]> git.madduck.net Git - etc/vim.git/blobdiff - docs/the_black_code_style/future_style.md

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:

Fix type annotation for gitignore pathspec (#3416)
[etc/vim.git] / docs / the_black_code_style / future_style.md
index fab4bca120e634f26ec79ef4de9412c2de6196fa..17b7eef092f0179f53401e4521fb0e4bc214d0cc 100644 (file)
@@ -23,10 +23,10 @@ So _Black_ will eventually format it like this:
 
 ```py3
 with \
-     make_context_manager(1) as cm1, \
-     make_context_manager(2) as cm2, \
-     make_context_manager(3) as cm3, \
-     make_context_manager(4) as cm4 \
+     make_context_manager1() as cm1, \
+     make_context_manager2() as cm2, \
+     make_context_manager3() as cm3, \
+     make_context_manager4() as cm4 \
 :
     ...  # backslashes and an ugly stranded colon
 ```
@@ -34,6 +34,19 @@ with \
 Although when the target version is Python 3.9 or higher, _Black_ will use parentheses
 instead since they're allowed in Python 3.9 and higher.
 
+An alternative to consider if the backslashes in the above formatting are undesirable is
+to use {external:py:obj}`contextlib.ExitStack` to combine context managers in the
+following way:
+
+```python
+with contextlib.ExitStack() as exit_stack:
+    cm1 = exit_stack.enter_context(make_context_manager1())
+    cm2 = exit_stack.enter_context(make_context_manager2())
+    cm3 = exit_stack.enter_context(make_context_manager3())
+    cm4 = exit_stack.enter_context(make_context_manager4())
+    ...
+```
+
 ## Preview style
 
 Experimental, potentially disruptive style changes are gathered under the `--preview`
@@ -50,26 +63,47 @@ limit. Line continuation backslashes are converted into parenthesized strings.
 Unnecessary parentheses are stripped. The stability and status of this feature is
 tracked in [this issue](https://github.com/psf/black/issues/2188).
 
-### Removing newlines in the beginning of code blocks
+### Improved empty line management
 
-_Black_ will remove newlines in the beginning of new code blocks, i.e. when the
-indentation level is increased. For example:
+1.  _Black_ will remove newlines in the beginning of new code blocks, i.e. when the
+    indentation level is increased. For example:
 
-```python
-def my_func():
+    ```python
+    def my_func():
 
-    print("The line above me will be deleted!")
-```
+        print("The line above me will be deleted!")
+    ```
 
-will be changed to:
+    will be changed to:
+
+    ```python
+    def my_func():
+        print("The line above me will be deleted!")
+    ```
+
+    This new feature will be applied to **all code blocks**: `def`, `class`, `if`,
+    `for`, `while`, `with`, `case` and `match`.
+
+2.  _Black_ will enforce empty lines before classes and functions with leading comments.
+    For example:
+
+    ```python
+    some_var = 1
+    # Leading sticky comment
+    def my_func():
+        ...
+    ```
+
+    will be changed to:
+
+    ```python
+    some_var = 1
 
-```python
-def my_func():
-    print("The line above me will be deleted!")
-```
 
-This new feature will be applied to **all code blocks**: `def`, `class`, `if`, `for`,
-`while`, `with`, `case` and `match`.
+    # Leading sticky comment
+    def my_func():
+        ...
+    ```
 
 ### Improved parentheses management