vim-patch:8.1.0213: CTRL-W CR does not work properly in a quickfix window

Problem:    CTRL-W CR does not work properly in a quickfix window.
Solution:   Split the window if needed. (Jason Franklin)
0a08c63da1

src/nvim/normal.c

@@ -5227,12 +5227,8 @@ static void nv_down(cmdarg_T *cap)
     cap->arg = FORWARD;
     nv_page(cap);
   } else if (bt_quickfix(curbuf) && cap->cmdchar == CAR) {
-    // In a quickfix window a <CR> jumps to the error under the cursor.
-    if (curwin->w_llist_ref == NULL) {
-      do_cmdline_cmd(".cc");  // quickfix window
-    } else {
-      do_cmdline_cmd(".ll");  // location list window
-    }
+    // Quickfix window only: view the result under the cursor.
+    qf_view_result(false);
   } else {
     // In the cmdline window a <CR> executes the command.
     if (cmdwin_type != 0 && cap->cmdchar == CAR) {

src/nvim/quickfix.c

@@ -2845,6 +2845,39 @@ static char_u *qf_types(int c, int nr)
   return buf;
 }
 
+// When "split" is false: Open the entry/result under the cursor.
+// When "split" is true: Open the entry/result under the cursor in a new window.
+void qf_view_result(bool split)
+{
+  qf_info_T   *qi = &ql_info;
+
+  if (!bt_quickfix(curbuf)) {
+    return;
+  }
+  if (IS_LL_WINDOW(curwin)) {
+    qi = GET_LOC_LIST(curwin);
+  }
+  if (qi == NULL
+      || qi->qf_lists[qi->qf_curlist].qf_count == 0) {
+    EMSG(_(e_quickfix));
+    return;
+  }
+
+  if (split) {
+    char cmd[32];
+
+    snprintf(cmd, sizeof(cmd), "split +%" PRId64 "%s",
+             (int64_t)curwin->w_cursor.lnum,
+             IS_LL_WINDOW(curwin) ? "ll" : "cc");
+    if (do_cmdline_cmd(cmd) == OK) {
+      do_cmdline_cmd("clearjumps");
+    }
+    return;
+  }
+
+  do_cmdline_cmd((IS_LL_WINDOW(curwin) ? ".ll" : ".cc"));
+}
+
 /*
  * ":cwindow": open the quickfix window if we have errors to display,
  *	       close it if not.

src/nvim/testdir/test_quickfix.vim

@@ -3372,3 +3372,21 @@ func Test_lbuffer_with_bwipe()
     au!
   augroup END
 endfunc
+
+" Tests for the "CTRL-W <CR>" command.
+func Xview_result_split_tests(cchar)
+  call s:setup_commands(a:cchar)
+
+  " Test that "CTRL-W <CR>" in a qf/ll window fails with empty list.
+  call g:Xsetlist([])
+  Xopen
+  let l:win_count = winnr('$')
+  call assert_fails('execute "normal! \<C-W>\<CR>"', 'E42')
+  call assert_equal(l:win_count, winnr('$'))
+  Xclose
+endfunc
+
+func Test_view_result_split()
+  call Xview_result_split_tests('c')
+  call Xview_result_split_tests('l')
+endfunc

src/nvim/window.c

@@ -443,17 +443,11 @@ wingotofile:
     curwin->w_set_curswant = TRUE;
     break;
 
+  // Quickfix window only: view the result under the cursor in a new split.
   case K_KENTER:
   case CAR:
-    /*
-     * In a quickfix window a <CR> jumps to the error under the
-     * cursor in a new window.
-     */
     if (bt_quickfix(curbuf)) {
-      sprintf(cbuf, "split +%" PRId64 "%s",
-              (int64_t)curwin->w_cursor.lnum,
-              (curwin->w_llist_ref == NULL) ? "cc" : "ll");
-      do_cmdline_cmd(cbuf);
+      qf_view_result(true);
     }
     break;