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)

src/normal.c

@@ -6202,18 +6202,12 @@ nv_down(cmdarg_T *cap)
 	cap->arg = FORWARD;
 	nv_page(cap);
     }
-    else
 #if defined(FEAT_QUICKFIX)
-    /* In a quickfix window a <CR> jumps to the error under the cursor. */
+    /* Quickfix window only: view the result under the cursor. */
-    if (bt_quickfix(curbuf) && cap->cmdchar == CAR)
+    else if (bt_quickfix(curbuf) && cap->cmdchar == CAR)
-    {
+	qf_view_result(FALSE);
-	if (curwin->w_llist_ref == NULL)
-	    do_cmdline_cmd((char_u *)".cc");	/* quickfix window */
-	else
-	    do_cmdline_cmd((char_u *)".ll");	/* location list window */
-    }
-    else
 #endif
+    else
     {
 #ifdef FEAT_CMDWIN
 	/* In the cmdline window a <CR> executes the command. */

src/proto/quickfix.pro

@@ -7,6 +7,7 @@ void qf_list(exarg_T *eap);
 void qf_age(exarg_T *eap);
 void qf_history(exarg_T *eap);
 void qf_mark_adjust(win_T *wp, linenr_T line1, linenr_T line2, long amount, long amount_after);
+void qf_view_result(int split);
 void ex_cwindow(exarg_T *eap);
 void ex_cclose(exarg_T *eap);
 void ex_copen(exarg_T *eap);

src/quickfix.c

@@ -3489,6 +3489,42 @@ 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(int 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_u      cmd[32];
+
+	vim_snprintf((char *)cmd, sizeof(cmd), "split +%ld%s",
+		(long)curwin->w_cursor.lnum,
+		IS_LL_WINDOW(curwin) ? "ll" : "cc");
+	if (do_cmdline_cmd(cmd) == OK)
+	    do_cmdline_cmd((char_u *) "clearjumps");
+	return;
+    }
+
+    do_cmdline_cmd((char_u *)(IS_LL_WINDOW(curwin) ? ".ll" : ".cc"));
+}
+
 /*
  * ":cwindow": open the quickfix window if we have errors to display,
  *	       close it if not.

src/testdir/test_quickfix.vim

@@ -3504,3 +3504,21 @@ func Test_filter_clist()
   call assert_equal([' 1 abc:pat1:  '],
 			\ split(execute('filter /pat1/ clist'), "\n"))
 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/version.c

@@ -793,6 +793,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    213,
 /**/
     212,
 /**/

src/window.c

@@ -520,23 +520,14 @@ wingotofile:
 		break;
 #endif
 
+/* Quickfix window only: view the result under the cursor in a new split. */
+#if defined(FEAT_QUICKFIX)
     case K_KENTER:
     case CAR:
-#if defined(FEAT_QUICKFIX)
-		/*
-		 * In a quickfix window a <CR> jumps to the error under the
-		 * cursor in a new window.
-		 */
 		if (bt_quickfix(curbuf))
-		{
+		    qf_view_result(TRUE);
-		    sprintf((char *)cbuf, "split +%ld%s",
-				(long)curwin->w_cursor.lnum,
-				(curwin->w_llist_ref == NULL) ? "cc" : "ll");
-		    do_cmdline_cmd(cbuf);
-		}
-#endif
 		break;
-
+#endif
 
 /* CTRL-W g  extended commands */
     case 'g':