Feature Request: Vertical semicolon when wrapping function chains

[wormingdead]

I ended up writing this feature request formatted like the Rustfmt options docs. Please let me know if more information is needed or if I somehow missed that this option already exists.

fn_chain_vertical_semicolon

Vertically wrap the semicolon at the end of a vertical function chain.

Pros

• Easier to visually scan the leftmost character to see when the method calls stop and the semicolon ends the statement.
• IDEs that support single-line commenting don't have to be corrected after commenting out the last line.
  • e.g. in the false example, an IDE may replace .dolor(); with // .dolor(); and comment out the semicolon causing an error.

Cons

• Adds a basically empty line, making code taller than necessary.

---

• Default: I don't know how this is decided. As it is currently unimplemented, the default is false.
• Possible Values: true, false

false:

fn main() {
    lorem
        .ipsum()
        .dolor();
}

true:

fn main() {
    lorem
        .ipsum()
        .dolor()
        ;
}

[calebcartwright]

Thanks for sharing your idea. I'll leave this open for a bit, but to be fully transparent, this isn't something we the rustfmt team will ever work on and I don't particularly want to solicit contributions either because I don't think it's worth the extra config option.

If this is something you feel strongly enough about you're welcome to submit a pull request which we'd consider, but otherwise this is unlikely to ever come to fruition.