Add support for expanding Pointer slices in debugger

[ishankhare07]

What did you do? (required: The issue will be closed when not provided)

I tried using :GoDebugStart for the following program and the breakpoints at line 14 and 19

    1 package main
    2
    3 import "fmt"
    4
    5 type Complex struct {
    6     Value *int
    7 }
    8
    9 func PointyInt(a int) *int {
   10     return &a
   11 }
   12
   13 func main() {
   14     a := []*Complex{
   15         {
   16             Value: PointyInt(1),
   17         },
   18     }
   19
   20     b := []int{1, 2, 3, 4}
 * 21     fmt.Println("vim-go", a, b)
   22 }

On stepping through the debugger I expect to see the a variable in the Local Variables section:

a: []*main.Complex[824633868568]
b: []int[4]

Up to this point this is the expected outcome, however if I try to expand the a Slice above using the <CR> binding, it doesn't work, while is works perfectly for b.

# Local Variables
a: []*main.Complex[1]
b: []int[4]
 b[0]: int(1)
 b[1]: int(2)
 b[2]: int(3)
 b[3]: int(4)

What did you expect to happen?

I expect even the pointer slices to be expanded in the local variables section

What happened instead?

Cannot expand the variable which is a slice of pointers

Configuration (MUST fill this out):

No custom configuration apart from the vimrc linked below

vim-go version: latest

vimrc you used to reproduce:

vimrc

set nocompatible                " be iMproved, required
filetype plugin indent on       " required

" set syntax highlighting on
syntax on

" set line number on
set number

" turn off line wraping
set nowrap

" enable backspace in vim on mac
set backspace=indent,eol,start

" set options for youcompleteme whitlist files
let g:ycm_filetype_whitelist = {'c': 1, 'cpp': 1, 'python': 1, 'go': 1, 'erlang': 1}

" auto-close ycm preview window after completion
let g:ycm_autoclose_preview_window_after_completion = 1

au BufNewFile,BufRead *.py
    \ set tabstop=4 |
    \ set softtabstop=4 |
    \ set shiftwidth=4 |
    " \ set textwidth=79 |
    \ set expandtab |
    \ set autoindent |
    \ set fileformat=unix |
    \ set formatprg=autopep8\ -|

au BufNewFile,BufRead *.js,*.html,*.css,*.yml,*.yaml,*.tf,*.tfvar
    \ set tabstop=2 |
    \ set softtabstop=2 |
    \ set shiftwidth=2 |
    \ set expandtab |
    \ set autoindent |

au BufNewFile,BufRead *.go
    \ set tabstop=4 |
    \ set softtabstop=4 |
    \ set shiftwidth=4 |
    \ set noexpandtab |
    \ set autoindent |
    \ set smarttab

" go tab settings
"autocmd Filetype *.go set tabstop=4 softtabstop=0 shiftwidth=4 noexpandtab

" allow shortcut for split resizing
nnoremap <c-w>> :vertical resize +10<cr>
nnoremap <c-w>< :vertical resize -10<cr>

" set vim-airline to always appear
set laststatus=2

" vim airline - tabline
let g:airline#extensions#tabline#enabled = 1

" intergate vim-airline with powerline fonts
let g:airline_powerline_fonts = 1

" set the runtime path to include Vundle and initialize
set rtp+=~/.vim/bundle/Vundle.vim
call vundle#begin()
" alternatively, pass a path where Vundle should install plugins
"call vundle#begin('~/some/path/here')

" let Vundle manage Vundle, required
Plugin 'gmarik/Vundle.vim'

" The following are examples of different formats supported.
" Keep Plugin commands between vundle#begin/end.

