// rustfmt-single_line_let_else_max_width: 100 fn main() { // Although this won't compile it still parses so make sure we can format empty else blocks let Some(x) = opt else {}; // let-else may be formatted on a single line if they are "short" // and only contain a single expression let Some(x) = opt else { return }; let Some(x) = opt else { return }; let Some(x) = opt else { return; }; let Some(x) = opt else { // nope return; }; let Some(x) = opt else { let y = 1; return y }; let Some(x) = y.foo("abc", fairly_long_identifier, "def", "123456", "string", "cheese") else { bar() }; let Some(x) = abcdef().foo("abc", some_really_really_really_long_ident, "ident", "123456").bar().baz().qux("fffffffffffffffff") else { foo_bar() }; } fn with_comments_around_else_keyword() { let Some(x) = opt /* pre else keyword block-comment */ else { return }; let Some(x) = opt else /* post else keyword block-comment */ { return }; let Some(x) = opt /* pre else keyword block-comment */ else /* post else keyword block-comment */ { return }; let Some(x) = opt // pre else keyword line-comment else { return }; let Some(x) = opt else // post else keyword line-comment { return }; let Some(x) = opt // pre else keyword line-comment else // post else keyword line-comment { return }; } fn unbreakable_initializer_expr_pre_formatting_let_else_length_near_max_width() { // Pre Formatting: // The length of `(indent)let pat = init else block;` is 100 (max_width) // Post Formatting: // The formatting is left unchanged! let Some(x) = some_really_really_really_really_really_really_really_long_name_A else { return }; // Pre Formatting: // The length of `(indent)let pat = init else block;` is 100 (max_width) // Post Formatting: // The else keyword and opening brace remain on the same line as the initializer expr, // and the else block is formatted over multiple lines because we can't fit the // else block on the same line as the initializer expr. let Some(x) = some_really_really_really_really_really_really_really_long_name___B else {return}; // Pre Formatting: // The length of `(indent)let pat = init else block;` is 100 (max_width) // Post Formatting: // The else keyword and opening brace remain on the same line as the initializer expr, // and the else block is formatted over multiple lines because we can't fit the // else block on the same line as the initializer expr. let Some(x) = some_really_really_really_really_long_name_____C else {some_divergent_function()}; // Pre Formatting: // The length of `(indent)let pat = init else block;` is 101 (> max_width) // Post Formatting: // The else keyword and opening brace remain on the same line as the initializer expr, // and the else block is formatted over multiple lines because we can't fit the // else block on the same line as the initializer expr. let Some(x) = some_really_really_really_really_really_really_really_long_name__D else { return }; } fn unbreakable_initializer_expr_pre_formatting_length_up_to_opening_brace_near_max_width() { // Pre Formatting: // The length of `(indent)let pat = init else {` is 99 (< max_width) // Post Formatting: // The else keyword and opening brace remain on the same line as the initializer expr, // and the else block is formatted over multiple lines because we can't fit the // else block on the same line as the initializer expr. let Some(x) = some_really_really_really_really_really_really_really_really_long_name___E else {return}; // Pre Formatting: // The length of `(indent)let pat = init else {` is 101 (> max_width) // Post Formatting: // The else keyword and opening brace cannot fit on the same line as the initializer expr. // They are formatted on the next line. let Some(x) = some_really_really_really_really_really_really_really_really_long_name_____F else {return}; } fn unbreakable_initializer_expr_pre_formatting_length_through_initializer_expr_near_max_width() { // Pre Formatting: // The length of `(indent)let pat = init` is 99 (< max_width) // Post Formatting: // The else keyword and opening brace cannot fit on the same line as the initializer expr. // They are formatted on the next line. let Some(x) = some_really_really_really_really_really_really_really_really_really_long_name___G else {return}; // Pre Formatting: // The length of `(indent)let pat = init` is 100 (max_width) // Post Formatting: // Break after the `=` and put the initializer expr on it's own line. // Because the initializer expr is multi-lined the else is placed on it's own line. let Some(x) = some_really_really_really_really_really_really_really_really_really_long_name____H else {return}; // Pre Formatting: // The length of `(indent)let pat = init` is 109 (> max_width) // Post Formatting: // Break after the `=` and put the initializer expr on it's own line. // Because the initializer expr is multi-lined the else is placed on it's own line. // The initializer expr has a length of 91, which when indented on the next line // The `(indent)init` line has a length of 99. This is the max length that the `init` can be // before we start running into max_width issues. I suspect this is because the shape is // accounting for the `;` at the end of the `let-else` statement. let Some(x) = some_really_really_really_really_really_really_really_really_really_really_long_name______I else {return}; // Pre Formatting: // The length of `(indent)let pat = init` is 110 (> max_width) // Post Formatting: // Max length issues prevent us from formatting. // The initializer expr has a length of 92, which if it would be indented on the next line // the `(indent)init` line has a length of 100 which == max_width of 100. // One might expect formatting to succeed, but I suspect the reason we hit max_width issues is // because the Shape is accounting for the `;` at the end of the `let-else` statement. let Some(x) = some_really_really_really_really_really_really_really_really_really_really_really_long_nameJ else {return}; } fn long_patterns() { let Foo {x: Bar(..), y: FooBar(..), z: Baz(..)} = opt else { return; }; // with version=One we don't wrap long array patterns let [aaaaaaaaaaaaaaaa, bbbbbbbbbbbbbbb, cccccccccccccccccc, dddddddddddddddddd] = opt else { return; }; let ("aaaaaaaaaaaaaaaaaaa" | "bbbbbbbbbbbbbbbbb" | "cccccccccccccccccccccccc" | "dddddddddddddddd" | "eeeeeeeeeeeeeeee") = opt else { return; }; let Some(Ok((Message::ChangeColor(super::color::Color::Rgb(r, g, b)), Point { x, y, z }))) = opt else { return; }; } fn with_trailing_try_operator() { // Currently the trailing ? forces the else on the next line // This may be revisited in style edition 2024 let Some(next_bucket) = ranking_rules[cur_ranking_rule_index].next_bucket(ctx, logger, &ranking_rule_universes[cur_ranking_rule_index])? else { return }; // Maybe this is a workaround? let Ok(Some(next_bucket)) = ranking_rules[cur_ranking_rule_index].next_bucket(ctx, logger, &ranking_rule_universes[cur_ranking_rule_index]) else { return }; } fn issue5901() { #[cfg(target_os = "linux")] let Some(x) = foo else { todo!() }; #[cfg(target_os = "linux")] // Some comments between attributes and let-else statement let Some(x) = foo else { todo!() }; #[cfg(target_os = "linux")] #[cfg(target_arch = "x86_64")] let Some(x) = foo else { todo!() }; // The else block will be multi-lined because attributes and comments before `let` // are included when calculating max width #[cfg(target_os = "linux")] #[cfg(target_arch = "x86_64")] // Some comments between attributes and let-else statement let Some(x) = foo() else { todo!() }; }