Motion with Unicode combining characters doesn't work

[sindikat]

Issue type

• Bug report

Environment

Emacs version: GNU Emacs 25.2.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.22.12) of 2017-05-08 Operating System: Ubuntu 17.04 Evil version: evil-git-0b4f0a69 Evil installation type: MELPA (Spacemacs) Graphical/Terminal: Graphical Terminal multiplexer: N/A

Reproduction steps

• Start Emacs
• Switch to scratch buffer
• Paste this text verbatim: naïve
• Put cursor at the beginning of the word
• Press vlly to try to yank naï

Expected behavior

The i with a diacritic is not a unicode character ï (LATIN SMALL LETTER I WITH DIAERESIS), but 2 characters i and ̈ (COMBINING DIAERESIS). Evil should yank naï, but yanks nai.

Actual behavior

Further notes

See also: https://emacs.stackexchange.com/q/18617/3972

[ninrod]

@sindikat, this is possibly related to #726