=master"></a>

-<a href="https://github.com/ambv/black/blob/master/LICENSE"><img alt="License: MIT" src="http://black.readthedocs.io/en/latest/_static/license.svg"></a>
-<a href="https://pypi.python.org/pypi/black"><img alt="PyPI" src="http://black.readthedocs.io/en/latest/_static/pypi.svg"></a>
+<a href="https://github.com/ambv/black/blob/master/LICENSE"><img alt="License: MIT" src="http://black.readthedocs.io/en/stable/_static/license.svg"></a>
+<a href="https://pypi.python.org/pypi/black"><img alt="PyPI" src="http://black.readthedocs.io/en/stable/_static/pypi.svg"></a>

 <a href="https://github.com/ambv/black"><img alt="Code style: black" src="https://img.shields.io/badge/code%20style-black-000000.svg"></a>
 </p>
 
 <a href="https://github.com/ambv/black"><img alt="Code style: black" src="https://img.shields.io/badge/code%20style-black-000000.svg"></a>
 </p>
 


@@ -14,7 +14,7 @@
 
 
 *Black* is the uncompromising Python code formatter.  By using it, you
 
 
 *Black* is the uncompromising Python code formatter.  By using it, you

-agree to cease control over minutiae of hand-formatting.  In return,
+agree to cede control over minutiae of hand-formatting.  In return,

 *Black* gives you speed, determinism, and freedom from `pycodestyle`
 nagging about formatting.  You will save time and mental energy for
 more important matters.
 *Black* gives you speed, determinism, and freedom from `pycodestyle`
 nagging about formatting.  You will save time and mental energy for
 more important matters.


@@ -74,7 +74,7 @@ Options:
 * it will read from standard input and write to standard output if `-`
   is used as the filename;
 * it only outputs messages to users on standard error;
 * it will read from standard input and write to standard output if `-`
   is used as the filename;
 * it only outputs messages to users on standard error;

-* exits with code 0 unless an internal error occured (or `--check` was
+* exits with code 0 unless an internal error occurred (or `--check` was

   used).
 
 
   used).
 
 


@@ -106,9 +106,9 @@ the same effect, as a courtesy for straddling code.
 
 *Black* ignores previous formatting and applies uniform horizontal
 and vertical whitespace to your code.  The rules for horizontal
 
 *Black* ignores previous formatting and applies uniform horizontal
 and vertical whitespace to your code.  The rules for horizontal

-whitespace are pretty obvious and can be summarized as: do whatever
-makes `pycodestyle` happy.  The coding style used by *Black* can be
-viewed as a strict subset of PEP 8.
+whitespace can be summarized as: do whatever makes `pycodestyle` happy.
+The coding style used by *Black* can be viewed as a strict subset of
+PEP 8.

 
 As for vertical whitespace, *Black* tries to render one full expression
 or simple statement per line.  If this fits the allotted line length,
 
 As for vertical whitespace, *Black* tries to render one full expression
 or simple statement per line.  If this fits the allotted line length,


@@ -176,6 +176,14 @@ between two distinct sections of the code that otherwise share the same
 indentation level (like the arguments list and the docstring in the
 example above).
 
 indentation level (like the arguments list and the docstring in the
 example above).
 

+If a line of "from" imports cannot fit in the allotted length, it's always split
+into one per line.  Imports tend to change often and this minimizes diffs, as well
+as enables readers of code to easily find which commit introduced a particular
+import.  This exception also makes *Black* compatible with
+[isort](https://pypi.org/p/isort/).  Use `multi_line_output=3`,
+`include_trailing_comma=True`, `force_grid_wrap=0`, and `line_length=88` in your
+isort config.
+

 
 ### Line length
 
 
 ### Line length
 


@@ -218,10 +226,7 @@ bother you if you overdo it by a few km/h".
 
