This is a duplicate to all the letter shift/caesar ciphers.

Coffescript Translation Kumited! please accept :D

Java translation Kumited! please accept :D

There is a test case for upper letter Z missing.

Input: Quick brown fox jumps over the lazy dog ,
Expected Output: Rvjdl cspxo gpy kvnqt pwfs uif mbaz eph ,
Actual Output: Rvjdl cspxo gpy kvnqt pwfs uif mbаz eph

so expected output and actual output are identical, why it gives me an error?
all test cases work out fine, but this.
Is it some bug?

I think some random test cases should be added.

In the Haskell version: You don't check for other ASCII characters, like:

> import Data.Char
> filter isAscii $ map chr [0 .. 400]
"\NUL\SOH\STX\ETX\EOT\ENQ\ACK\a\b\t\n\v\f\r\SO\SI\DLE\DC1\DC2\DC3\DC4\NAK\SYN\ETB\CAN\EM\SUB\ESC\FS\GS\RS\US !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\DEL"

All current solutions ignore this, which works for sentences with spaces as seperators, but nothing else. To be honest, that's exactly why you don't use your solution to build test cases.