Bug #14584: Squigly heredoc with interpolation that has a string literal withe spaces gets incorrect value

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.5.0p0 (2017-12-25 revision 61468) [x86_64-darwin17]
• Backport: 2.3: REQUIRED, 2.4: REQUIRED, 2.5: DONE

[asterite (Ary Borenszweig)]

Given this program:

text1 = <<~FOO
  one#{"   two   "}
  FOO

text2 = <<~FOO
one#{"   two   "}
FOO

p text1
p text2

The output is:

"one two   \n"
"one   two   \n"

The two should be equal.

I think the problem happens because squigly heredoc will remove the first two spaces from each line in the heredoc, but it seems to also be removing it from literals inside interpolation inside a heredoc.

[sikachu (Prem Sichanugrist)]

👍 I can confirm this bug exists in 2.5.0p0.

Also, it seems like the number of spaces it's removing is based on the gutter size as well (which is expected?)

# two spaces gutter, four leading spaces in literal
<<~FOO
  two#{"    four    "}
FOO
#=> "two  four    \n"

# two spaces gutter, five leading spaces in literal
<<~FOO
  two#{"     five     "}
FOO
#=> "two   five     \n"

# three spaces gutter, five leading spaces in literal
<<~FOO
   three#{"     five     "}
FOO
#=> "three  five     \n"

I don't have enough Ruby lexer knowledge to fix this, so I hope someone will be able to spare their time taking care of this 🙇‍♂️

[asterite (Ary Borenszweig)]

Interestingly enough, it doesn't happen when you have:

text1 = <<~FOO
  one#{"   two   " * 1}
  FOO

So it seems Ruby does this only when the interpolation has a string literal, presumably to optimize that out and embed it into the resulting heredoc string.

[nobu (Nobuyoshi Nakada)]

• Related to Bug #11989: Dedenting interpolating heredoc can interpret escapes incorrectly added

[nobu (Nobuyoshi Nakada)]

• Description updated (diff)
• Backport changed from 2.3: UNKNOWN, 2.4: UNKNOWN, 2.5: UNKNOWN to 2.3: REQUIRED, 2.4: REQUIRED, 2.5: REQUIRED

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset trunk|r62724.

---

parse.y: fix interpolated string literal dedent

• parse.y (heredoc_dedent): fix interpolated string literal dedent,
  remove indentations from only nodes with the newline flag.
  [ruby-core:85983] [Bug #14584]

• parse.y (here_document): set the newline flag on literal string
  nodes starting at the beginning of line.

[naruse (Yui NARUSE)]

• Backport changed from 2.3: REQUIRED, 2.4: REQUIRED, 2.5: REQUIRED to 2.3: REQUIRED, 2.4: REQUIRED, 2.5: DONE

ruby_2_5 r62909 merged revision(s) 62723,62724.