ruff/crates/ruff_python_formatter/src/statement/stmt_if.rs
konsti 9a817a2922
Insert empty line between suite and alternative branch after def/class (#12294)
When there is a function or class definition at the end of a suite
followed by the beginning of an alternative block, we have to insert a
single empty line between them.

In the if-else-statement example below, we insert an empty line after
the `foo` in the if-block, but none after the else-block `foo`, since in
the latter case the enclosing suite already adds empty lines.

```python
if sys.version_info >= (3, 10):
    def foo():
        return "new"
else:
    def foo():
        return "old"
class Bar:
    pass
```

To do so, we track whether the current suite is the last one in the
current statement with a new option on the suite kind.

Fixes #12199

---------

Co-authored-by: Micha Reiser <micha@reiser.io>
2024-07-15 12:59:33 +02:00

113 lines
3.5 KiB
Rust

use ruff_formatter::{format_args, write};
use ruff_python_ast::{AnyNodeRef, ElifElseClause, StmtIf};
use ruff_text_size::Ranged;
use crate::expression::maybe_parenthesize_expression;
use crate::expression::parentheses::Parenthesize;
use crate::prelude::*;
use crate::statement::clause::{clause_body, clause_header, ClauseHeader};
use crate::statement::suite::SuiteKind;
#[derive(Default)]
pub struct FormatStmtIf;
impl FormatNodeRule<StmtIf> for FormatStmtIf {
fn fmt_fields(&self, item: &StmtIf, f: &mut PyFormatter) -> FormatResult<()> {
let StmtIf {
range: _,
test,
body,
elif_else_clauses,
} = item;
let comments = f.context().comments().clone();
let trailing_colon_comment = comments.dangling(item);
write!(
f,
[
clause_header(
ClauseHeader::If(item),
trailing_colon_comment,
&format_args![
token("if"),
space(),
maybe_parenthesize_expression(test, item, Parenthesize::IfBreaks),
],
),
clause_body(
body,
SuiteKind::other(elif_else_clauses.is_empty()),
trailing_colon_comment
),
]
)?;
let mut last_node = body.last().unwrap().into();
for clause in elif_else_clauses {
format_elif_else_clause(
clause,
f,
Some(last_node),
SuiteKind::other(clause == elif_else_clauses.last().unwrap()),
)?;
last_node = clause.body.last().unwrap().into();
}
Ok(())
}
}
/// Extracted so we can implement `FormatElifElseClause` but also pass in `last_node` from
/// `FormatStmtIf`
pub(crate) fn format_elif_else_clause(
item: &ElifElseClause,
f: &mut PyFormatter,
last_node: Option<AnyNodeRef>,
suite_kind: SuiteKind,
) -> FormatResult<()> {
let ElifElseClause {
range: _,
test,
body,
} = item;
let comments = f.context().comments().clone();
let trailing_colon_comment = comments.dangling(item);
let leading_comments = comments.leading(item);
write!(
f,
[
clause_header(
ClauseHeader::ElifElse(item),
trailing_colon_comment,
&format_with(|f: &mut PyFormatter| {
f.options()
.source_map_generation()
.is_enabled()
.then_some(source_position(item.start()))
.fmt(f)?;
if let Some(test) = test {
write!(
f,
[
token("elif"),
space(),
maybe_parenthesize_expression(test, item, Parenthesize::IfBreaks),
]
)
} else {
token("else").fmt(f)
}
}),
)
.with_leading_comments(leading_comments, last_node),
clause_body(body, suite_kind, trailing_colon_comment),
f.options()
.source_map_generation()
.is_enabled()
.then_some(source_position(item.end()))
]
)
}