Bug #15337: String#each_grapheme_cluster wrongly splits "\r\n"

• Status: Closed
• Assignee: naruse (Yui NARUSE)
• Target version: 2.6
• ruby -v: ruby 2.6.0dev (2018-11-24 trunk 65950) [x86_64-linux]
• Backport: 2.3: DONTNEED, 2.4: REQUIRED, 2.5: DONE

[duerst (Martin Dürst)]

The method each_grapheme_cluster on the String class wrongly splits CRLF into two clusters, as follows:

[duerst@stazersee ruby2]$ ./ruby -e 'puts "\r\n".each_grapheme_cluster.to_a.inspect'
["\r", "\n"]
[duerst@stazersee ruby2]$ ./ruby -v
ruby 2.6.0dev (2018-11-24 trunk 65950) [x86_64-linux]

The expected result in the above case is:

["\r\n"]

Except for the test cases that contain (unpaired) surrogates, which don't apply for us, this is the only test case that fails when testing with the data at http://www.unicode.org/Public/10.0.0/ucd/auxiliary/GraphemeBreakTest.txt. I have a test script using all that data that I plan to commit as soon as this bug is dealt with.

I would like to make sure that this is correct for Unicode 10.0.0 before moving to Unicode 11.0.0. In both specifications, the CRLF case is listed explicitly first in the specification.

I will try to find out how to fix this by myself, but would definitely appreciate help.

[duerst (Martin Dürst)]

• Blocks Feature #14802: Update Unicode data to Unicode Version 11.0.0 added

[naruse (Yui NARUSE)]

• Status changed from Open to Closed

Applied in changeset trunk|r65954.

---

Don't use single byte optimization on grapheme clusters

Unicode Text Segmentation considers CRLF as a character. [Bug #15337]

[duerst (Martin Dürst)]

Once we have a fix for this bug, it should be backported to all the versions that implement \X and that we still support.

[naruse (Yui NARUSE)]

• Backport changed from 2.3: UNKNOWN, 2.4: UNKNOWN, 2.5: UNKNOWN to 2.3: DONTNEED, 2.4: REQUIRED, 2.5: REQUIRED

[nagachika (Tomoyuki Chikanaga)]

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

ruby_2_5 r66073 merged revision(s) 65954,65955,65958.