Fugitive.vim allows me to run git grep commands; unfortunately, the results are not stored in a quickfix-list, so I need to run :cw after a :
This works for me:
:command -nargs=+ Ggr execute 'silent Ggrep!' <q-args> | cw | redraw!
Already mentioned in one of the comments, but I thought the plugin-recommended solution on the fugitive.vim site deserved its own answer:
autocmd QuickFixCmdPost *grep* cwindow
(from: https://github.com/tpope/vim-fugitive)
You can use the <args> symbol to insert the arguments given to your custom command:
:command -nargs=+ Ggr execute 'Ggrep' <q-args> | cw
Note: As the :Ggrep command doesn't have the -bar argument, it cannot be chained, so :execute has to be used.