vim-patch:8.1.1015: quickfix buffer shows up in list, can't get buffer number

Problem:    Quickfix buffer shows up in list, can't get buffer number.
Solution:   Make the quickfix buffer unlisted when the quickfix window is
            closed.  get the quickfix buffer number with getqflist().
            (Yegappan Lakshmanan, closes vim/vim#4113)
https://github.com/vim/vim/commit/647e24ba3dbf7ff448aa471b1a659a18267ae056

3 files changed, 39 insertions, 9 deletions

diff --git a/src/nvim/quickfix.c b/src/nvim/quickfix.c
index 06fed9c2cf..713cace259 100644
--- a/src/nvim/quickfix.c
+++ b/src/nvim/quickfix.c
@@ -5577,7 +5577,8 @@ enum {
   QF_GETLIST_SIZE = 0x80,
   QF_GETLIST_TICK = 0x100,
   QF_GETLIST_FILEWINID = 0x200,
-  QF_GETLIST_ALL = 0x3FF,
+  QF_GETLIST_QFBUFNR = 0x400,
+  QF_GETLIST_ALL = 0x7FF,
 };
 
 /// Parse text from 'di' and return the quickfix list items.
@@ -5632,6 +5633,15 @@ static int qf_winid(qf_info_T *qi)
   return 0;
 }
 
+// Returns the number of the buffer displayed in the quickfix/location list
+// window. If there is no buffer associated with the list, then returns 0.
+static int qf_getprop_qfbufnr(const qf_info_T *qi, dict_T *retdict)
+  FUNC_ATTR_NONNULL_ARG(2)
+{
+  return tv_dict_add_nr(retdict, S_LEN("qfbufnr"),
+                        (qi == NULL) ? 0 : qi->qf_bufnr);
+}
+
 /// Convert the keys in 'what' to quickfix list property flags.
 static int qf_getprop_keys2flags(const dict_T *what, bool loclist)
   FUNC_ATTR_NONNULL_ALL FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
@@ -5675,6 +5685,9 @@ static int qf_getprop_keys2flags(const dict_T *what, bool loclist)
   if (loclist && tv_dict_find(what, S_LEN("filewinid")) != NULL) {
     flags |= QF_GETLIST_FILEWINID;
   }
+  if (tv_dict_find(what, S_LEN("qfbufnr")) != NULL) {
+    flags |= QF_GETLIST_QFBUFNR;
+  }
 
   return flags;
 }
@@ -5766,6 +5779,9 @@ static int qf_getprop_defaults(qf_info_T *qi,
   if ((status == OK) && locstack && (flags & QF_GETLIST_FILEWINID)) {
     status = tv_dict_add_nr(retdict, S_LEN("filewinid"), 0);
   }
+  if ((status == OK) && (flags & QF_GETLIST_QFBUFNR)) {
+    status = qf_getprop_qfbufnr(qi, retdict);
+  }
 
   return status;
 }
@@ -5900,6 +5916,9 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
   if ((status == OK) && (wp != NULL) && (flags & QF_GETLIST_FILEWINID)) {
     status = qf_getprop_filewinid(wp, qi, retdict);
   }
+  if ((status == OK) && (flags & QF_GETLIST_QFBUFNR)) {
+    status = qf_getprop_qfbufnr(qi, retdict);
+  }
 
   return status;
 }
diff --git a/src/nvim/testdir/test_quickfix.vim b/src/nvim/testdir/test_quickfix.vim
index dc1b20ce65..a8dd383e8c 100644
--- a/src/nvim/testdir/test_quickfix.vim
+++ b/src/nvim/testdir/test_quickfix.vim
@@ -3217,19 +3217,21 @@ func Xgetlist_empty_tests(cchar)
   call assert_equal(0, g:Xgetlist({'changedtick' : 0}).changedtick)
   if a:cchar == 'c'
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0,
-		  \ 'items' : [], 'nr' : 0, 'size' : 0,
+		  \ 'items' : [], 'nr' : 0, 'size' : 0, 'qfbufnr' : 0,
 		  \ 'title' : '', 'winid' : 0, 'changedtick': 0},
 		  \ g:Xgetlist({'all' : 0}))
   else
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0,
 		\ 'items' : [], 'nr' : 0, 'size' : 0, 'title' : '',
-		\ 'winid' : 0, 'changedtick': 0, 'filewinid' : 0},
+		\ 'winid' : 0, 'changedtick': 0, 'filewinid' : 0,
+		\ 'qfbufnr' : 0},
 		\ g:Xgetlist({'all' : 0}))
   endif
 