 *Black* avoids spurious vertical whitespace.  This is in the spirit of
 PEP 8 which says that in-function vertical whitespace should only be
 
 *Black* avoids spurious vertical whitespace.  This is in the spirit of
 PEP 8 which says that in-function vertical whitespace should only be

-used sparingly.  One exception is control flow statements: *Black* will
-always emit an extra empty line after ``return``, ``raise``, ``break``,
-``continue``, and ``yield``.  This is to make changes in control flow
-more prominent to readers of your code.
+used sparingly.

 
 *Black* will allow single empty lines inside functions, and single and
 double empty lines on module level left by the original editors, except
 
 *Black* will allow single empty lines inside functions, and single and
 double empty lines on module level left by the original editors, except


@@ -230,11 +235,9 @@ are always reformatted to fit minimal space, this whitespace is lost.
 
 It will also insert proper spacing before and after function definitions.
 It's one line before and after inner functions and two lines before and
 
 It will also insert proper spacing before and after function definitions.
 It's one line before and after inner functions and two lines before and

-after module-level functions.  *Black* will put those empty lines also
-between the function definition and any standalone comments that
-immediately precede the given function.  If you want to comment on the
-entire function, use a docstring or put a leading comment in the function
-body.
+after module-level functions.  *Black* will not put empty lines between
+function/class definitions and standalone comments that immediately precede
+the given function/class.

 
 
 ### Trailing commas
 
 
 ### Trailing commas


@@ -271,6 +274,11 @@ keep it.
 and `'''`).  It will replace the latter with the former as long as it
 does not result in more backslash escapes than before.
 
 and `'''`).  It will replace the latter with the former as long as it
 does not result in more backslash escapes than before.
 

+*Black* also standardizes string prefixes, making them always lowercase.
+On top of that, if your code is already Python 3.6+ only or it's using
+the `unicode_literals` future import, *Black* will remove `u` from the
+string prefix as it is meaningless in those scenarios.
+

 The main reason to standardize on a single form of quotes is aesthetics.
 Having one kind of quotes everywhere reduces reader distraction.
 It will also enable a future version of *Black* to merge consecutive
 The main reason to standardize on a single form of quotes is aesthetics.
 Having one kind of quotes everywhere reduces reader distraction.
 It will also enable a future version of *Black* to merge consecutive


@@ -300,6 +308,19 @@ 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.
 
 style guide enforcement tools like Flake8. Since ``W503`` is not PEP 8 compliant,
 you should tell Flake8 to ignore these warnings.
 

+### Slices
+
+PEP 8 [recommends](https://www.python.org/dev/peps/pep-0008/#whitespace-in-expressions-and-statements)
+to treat ``:`` in slices as a binary operator with the lowest priority, and to
+leave an equal amount of space on either side, except if a parameter is omitted
+(e.g. ``ham[1 + 1 :]``). It also states that for extended slices, both ``:``
+operators have to have the same amount of spacing, except if a parameter is
+omitted (``ham[1 + 1 ::]``). *Black* enforces these rules consistently.
+
+This behaviour may raise ``E203 whitespace before ':'`` warnings in style guide
+enforcement tools like Flake8. Since ``E203`` 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
 ### Parentheses
 
 Some parentheses are optional in the Python grammar.  Any expression can


@@ -311,6 +332,11 @@ interesting cases:
 - `for (...) in (...):`
 - `assert (...), (...)`
 - `from X import (...)`
 - `for (...) in (...):`
 - `assert (...), (...)`
 - `from X import (...)`

+- assignments like:
+  - `target = (...)`
+  - `target: type = (...)`
+  - `some, *un, packing = (...)`
+  - `augmented += (...)`

 
 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
 
 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


@@ -368,9 +394,21 @@ Configuration:
 * `g:black_linelength` (defaults to `88`)
 * `g:black_virtualenv` (defaults to `~/.vim/black`)
 
 * `g:black_linelength` (defaults to `88`)
 * `g:black_virtualenv` (defaults to `~/.vim/black`)
 

-To install, copy the plugin from [vim/plugin/black.vim](https://github.com/ambv/black/tree/master/vim/plugin/black.vim).
+To install with [vim-plug](https://github.com/junegunn/vim-plug):
+
+```
+Plug 'ambv/black',
+```
+
+or with [Vundle](https://github.com/VundleVim/Vundle.vim):
+
+```
+Plugin 'ambv/black'
+```
+
+or you can copy the plugin from [plugin/black.vim](https://github.com/ambv/black/tree/master/plugin/black.vim).

