]> 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:

Document disabling E704 (#3888)
[etc/vim.git] / docs / the_black_code_style / future_style.md
index 6d289d460a76c10db74343e991f3dfc26e075ab7..861bb64bff4d10016fde5db5230d887fbca364ec 100644 (file)
@@ -47,11 +47,13 @@ with contextlib.ExitStack() as exit_stack:
     ...
 ```
 
+(labels/preview-style)=
+
 ## Preview style
 
 Experimental, potentially disruptive style changes are gathered under the `--preview`
 CLI flag. At the end of each year, these changes may be adopted into the default style,
-as described in [The Black Code Style](./index.rst). Because the functionality is
+as described in [The Black Code Style](index.md). Because the functionality is
 experimental, feedback and issue reports are highly encouraged!
 
 ### Improved string processing
@@ -62,3 +64,99 @@ plain strings. User-made splits are respected when they do not exceed the line l
 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).
+
+### Improved line breaks
+
+For assignment expressions, _Black_ now prefers to split and wrap the right side of the
+assignment instead of left side. For example:
+
+```python
+some_dict[
+    "with_a_long_key"
+] = some_looooooooong_module.some_looooooooooooooong_function_name(
+    first_argument, second_argument, third_argument
+)
+```
+
+will be changed to:
+
+```python
+some_dict["with_a_long_key"] = (
+    some_looooooooong_module.some_looooooooooooooong_function_name(
+        first_argument, second_argument, third_argument
+    )
+)
+```
+
+### Improved parentheses management
+
+For dict literals with long values, they are now wrapped in parentheses. Unnecessary
+parentheses are now removed. For example:
+
+```python
+my_dict = {
+    "a key in my dict": a_very_long_variable
+    * and_a_very_long_function_call()
+    / 100000.0,
+    "another key": (short_value),
+}
+```
+
+will be changed to:
+
+```python
+my_dict = {
+    "a key in my dict": (
+        a_very_long_variable * and_a_very_long_function_call() / 100000.0
+    ),
+    "another key": short_value,
+}
+```
+
+### Improved multiline string handling
+
+_Black_ is smarter when formatting multiline strings, especially in function arguments,
+to avoid introducing extra line breaks. Previously, it would always consider multiline
+strings as not fitting on a single line. With this new feature, _Black_ looks at the
+context around the multiline string to decide if it should be inlined or split to a
+separate line. For example, when a multiline string is passed to a function, _Black_
+will only split the multiline string if a line is too long or if multiple arguments are
+being passed.
+
+For example, _Black_ will reformat
+
+```python
+textwrap.dedent(
+    """\
+    This is a
+    multiline string
+"""
+)
+```
+
+to:
+
+```python
+textwrap.dedent("""\
+    This is a
+    multiline string
+""")
+```
+
+And:
+
+```python
+MULTILINE = """
+foobar
+""".replace(
+    "\n", ""
+)
+```
+
+to:
+
+```python
+MULTILINE = """
+foobar
+""".replace("\n", "")
+```