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>
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