[clang-format] `BreakAfterAttributes` has strange interaction with `= delete`

[Eisenwave]

https://godbolt.org/z/cYYaPPGor

Consider the original code (this is how I want it to look)

[[deprecated]]
void f() = delete;

With

BreakAfterAttributes: Always
BasedOnStyle: WebKit

I get

[[deprecated]]
void f()
    = delete;

I don't why it breaks the = delete onto the next line. This doesn't happen with BreakAfterAttributes: Never, so it seems more like a bug than intentional formatting.

[llvmbot]

@llvm/issue-subscribers-clang-format

Author: Jan Schultke (Eisenwave)

https://godbolt.org/z/cYYaPPGor

Consider the original code (this is how I want it to look)

[[deprecated]]
void f() = delete;

With

BreakAfterAttributes: Always
BasedOnStyle: WebKit

I get

[[deprecated]]
void f()
    = delete;

I don't why it breaks the = delete onto the next line. This doesn't happen with BreakAfterAttributes: Never, so it seems more like a bug than intentional formatting.

[owenca]

Instead, it looks like a bug with BreakBeforeBinaryOperators: All:

$ clang-format -version
clang-format version 20.1.8
$ cat a.cc
[[deprecated]]
void f() = delete;
$ clang-format -style='{BreakBeforeBinaryOperators: All}' a.cc
[[deprecated]]
void f()
    = delete;