parse extended glob patterns in command substitutions in compatibility mode, even if extglob is not set

parse.y

@@ -1666,7 +1666,7 @@ rewind_input_string ()
     xchars++;
 
   /* XXX - how to reflect bash_input.location.string back to string passed to
-     parse_and_execute or xparse_dolparen?  xparse_dolparen needs to know how
+     parse_and_execute or xparse_dolparen? xparse_dolparen needs to know how
      far into the string we parsed.  parse_and_execute knows where bash_input.
      location.string is, and how far from orig_string that is -- that's the
      number of characters the command consumed. */
@@ -3303,7 +3303,7 @@ reset_parser ()
 
 #if defined (EXTENDED_GLOB)
   /* Reset to global value of extended glob */
-  if (parser_state & PST_EXTPAT)
+  if (parser_state & (PST_EXTPAT|PST_CMDSUBST))
     extended_glob = global_extglob;
 #endif
 
@@ -3328,6 +3328,11 @@ reset_parser ()
 
   eol_ungetc_lookahead = 0;
 
+  /* added post-bash-5.1 */
+  need_here_doc = 0;
+  redir_stack[0] = 0;
+  esacs_needed_count = expecting_in_token = 0;
+
   current_token = '\n';		/* XXX */
   last_read_token = '\n';
   token_to_read = '\n';
@@ -4098,6 +4103,7 @@ parse_comsub (qc, open, close, lenp, flags)
   saved_global = global_command;		/* might not be necessary */
   global_command = (COMMAND *)NULL;
 
+  /* These are reset by reset_parser() */
   need_here_doc = 0;
   esacs_needed_count = expecting_in_token = 0;
 
@@ -4107,9 +4113,13 @@ parse_comsub (qc, open, close, lenp, flags)
      backwards compatibility. */
   if (expand_aliases)
     expand_aliases = posixly_correct != 0;
+#if defined (EXTENDED_GLOB)
+  global_extglob = extended_glob;
+  if (shell_compatibility_level <= 51)
+    extended_glob = 1;
+#endif
 
   current_token = '\n';				/* XXX */
-
   token_to_read = DOLPAREN;			/* let's trick the parser */
 
   r = yyparse ();
@@ -4120,11 +4130,20 @@ parse_comsub (qc, open, close, lenp, flags)
       gather_here_documents ();	/* XXX check compatibility level? */
     }
 
+#if defined (EXTENDED_GLOB)
+  extended_glob = global_extglob;
+#endif
+
   parsed_command = global_command;
 
   if (EOF_Reached)
-    /* yyparse() has already called yyerror() */
-    return (&matched_pair_error);
+    {
+      shell_eof_token = ps.eof_token;
+      expand_aliases = ps.expand_aliases;
+
+      /* yyparse() has already called yyerror() and reset_parser() */
+      return (&matched_pair_error);
+    }
   else if (r != 0)
     {
       /* parser_error (start_lineno, _("could not parse command substitution")); */
@@ -4135,13 +4154,26 @@ parse_comsub (qc, open, close, lenp, flags)
       if (interactive_shell == 0)
 	jump_to_top_level (FORCE_EOF);	/* This is like reader_loop() */
       else
-	jump_to_top_level (DISCARD);
+	{
+	  shell_eof_token = ps.eof_token;
+	  expand_aliases = ps.expand_aliases;
+
+	  jump_to_top_level (DISCARD);
+	}
     }
 
   if (current_token != shell_eof_token)
     {
 INTERNAL_DEBUG(("current_token (%d) != shell_eof_token (%c)", current_token, shell_eof_token));
       token_to_read = current_token;
+
+      /* If we get here we can check eof_encountered and if it's 1 but the
+	 previous EOF_Reached test didn't succeed, we can assume that the shell
+	 is interactive and ignoreeof is set. We might want to restore the
+	 parser state in this case. */
+      shell_eof_token = ps.eof_token;
+      expand_aliases = ps.expand_aliases;
+
       return (&matched_pair_error);
     }
 
@@ -4226,6 +4258,9 @@ xparse_dolparen (base, string, indp, flags)
      command substitution and we want to defer it completely until then. The
      old value will be restored by restore_parser_state(). */
   expand_aliases = 0;
+#if defined (EXTENDED_GLOB)
+  global_extglob = extended_glob;
+#endif
 
   token_to_read = DOLPAREN;			/* let's trick the parser */
 
@@ -4236,7 +4271,7 @@ xparse_dolparen (base, string, indp, flags)
   if (current_token == shell_eof_token)
     yyclearin;		/* might want to clear lookahead token unconditionally */
 
-  reset_parser ();
+  reset_parser ();	/* resets extended_glob too */
   /* reset_parser() clears shell_input_line and associated variables, including
      parser_state, so we want to reset things, then restore what we need. */
   restore_input_line_state (&ls);