 Let me know if this requires any changes to work with Vim 8's builtin
 Let me know if this requires any changes to work with Vim 8's builtin

-`packadd`, or Pathogen, or Vundle, and so on.
+`packadd`, or Pathogen, and so on.

 
 This plugin **requires Vim 7.0+ built with Python 3.6+ support**.  It
 needs Python 3.6 to be able to run *Black* inside the Vim process which
 
 This plugin **requires Vim 7.0+ built with Python 3.6+ support**.  It
 needs Python 3.6 to be able to run *Black* inside the Vim process which


@@ -381,7 +419,7 @@ Python version and automatically installs *Black*. You can upgrade it later
 by calling `:BlackUpgrade` and restarting Vim.
 
 If you need to do anything special to make your virtualenv work and
 by calling `:BlackUpgrade` and restarting Vim.
 
 If you need to do anything special to make your virtualenv work and

-install *Black* (for example you want to run a version from master), just
+install *Black* (for example you want to run a version from master),

 create a virtualenv manually and point `g:black_virtualenv` to it.
 The plugin will use it.
 
 create a virtualenv manually and point `g:black_virtualenv` to it.
 The plugin will use it.
 


@@ -401,6 +439,10 @@ Use [joslarson.black-vscode](https://marketplace.visualstudio.com/items?itemName
 
 Use [sublack plugin](https://github.com/jgirardet/sublack).
 
 
 Use [sublack plugin](https://github.com/jgirardet/sublack).
 

+### IPython Notebook Magic
+
+Use [blackcellmagic](https://github.com/csurfer/blackcellmagic).
+

 ### Other editors
 
 Atom/Nuclide integration is planned by the author, others will
 ### Other editors
 
 Atom/Nuclide integration is planned by the author, others will


@@ -448,9 +490,9 @@ location of the file depends on the black version and the system on which black
 is run. The file is non-portable. The standard location on common operating systems
 is:
 
 is run. The file is non-portable. The standard location on common operating systems
 is:
 

-* Windows: `C:\\Users\<username>\AppData\Local\black\black\Cache\<version>\cache.pkl`
-* macOS: `/Users/<username>/Library/Caches/black/<version>/cache.pkl`
-* Linux: `/home/<username>/.cache/black/<version>/cache.pkl`
+* Windows: `C:\\Users\<username>\AppData\Local\black\black\Cache\<version>\cache.<line-length>.pickle`
+* macOS: `/Users/<username>/Library/Caches/black/<version>/cache.<line-length>.pickle`
+* Linux: `/home/<username>/.cache/black/<version>/cache.<line-length>.pickle`

 
 
 ## Testimonials
 
 
 ## Testimonials


@@ -492,8 +534,8 @@ MIT
 
 ## Contributing to Black
 
 
 ## Contributing to Black
 

-In terms of inspiration, *Black* is about as configurable as *gofmt* and
-*rustfmt* are.  This is deliberate.
+In terms of inspiration, *Black* is about as configurable as *gofmt*.
+This is deliberate.

