vim-patch:7.4.1640

Problem:    Crash when an autocommand changes a quickfix list. (Dominique)
Solution:   Check wether an entry is still valid. (Yegappan Lakshmanan,
            Hirohito Higashi)

ffec3c5349

runtime/doc/quickfix.txt

@@ -53,6 +53,10 @@ command with 'l'.
 If the current window was closed by an |autocommand| while processing a
 location list command, it will be aborted.
 
+							*E925* *E926*
+If the current quickfix or location list was changed by an |autocommand| while
+processing a quickfix or location list command, it will be aborted.
+
 							*:cc*
 :cc[!] [nr]		Display error [nr].  If [nr] is omitted, the same
 			error is displayed again.  Without [!] this doesn't

src/nvim/quickfix.c

@@ -1254,6 +1254,32 @@ static char_u *qf_guess_filepath(char_u *filename)
 
 }
 
+/// When loading a file from the quickfix, the auto commands may modify it.
+/// This may invalidate the current quickfix entry.  This function checks
+/// whether a entry is still present in the quickfix.
+/// Similar to location list.
+static bool is_qf_entry_present(qf_info_T *qi, qfline_T *qf_ptr)
+{
+  qf_list_T *qfl;
+  qfline_T *qfp;
+  int i;
+
+  qfl = &qi->qf_lists[qi->qf_curlist];
+
+  // Search for the entry in the current list
+  for (i = 0, qfp = qfl->qf_start; i < qfl->qf_count; i++, qfp = qfp->qf_next) {
+    if (qfp == qf_ptr) {
+      break;
+    }
+  }
+
+  if (i == qfl->qf_count) {  // Entry is not found
+    return false;
+  }
+
+  return true;
+}
+
 /*
  * jump to a quickfix line
  * if dir == FORWARD go "errornr" valid entries forward
@@ -1585,14 +1611,29 @@ win_found:
                      oldwin == curwin ? curwin : NULL);
       }
     } else {
+      int old_qf_curlist = qi->qf_curlist;
+      bool is_abort = false;
+
       ok = buflist_getfile(qf_ptr->qf_fnum, (linenr_T)1,
                            GETF_SETMARK | GETF_SWITCH, forceit);
       if (qi != &ql_info && !win_valid(oldwin)) {
         EMSG(_("E924: Current window was closed"));
+        is_abort = true;
+        opened_window = false;
+      } else if (old_qf_curlist != qi->qf_curlist
+                 || !is_qf_entry_present(qi, qf_ptr)) {
+        if (qi == &ql_info) {
+          EMSG(_("E925: Current quickfix was changed"));
+        } else {
+          EMSG(_("E926: Current location list was changed"));
+        }
+        is_abort = true;
+      }
+
+      if (is_abort) {
         ok = false;
         qi = NULL;
         qf_ptr = NULL;
-        opened_window = false;
       }
     }
   }

src/nvim/version.c

@@ -804,7 +804,7 @@ static int included_patches[] = {
   1643,
   1642,
   1641,
-  // 1640,
+  1640,
   // 1639,
   // 1638,
   // 1637 NA

test/functional/legacy/quickfix_spec.lua

@@ -265,7 +265,7 @@ describe('helpgrep', function()
             autocmd BufReadCmd t call R(expand("<amatch>"))
           augroup END
 
-          function R(n)
+          function! R(n)
             quit
           endfunc
 
@@ -406,6 +406,43 @@ describe('helpgrep', function()
         augroup END
         augroup! QfBufWinEnter
       endfunc
+
+      function XquickfixChangedByAutocmd(cchar)
+        let Xolder = a:cchar . 'older'
+        let Xgetexpr = a:cchar . 'getexpr'
+        let Xrewind = a:cchar . 'rewind'
+        if a:cchar == 'c'
+          let Xsetlist = 'setqflist('
+          let ErrorNr = 'E925'
+          function! ReadFunc()
+            colder
+            cgetexpr []
+          endfunc
+        else
+          let Xsetlist = 'setloclist(0,'
+          let ErrorNr = 'E926'
+          function! ReadFunc()
+            lolder
+            lgetexpr []
+          endfunc
+        endif
+
+        augroup testgroup
+          au!
+          autocmd BufReadCmd t call ReadFunc()
+        augroup END
+
+        bwipe!
+        let words = [ "a", "b" ]
+        let qflist = []
+        for word in words
+          call add(qflist, {'filename': 't'})
+          exec "call " . Xsetlist . "qflist, '')"
+        endfor
+        exec "call assert_fails('" . Xrewind . "', '" . ErrorNr . ":')"
+
+        augroup! testgroup
+      endfunc
       ]])
   end)
 
@@ -478,6 +515,13 @@ describe('helpgrep', function()
     call('Test_locationlist')
     expected_empty()
   end)
+
+  it('is changed by autocmd', function()
+    call('XquickfixChangedByAutocmd', 'c')
+    expected_empty()
+    call('XquickfixChangedByAutocmd', 'l')
+    expected_empty()
+  end)
 end)
 
 describe('errorformat', function()