Issue #10893 has been updated by Tomoyuki Chikanaga.

Backport changed from 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: DONE to 2.0.0: DONTNEED, 2.1: DONTNEED, 2.2: DONE

```
% ruby -ve '$/="\n".encode("UTF-8"); p "abc\r\n".encode("utf-32be").chomp'
ruby 2.0.0p598 (2014-11-13 revision 48408) [x86_64-darwin13.4.0]
"abc"
```
```
% ruby -ve '$/="\n".encode("UTF-8"); p "abc\r\n".encode("utf-32be").chomp'
ruby 2.1.5p299 (2015-02-19 revision 49651) [x86_64-darwin13.0]
"abc"
```

----------------------------------------
Bug #10893: String#chomp (and chomp!) with a UTF-8 record separator results in Encoding::CompatibilityError
https://bugs.ruby-lang.org/issues/10893#change-51639

* Author: Benoit Daloze
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-02-23 trunk 49693) [x86_64-linux]
* Backport: 2.0.0: DONTNEED, 2.1: DONTNEED, 2.2: DONE
----------------------------------------
Reproducing code:

    $/="\n".encode("UTF-8"); p "abc\r\n".encode("utf-32be").chomp

The encode to UTF-8 is to make sure the encoding is consistent across versions, but in recent rubies it is not necessary to trigger the bug.

    ruby 2.3.0dev (2015-02-23 trunk 49693) [x86_64-linux]
    -e:1:in `chomp': incompatible character encodings: UTF-32BE and UTF-8 (Encoding::CompatibilityError)
    	from -e:1:in `<main>'


    ruby 2.2.0p0 (2014-12-25 revision 49005) [x86_64-linux]
    -e:1:in `chomp': incompatible character encodings: UTF-32BE and UTF-8 (Encoding::CompatibilityError)
    	from -e:1:in `<main>'

    ruby 2.1.3p242 (2014-09-19 revision 47630) [x86_64-linux]
    "abc"




-- 
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