Poor TAIT formatting with `version = "Two"`: `+` line breaks are not block indented

[chitoyuu]

Currently on 1.4.37-nightly (dfc5add 2021-10-13), with version = "Two" and all other options left at default, this:

pub type Iter<'a, D> = impl DoubleEndedIterator<Item = (SomethingSomethingSomethingLongType<D>)> + ExactSizeIterator + 'a;

is formatted to:

pub type Iter<'a, D> = impl DoubleEndedIterator<Item = (SomethingSomethingSomethingLongType<D>)>
+ ExactSizeIterator
+ 'a;

...whereas on stable, the same code is formatted to the more familiar and (subjectively) more pleasing:

pub type Iter<'a, D> = impl DoubleEndedIterator<Item = (SomethingSomethingSomethingLongType<D>)>
    + ExactSizeIterator
    + 'a;

...with block indentation for the broken lines.

[calebcartwright]

I can't reproduce this with default behavior, and have to change the default value of the version config option to Two in order to reproduce.

That is of course something we need to fix, but I need to get some clarity on whether this can actually be produced with all defaults. Can you share your rustfmt config file, and/or share output from running rustfmt in verbose mode?

[chitoyuu]

I can't reproduce this with default behavior, and have to change the default value of the version config option to Two in order to reproduce.

My bad. My rustfmt.toml is a single line version = "Two". When I said "by default" I was having "version 2 default" in mind. I have updated the issue to mention this. Sorry I didn't make it clear enough the first time.

[calebcartwright]

No worries, thanks for clarifying!

[karyon]

fwiw, this is the PR/diff that has introduced this: 1643d72#diff-ed12f5ea605f23bb4d26cc65778e3daff9db3eec40e2abfc82beafca130a99a0R751.

#4373 seems related.