The idea behind this change is that we stop looking into previous body to determine if there should be a blank before a function or class definition.
Input:
```python
import sys
if sys.version_info > (3, 7):
class Nested1:
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
class Nested2:
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
if sys.version_info > (3, 7):
def nested1():
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
def nested2():
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
```
Stable style
```python
import sys
if sys.version_info > (3, 7):
class Nested1:
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
class Nested2:
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
if sys.version_info > (3, 7):
def nested1():
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
def nested2():
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
```
In the stable formatting, we have a blank line sometimes, not depending on the previous statement on the same level, but on the last (potentially nested) statement in the previous body.
#2783/#3564 fixes this for classes in preview style:
```python
import sys
if sys.version_info > (3, 7):
class Nested1:
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
class Nested2:
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
if sys.version_info > (3, 7):
def nested1():
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
def nested2():
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
```
This PR additionally fixes this for function definitions:
```python
if sys.version_info > (3, 7):
if sys.platform == "win32":
assignment = 1
def function_definition(self): ...
def f1(self) -> str: ...
if sys.platform != "win32":
def function_definition(self): ...
assignment = 1
def f2(self) -> str: ...
if sys.version_info > (3, 8):
if sys.platform == "win32":
assignment = 1
def function_definition(self): ...
class F1: ...
if sys.platform != "win32":
def function_definition(self): ...
assignment = 1
class F2: ...
```
You can see the effect of this change on typeshed in https://github.com/konstin/typeshed/pull/1/files. As baseline, the preview mode changes without this PR are at https://github.com/konstin/typeshed/pull/2.
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
* Add option to skip the first line in source file
This commit adds a CLi option to skip the first line in the source
files, just like the Cpython command line allows [1]. By enabling the
flag, using `-x` or `--skip-source-first-line`, the first line is
removed temporarilly while the remaining contents are formatted. The
first line is added back before returning the formatted output.
[1]: https://docs.python.org/dev/using/cmdline.html#cmdoption-x
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Add tests for `--skip-source-first-line` option
When the flag is disabled (default), black formats the entire source
file, as in every line. In the other hand, if the flag is enabled, by
using `-x` or `--skip-source-first-line`, the first line is retained
while the rest of the source is formatted and then is added back.
These tests use an empty Python file that contains invalid syntax in
its first line (`invalid_header.py`, at `miscellaneous/`). First,
Black is invoked without enabling the flag which should result in an
exit code different than 0. When the flag is enabled, Black is
expected to return a successful exit code and the header is expected
to be retained (even if its not valid Python syntax).
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Support skip source first line option for blackd
The recently added option can be added as an acceptable header for
blackd. The arguments are passed in such a way that using the new
header will activate the skip source first line behaviour as expected
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Add skip source first line option to blackd docs
The new option can be passed to blackd as a header. This commit
updates the blackd docs to include the new header.
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Update CHANGES.md
Include the new Black option to skip the first line of source code in
the configuration section
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Update skip first line test including valid syntax
Including valid Python syntax help us make sure that the file is still
actually valid after skipping the first line of the source file (which
contains invalid Python syntax)
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Skip first source line at `format_file_in_place`
Instead of skipping the first source line at `format_file_contents`,
do it before. This allow us to find the correct newline and encoding
on the actual source code (everything that's after the header).
This change is also applied at Blackd: take the header before passing
the source to `format_file_contents` and put the header back once we
get the formatted result.
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Test output newlines when skipping first line
When skipping the first line of source code, the reference newline must
be taken from the second line of the file instead of the first one, in
case that the file mixes more than one kind of newline character
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Test that Blackd also skips first line correctly
Simliarly to the Black tests, we first compare that Blackd fails when
the first line is invalid Python syntax and then check that the result
is the expected when tha flag is activated
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
* Use the content encoding to decode the header
When decoding the header to put it back at the top of the contents of
the file, use the same encoding used in the content. This should be a
better "guess" that using the default value
Signed-off-by: Antonio Ossa Guerra <aaossa@uc.cl>
uR is not a legal string prefix, so this test breaks (AssertionError:
cannot use --safe with this file; failed to parse source file AST:
invalid syntax) if changed to one in which the file is changed. I've
changed the last test to have u alone, and added an R to the test above
instead.
The former was a regression I introduced a long time ago. To avoid
changing the stable style too much, the regression is only fixed if
--preview is enabled
Annoyingly enough, as we currently always enforce a second format pass if
changes were made, there's no good way to prove the existence of the
docstring quote normalization instability issue. For posterity, here's
one failing example:
--- source
+++ first pass
@@ -1,7 +1,7 @@
def some_function(self):
- ''''<text here>
+ """ '<text here>
<text here, since without another non-empty line black is stable>
- '''
+ """
pass
--- first pass
+++ second pass
@@ -1,7 +1,7 @@
def some_function(self):
- """ '<text here>
+ """'<text here>
<text here, since without another non-empty line black is stable>
"""
pass
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
