vim-patch:8.1.0468: MS-Windows: filter command with pipe character fa…

…ils (#9101)

Problem:    MS-Windows: Filter command with pipe character fails. (Johannes
            Riecken)
Solution:   Find the pipe character outside of quotes. (Yasuhiro Matsumoto,
            closes vim/vim#1743, closes vim/vim#3523)
vim/vim@0664089

src/nvim/ex_cmds.c

@@ -1353,6 +1353,25 @@ do_shell(
   apply_autocmds(EVENT_SHELLCMDPOST, NULL, NULL, FALSE, curbuf);
 }
 
+#if !defined(UNIX)
+static char *find_pipe(const char *cmd)
+{
+  bool inquote = false;
+
+  for (const char *p = cmd; *p != NUL; p++) {
+    if (!inquote && *p == '|') {
+      return p;
+    }
+    if (*p == '"') {
+      inquote = !inquote;
+    } else if (rem_backslash((const char_u *)p)) {
+      p++;
+    }
+  }
+  return NULL;
+}
+#endif
+
 /// Create a shell command from a command string, input redirection file and
 /// output redirection file.
 ///
@@ -1406,15 +1425,15 @@ char_u *make_filter_cmd(char_u *cmd, char_u *itmp, char_u *otmp)
     // Don't do this when 'shellquote' is not empty, otherwise the
     // redirection would be inside the quotes.
     if (*p_shq == NUL) {
-      char *const p = strchr(buf, '|');
+      char *const p = find_pipe(buf);
       if (p != NULL) {
         *p = NUL;
       }
     }
     xstrlcat(buf, " < ", len);
     xstrlcat(buf, (const char *)itmp, len);
     if (*p_shq == NUL) {
-      const char *const p = strchr((const char *)cmd, '|');
+      const char *const p = find_pipe((const char *)cmd);
       if (p != NULL) {
         xstrlcat(buf, " ", len - 1);  // Insert a space before the '|' for DOS
         xstrlcat(buf, p, len - 1);

src/nvim/testdir/test_filter_cmd.vim

@@ -74,3 +74,16 @@ func Test_filter_cmd_completion()
   call assert_equal('filter /pat/ print', s:complete_filter_cmd('filter /pat/ pri'))
   call assert_equal('filter #pat# print', s:complete_filter_cmd('filter #pat# pri'))
 endfunc
+
+func Test_filter_cmd_with_filter()
+  new
+  set shelltemp
+  %!echo "a|b"
+  let out = getline(1)
+  bw!
+  if has('win32')
+    let out = trim(out, '" ')
+  endif
+  call assert_equal('a|b', out)
+  set shelltemp&
+endfunction