vim-patch:8.1.0392: error while typing :/foo/s// with 'incsearch' enabled

Problem:    Error while typing :/foo/s// with 'incsearch' enabled.
Solution:   Do not give search errors when highlighting matches.
https://github.com/vim/vim/commit/50eb16c3b23235b21ce4494673a7741a9a196176

3 files changed, 22 insertions, 14 deletions

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index 78d46ad5ee..dfebd13868 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -1371,7 +1371,7 @@ static char_u * do_one_cmd(char_u **cmdlinep,
   }
 
   ea.cmd = cmd;
-  if (parse_cmd_address(&ea, &errormsg) == FAIL) {
+  if (parse_cmd_address(&ea, &errormsg, false) == FAIL) {
     goto doend;
   }
 
@@ -2229,7 +2229,7 @@ int parse_command_modifiers(exarg_T *eap, char_u **errormsg, bool skip_only)
 
     case 't':   if (checkforcmd(&p, "tab", 3)) {
       long tabnr = get_address(
-          eap, &eap->cmd, ADDR_TABS, eap->skip, false, 1);
+          eap, &eap->cmd, ADDR_TABS, eap->skip, skip_only, false, 1);
 
       if (tabnr == MAXLNUM) {
         cmdmod.tab = tabpage_index(curtab) + 1;
@@ -2301,9 +2301,9 @@ static void free_cmdmod(void)
 
 
 // Parse the address range, if any, in "eap".
-// May set the last search pattern.
+// May set the last search pattern, unless "silent" is true.
 // Return FAIL and set "errormsg" or return OK.
-int parse_cmd_address(exarg_T *eap, char_u **errormsg)
+int parse_cmd_address(exarg_T *eap, char_u **errormsg, bool silent)
   FUNC_ATTR_NONNULL_ALL
 {
   int address_count = 1;
@@ -2341,7 +2341,7 @@ int parse_cmd_address(exarg_T *eap, char_u **errormsg)
         break;
     }
     eap->cmd = skipwhite(eap->cmd);
-    lnum = get_address(eap, &eap->cmd, eap->addr_type, eap->skip,
+    lnum = get_address(eap, &eap->cmd, eap->addr_type, eap->skip, silent,
                        eap->addr_count == 0, address_count++);
     if (eap->cmd == NULL) {  // error detected
       return FAIL;
@@ -3695,6 +3695,7 @@ static linenr_T get_address(exarg_T *eap,
                             char_u **ptr,
                             int addr_type,  // flag: one of ADDR_LINES, ...
                             int skip,  // only skip the address, don't use it
+                            bool silent,  // no errors or side effects
                             int to_other_file,  // flag: may jump to other file
                             int address_count)  // 1 for first, >1 after comma
 {
@@ -3826,13 +3827,15 @@ static linenr_T get_address(exarg_T *eap,
         if (*cmd == c)
           ++cmd;
       } else {
-        pos = curwin->w_cursor;                     /* save curwin->w_cursor */
-        /*
-         * When '/' or '?' follows another address, start
-         * from there.
-         */
-        if (lnum != MAXLNUM)
+        int flags;
+
+        pos = curwin->w_cursor;  // save curwin->w_cursor
+
+        // When '/' or '?' follows another address, start from
+        // there.
+        if (lnum != MAXLNUM) {
           curwin->w_cursor.lnum = lnum;
+        }
 
         // Start a forward search at the end of the line (unless
         // before the first line).
@@ -3846,7 +3849,8 @@ static linenr_T get_address(exarg_T *eap,
           curwin->w_cursor.col = 0;
         }
         searchcmdlen = 0;
-        if (!do_search(NULL, c, cmd, 1L, SEARCH_HIS | SEARCH_MSG, NULL)) {
+        flags = silent ? 0 : SEARCH_HIS | SEARCH_MSG;
+        if (!do_search(NULL, c, cmd, 1L, flags, NULL)) {
           curwin->w_cursor = pos;
           cmd = NULL;
           goto error;
@@ -7751,7 +7755,7 @@ static void ex_put(exarg_T *eap)
  */
 static void ex_copymove(exarg_T *eap)
 {
-  long n = get_address(eap, &eap->arg, eap->addr_type, false, false, 1);
+  long n = get_address(eap, &eap->arg, eap->addr_type, false, false, false, 1);
   if (eap->arg == NULL) {  // error detected
     eap->nextcmd = NULL;
     return;
diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index 7cfee9df82..960b7cf03f 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -391,7 +391,7 @@ static bool do_incsearch_highlighting(int firstc, incsearch_state_T *s,
   // parse the address range
   save_cursor = curwin->w_cursor;
   curwin->w_cursor = s->search_start;
-  parse_cmd_address(&ea, &dummy);
+  parse_cmd_address(&ea, &dummy, true);
   if (ea.addr_count > 0) {
     // Allow for reverse match.
     if (ea.line2 < ea.line1) {
diff --git a/src/nvim/testdir/test_search.vim b/src/nvim/testdir/test_search.vim
index 8741def3bf..ec4c15cd11 100644
--- a/src/nvim/testdir/test_search.vim
+++ b/src/nvim/testdir/test_search.vim
@@ -796,6 +796,10 @@ func Test_keep_last_search_pattern()
   call feedkeys(":/foo/s//\<Esc>", 'ntx')
   call assert_equal('bar', @/)
 
+  " no error message if pattern not found
+  call feedkeys(":/xyz/s//\<Esc>", 'ntx')
+  call assert_equal('bar', @/)
+
   bwipe!
   call test_override("ALL", 0)
   set noincsearch