This file is indexed.

/usr/share/zsh/help/shift is in zsh-common 5.1.1-1ubuntu2.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

1
2
3
4
5
6
7
8
shift [ -p ] [ n ] [ name ... ]
       The  positional  parameters  ${n+1}  ...  are renamed to $1 ...,
       where n is an arithmetic expression that defaults to 1.  If  any
       names  are  given  then  the arrays with these names are shifted
       instead of the positional parameters.

       If the option -p is given arguments are instead removed (popped)
       from the end rather than the start of the array.