" Themes
" Plugin 'kristijanhusak/vim-hybrid-material'
" Plugin 'scwood/vim-hybrid'
" Plugin 'vim-airline/vim-airline-themes'
" Plugin 'vim-airline/vim-airline'
" Plugin 'edkolev/tmuxline.vim'

" Plugin 'altercation/vim-colors-solarized'

" typescript highlighting
" Plugin 'clausreinke/typescript-tools.vim'
" Plugin 'leafgarland/typescript-vim'

" Non-themes
" Plugin 'scrooloose/nerdtree'
" Plugin 'Xuyuanp/nerdtree-git-plugin'
" Plugin 'jmcantrell/vim-virtualenv'
" Plugin 'airblade/vim-gitgutter'
" Plugin 'tpope/vim-fugitive'
" Plugin 'Valloric/YouCompleteMe'
" Plugin 'nvie/vim-flake8'
" Plugin 'tell-k/vim-autopep8'

" Plugin 'w0rp/ale'
" Plugin 'luochen1990/rainbow'

" Plugin 'vimwiki/vimwiki'
" Plugin 'kien/ctrlp.vim'

" vim-go
Plugin 'fatih/vim-go'
Plugin 'nsf/gocode', {'rtp': 'vim/'}
Plugin 'sebdah/vim-delve'
" Plugin 'mdempsky/gocode', {'rtp': 'vim/'}

autocmd StdinReadPre * let s:std_in=1
autocmd VimEnter * if argc() == 0 && !exists("s:std_in") | NERDTree | endif

map <C-f> :NERDTreeToggle<CR>

call vundle#end()            " required
filetype plugin indent on    " required

" first set 256 color support
set t_Co=256

" set dark background
set background=dark

" set colorscheme
colorscheme solarized

" If you don't want airline colors in tmuxline
let g:airline#extensions#tmuxline#enabled = 0

" setting default theme for airline
let g:airline_theme='base16_solarized'

" detect ctrl arrow keys inside tmux
if &term =~ '^screen'
    " tmux will send xterm-style keys when its xterm-keys option is on
    execute "set <xUp>=\e[1;*A"
    execute "set <xDown>=\e[1;*B"
    execute "set <xRight>=\e[1;*C"
    execute "set <xLeft>=\e[1;*D"
endif

set encoding=utf-8

" CtrlP binding
let g:ctrlp_map = '<C-l>'

let g:go_metalinter_enabled = ['vet', 'golint']
let g:go_fmt_command = "goimports"
let g:go_autodetect_gopath = 1
let g:go_list_type = "location list"
" let g:go_metalinter_autosave = 1
let g:go_auto_sameids = 1

let g:go_highlight_types = 1
let g:go_highlight_fields = 1
let g:go_highlight_functions = 1
let g:go_highlight_function_calls = 1
let g:go_highlight_extra_types = 1
let g:go_highlight_generate_tags = 1

let g:go_def_mode='gopls'
let g:go_info_mode='gopls'
let g:go_rename_command='gopls'

let g:ctrlp_show_hidden = 1

let g:terraform_align=1

" Tab navigation like Firefox.
nnoremap <C-p> :bprevious<CR>
map <C-p> :bprevious<CR>
imap <C-p> <Esc>:bprevious<CR>
map <C-n>   :bnext<CR>
imap <C-n>    <Esc>:bnext<CR>
nnoremap <C-t>     :enew<CR>
imap <C-t>  <Esc>:enew<CR>
map <C-q>       :bdelete<CR>
imap <C-q>       :bdelete<CR>
nnoremap <C-q>     :bdelete<CR>
inoremap <C-q>     <Esc>:bdelete<CR>

" remap ; to : when in normal mode
" nnoremap ; :

" ycm autocomplete
set omnifunc=youcompleteme#Complete
set completefunc=youcompleteme#Complete

Vim version (first three lines from :version):

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Apr 01 2021 08:32:44)
macOS version - x86_64
Included patches: 1-2681

Go version (go version):

go version go1.16.5 darwin/amd64

Go environment

go env Output:

GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/ishankhare/Library/Caches/go-build"
GOENV="/Users/ishankhare/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="/Users/ishankhare/godev/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="darwin"
GOPATH="/Users/ishankhare/godev"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/Cellar/go/1.16.5/libexec"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.16.5/libexec/pkg/tool/darwin_amd64"
GOVCS=""
GOVERSION="go1.16.5"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD="/Users/ishankhare/ishan/helm/go.mod"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/d_/ts9r3x654zb8x10kxfdfzf_00000gn/T/go-build2088288958=/tmp/go-build -gno-record-gcc-switches -fno-common"

gopls version

gopls version Output:

golang.org/x/tools/gopls v0.7.0
    golang.org/x/tools/gopls@v0.7.0 h1:JQBHW81Gsyim6iDjUwGoPeSpXrSqwen3isPJLfDfaYU=