   " Quickfix window with empty stack
   silent! Xopen
   let qfwinid = (a:cchar == 'c') ? win_getid() : 0
+  let qfbufnr = (a:cchar == 'c') ? bufnr('') : 0
   call assert_equal(qfwinid, g:Xgetlist({'winid' : 0}).winid)
   Xclose
 
@@ -3261,11 +3263,12 @@ func Xgetlist_empty_tests(cchar)
   if a:cchar == 'c'
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [],
 		\ 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0,
+		\ 'qfbufnr' : qfbufnr,
 		\ 'changedtick' : 0}, g:Xgetlist({'id' : qfid, 'all' : 0}))
   else
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [],
 		\ 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0,
-		\ 'changedtick' : 0, 'filewinid' : 0},
+		\ 'changedtick' : 0, 'filewinid' : 0, 'qfbufnr' : 0},
 		\ g:Xgetlist({'id' : qfid, 'all' : 0}))
   endif
 
@@ -3282,11 +3285,12 @@ func Xgetlist_empty_tests(cchar)
   if a:cchar == 'c'
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [],
 		\ 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0,
-		\ 'changedtick' : 0}, g:Xgetlist({'nr' : 5, 'all' : 0}))
+		\ 'changedtick' : 0, 'qfbufnr' : qfbufnr},
+		\ g:Xgetlist({'nr' : 5, 'all' : 0}))
   else
     call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [],
 		\ 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0,
-		\ 'changedtick' : 0, 'filewinid' : 0},
+		\ 'changedtick' : 0, 'filewinid' : 0, 'qfbufnr' : 0},
 		\ g:Xgetlist({'nr' : 5, 'all' : 0}))
   endif
 endfunc
@@ -4040,6 +4044,7 @@ func Xqfbuf_test(cchar)
   Xclose
   " Even after the quickfix window is closed, the buffer should be loaded
   call assert_true(bufloaded(qfbnum))
+  call assert_true(qfbnum, g:Xgetlist({'qfbufnr' : 0}).qfbufnr)
   Xopen
   " Buffer should be reused when opening the window again
   call assert_equal(qfbnum, bufnr(''))
@@ -4058,7 +4063,7 @@ func Xqfbuf_test(cchar)
     close
     " When the location list window is closed, the buffer name should not
     " change to 'Quickfix List'
-    call assert_match(qfbnum . '  h-  "\[Location List]"', execute('ls'))
+    call assert_match(qfbnum . 'u h-  "\[Location List]"', execute('ls!'))
     call assert_true(bufloaded(qfbnum))
 
     " After deleting a location list buffer using ":bdelete", opening the
@@ -4075,6 +4080,7 @@ func Xqfbuf_test(cchar)
     " removed
     call setloclist(0, [], 'f')
     call assert_false(bufexists(qfbnum))
+    call assert_equal(0, getloclist(0, {'qfbufnr' : 0}).qfbufnr)
 
     " When the location list is freed with the location list window open, the
     " location list buffer should not be lost. It should be reused when the
diff --git a/src/nvim/window.c b/src/nvim/window.c
index e53570edd8..7d08336c25 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -2578,9 +2578,14 @@ int win_close(win_T *win, bool free_buf)
     return OK;
   }
 
-  /* Free independent synblock before the buffer is freed. */
-  if (win->w_buffer != NULL)
+  // Free independent synblock before the buffer is freed.
+  if (win->w_buffer != NULL) {
     reset_synblock(win);
+  }
+  // When the quickfix/location list window is closed, unlist the buffer.
+  if (win->w_buffer != NULL && bt_quickfix(win->w_buffer)) {
+    win->w_buffer->b_p_bl = false;
+  }
 
   /*
    * Close the link to the buffer.