vim-patch:8.2.1384: no ATTENTION prompt for :vimgrep first match file

Problem:    No ATTENTION prompt for :vimgrep first match file.
Solution:   When there is an existing swap file do not keep the dummy buffer.
            (closes vim/vim#6649)
https://github.com/vim/vim/commit/8ce4b7ed85a7c6499bea5eb1312c85ee7a00e364

1 files changed, 17 insertions, 1 deletions

diff --git a/src/nvim/quickfix.c b/src/nvim/quickfix.c
index 5ade59d224..9352d5e8cc 100644
--- a/src/nvim/quickfix.c
+++ b/src/nvim/quickfix.c
@@ -5068,6 +5068,20 @@ static void vgr_jump_to_match(qf_info_T *qi, int forceit, int *redraw_for_dummy,
   }
 }
 
+// Return true if "buf" had an existing swap file, the current swap file does
+// not end in ".swp".
+static bool existing_swapfile(const buf_T *buf)
+  FUNC_ATTR_NONNULL_ALL FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
+{
+  if (buf->b_ml.ml_mfp != NULL) {
+    const char_u *const fname = buf->b_ml.ml_mfp->mf_fname;
+    const size_t len = STRLEN(fname);
+
+    return fname[len - 1] != 'p' || fname[len - 2] != 'w';
+  }
+  return false;
+}
+
 // ":vimgrep {pattern} file(s)"
 // ":vimgrepadd {pattern} file(s)"
 // ":lvimgrep {pattern} file(s)"
@@ -5225,7 +5239,9 @@ void ex_vimgrep(exarg_T *eap)
           if (!found_match) {
             wipe_dummy_buffer(buf, dirname_start);
             buf = NULL;
-          } else if (buf != first_match_buf || (flags & VGR_NOJUMP)) {
+          } else if (buf != first_match_buf
+                     || (flags & VGR_NOJUMP)
+                     || existing_swapfile(buf)) {
             unload_dummy_buffer(buf, dirname_start);
             // Keeping the buffer, remove the dummy flag.
             buf->b_flags &= ~BF_DUMMY;