[ruby-core:98843] [Ruby master Bug#16966] Unexpected behavior of sort method

Issue #16966 has been updated by mame (Yusuke Endoh).

Status changed from Open to Rejected

It is a bug of the book.  Please report it to the author :-)

There is no guarantee about which `x` or `y` accepts each element.  The following code will work as expected.

```
[1,100,42,23,26,1000].sort {|x,y| x==42 ? 1 : y==42 ? -1 : x<=>y } #=> [1, 23, 26, 100, 1000, 42]
```

----------------------------------------
Bug #16966: Unexpected behavior of sort method
https://bugs.ruby-lang.org/issues/16966#change-86206

* Author: kk (Kirill /)
* Status: Rejected
* Priority: Normal
* ruby -v: 2.7.0
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN
----------------------------------------
Hey there

I've been going through the old ruby cook book from 2015 which uses ruby 2.1.

It has the following example of using sort method

``` ruby
[1,100,42,23,26,1000].sort {|x,y| x==42 ? 1 : x<=>y }
```
 

It's supposed to return `[1, 23, 26, 100, 10000, 42]`

-
So, I tried this with ruby 2.7.0 and it returned `[1, 23, 26, 42, 100, 1000]`

Same story with 2.6.5


-
If we try a different array `[1,2,42,46,22,33].sort {|x,y| x==42 ? 1 : x<=>y }`  It'll return  `[1, 2, 22, 33, 46, 42]` as expected with 42 at the end.

---Files--------------------------------
Screenshot 2020-06-16 at 15.09.41.png (151 KB)


-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:[e-mail]?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>