fix(api): nvim_cmd handle 0 range (#19655)

Fixes #19608

src/nvim/ex_docmd.c

@@ -1693,6 +1693,8 @@ int execute_cmd(exarg_T *eap, CmdParseInfo *cmdinfo, bool preview)
     ERROR(_(e_cannot_edit_other_buf));
   }
 
+  correct_range(eap);
+
   if (((eap->argt & EX_WHOLEFOLD) || eap->addr_count >= 2) && !global_busy
       && eap->addr_type == ADDR_LINES) {
     // Put the first line at the start of a closed fold, put the last line

test/functional/api/vim_spec.lua

@@ -3822,5 +3822,12 @@ describe('API', function()
       feed("[l")
       neq(nil, string.find(eval("v:errmsg"), "E5108:"))
     end)
+    it('handles 0 range #19608', function()
+      meths.buf_set_lines(0, 0, -1, false, { "aa" })
+      meths.cmd({ cmd = 'delete', range = { 0 } }, {})
+      command('undo')
+      eq({'aa'}, meths.buf_get_lines(0, 0, 1, false))
+      assert_alive()
+    end)
   end)
 end)