Avoid unnecessary multiline parentheses

[Morriar]

Avoid unnecessary parentheses when autocorrecting multiline T.must calls without comments.

Before:

variant = (
  InventoryItemVariant.preload(:variant).where(inventory_item_id: @inventory_item_id).first!.variant
).not_nil!

After:

variant = InventoryItemVariant.preload(:variant).where(inventory_item_id: @inventory_item_id).first!.variant.not_nil!

Calls containing comments keep the grouped form so comments and internal indentation are preserved.

[egiurleo]

I believe this will fail the following case:

value = (
  <<~TEXT
    hello
  TEXT
).not_nil!

by converting it to value = <<~TEXT.not_nil!

argument.source is just the <<~TEXT portion of the heredoc so returning the replacement in this case truncates the rest of the heredoc. Probably worth adding a test?

[Morriar]

Good catch, I added a special case for heredoc. I decided to preserve the parenthesis around it to avoid messing with indentation.

So this:

foo = T.must(
  <<~FOO
    hello
  FOO
)

becomes this:

foo = (
  <<~FOO
    hello
  FOO
).not_nil!

instead of this:

foo = <<~FOO.not_nil!
    hello
  FOO