incorrect line break on assignment of function

[matthargett]

exports.ScalarLeafsRule = function(context)
        return {
                Field = function(_self, node)
                        local type_ = context:getType()
                        local selectionSet = node.selectionSet
                        if type_ then
                                if isLeafType(getNamedType(type_)) then
                                        if selectionSet then
                                                local fieldName = node.name.value
                                                local typeStr = inspect(type_)
                                                context:reportError(
                                                        GraphQLError.new(
                                                                ('Field "%s" must not have a selection since type "%s" has no subfields.'):format(
                                                                        fieldName,
                                                                        typeStr
                                                                ),
                                                                selectionSet
                                                        )
                                                )
                                        end
                                elseif not selectionSet then
                                        local fieldName = node.name.value
                                        local typeStr = inspect(type_)
                                        context:reportError(
                                                GraphQLError.new(
                                                        ('Field "%s" of type "%s" must have a selection of subfields. Did you mean "%s { ... }"?'):format(
                                                                fieldName,
                                                                typeStr,
                                                                fieldName
                                                        ),
                                                        node
                                                )
                                        )
                                end
                        end
                end,
        }
end

[JohnnyMorganz]

[Copying message from offline]
The reason this is hanging is because it produces less lines...
That is because of this expression

context:reportError(
    GraphQLError.new(
        ('Field "%s" of type "%s" must have a selection of subfields. Did you mean "%s { ... }"?'):format(
            fieldName,
            typeStr,
            fieldName
        ),
        node
    )
)

Because, when we hang at the equals token, the block gets indented a level further, and the extra indentation causes a re-formatting to

context:reportError(
    GraphQLError.new(
        (
            'Field "%s" of type "%s" must have a selection of subfields. Did you mean "%s { ... }"?'
        ):format(fieldName, typeStr, fieldName),
        node
    )
)

which... technically has less lines

The reason it only gets reformatted when the block is indented is because the parentheses expression finishes just before the char limit, and when we indent it now goes over it.

---

One potential fix we could do here is to just prevent the expression ("str"):call from ever expanding the parentheses, as it provides no added benefit. It doesn't fix the underlying cause, but it should stop this from hanging