 
 Bug reports and fixes are always welcome!  However, before you suggest a
 new feature or configuration knob, ask yourself why you want it.  If it
 
 Bug reports and fixes are always welcome!  However, before you suggest a
 new feature or configuration knob, ask yourself why you want it.  If it


@@ -508,16 +550,69 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 ## Change Log
 
 
 ## Change Log
 

-### 18.4a3 (unreleased)
+### 18.5a0 (unreleased)
+
+* slices are now formatted according to PEP 8 (#178)
+
+* parentheses are now also managed automatically on the right-hand side
+  of assignments and return statements (#140)
+
+* math operators now use their respective priorities for delimiting multiline
+  expressions (#148)
+
+* empty parentheses in a class definition are now removed (#145, #180)
+
+* string prefixes are now standardized to lowercase and `u` is removed
+  on Python 3.6+ only code and Python 2.7+ code with the `unicode_literals`
+  future import (#188, #198, #199)
+
+* fixed an invalid trailing comma sometimes left in imports (#185)
+
+* fixed non-deterministic formatting when multiple pairs of removable parentheses
+  were used (#183)
+
+* fixed not splitting long from-imports with only a single name
+
+* fixed Python 3.6+ file discovery by also looking at function calls with
+  unpacking. This fixed non-deterministic formatting if trailing commas
+  where used both in function signatures with stars and function calls
+  with stars but the former would be reformatted to a single line.
+
+
+### 18.4a4
+
+* don't populate the cache on `--check` (#175)
+
+
+### 18.4a3

 
 * added a "cache"; files already reformatted that haven't changed on disk
   won't be reformatted again (#109)
 
 
 * added a "cache"; files already reformatted that haven't changed on disk
   won't be reformatted again (#109)
 

+* `--check` and `--diff` are no longer mutually exclusive (#149)
+

 * generalized star expression handling, including double stars; this
   fixes multiplication making expressions "unsafe" for trailing commas (#132)
 
 * generalized star expression handling, including double stars; this
   fixes multiplication making expressions "unsafe" for trailing commas (#132)
 

-* fix parsing of complex expressions after star and double stars in
-  function parameters (#2)
+* Black no longer enforces putting empty lines behind control flow statements
+  (#90)
+
+* Black now splits imports like "Mode 3 + trailing comma" of isort (#127)
+
+* fixed comment indentation when a standalone comment closes a block (#16, #32)
+
+* fixed standalone comments receiving extra empty lines if immediately preceding
+  a class, def, or decorator (#56, #154)
+
+* fixed `--diff` not showing entire path (#130)
+
+* fixed parsing of complex expressions after star and double stars in
+  function calls (#2)
+
+* fixed invalid splitting on comma in lambda arguments (#133)
+
+* fixed missing splits of ternary expressions (#141)
+

 
 ### 18.4a2
 
 
 ### 18.4a2
 


@@ -676,9 +771,12 @@ Maintained with [Carol Willing](mailto:carolcode@willingconsulting.com),
 Multiple contributions by:
 * [Anthony Sottile](mailto:asottile@umich.edu)
 * [Artem Malyshev](mailto:proofit404@gmail.com)
 Multiple contributions by:
 * [Anthony Sottile](mailto:asottile@umich.edu)
 * [Artem Malyshev](mailto:proofit404@gmail.com)

+* [Christian Heimes](mailto:christian@python.org)

 * [Daniel M. Capella](mailto:polycitizen@gmail.com)
 * [Eli Treuherz](mailto:eli.treuherz@cgi.com)
 * Hugo van Kemenade
 * [Ivan Katanić](mailto:ivan.katanic@gmail.com)
 * [Jonas Obrist](mailto:ojiidotch@gmail.com)
 * [Osaetin Daniel](mailto:osaetindaniel@gmail.com)
 * [Daniel M. Capella](mailto:polycitizen@gmail.com)
 * [Eli Treuherz](mailto:eli.treuherz@cgi.com)
 * Hugo van Kemenade
 * [Ivan Katanić](mailto:ivan.katanic@gmail.com)
 * [Jonas Obrist](mailto:ojiidotch@gmail.com)
 * [Osaetin Daniel](mailto:osaetindaniel@gmail.com)

+* [Sunil Kapil](mailto:snlkapil@gmail.com)
+* [Vishwas B Sharma](mailto:sharma.vishwas88@gmail.com)