Add test glr-regr1.at to check for incorrect collapsing of states during

table compression in GLR parser.

tests/Makefile.am

@@ -48,7 +48,7 @@ TESTSUITE_AT = \
 	synclines.at headers.at actions.at conflicts.at \
 	calc.at \
         torture.at existing.at regression.at \
-	cxx-type.at
+	cxx-type.at glr-regr1.at
 
 TESTSUITE = $(srcdir)/testsuite
 

tests/glr-regr1.at

@@ -0,0 +1,101 @@
+# Checking GLR Parsing: Regression Test           -*- Autotest -*-
+# Copyright (C) 2002 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+# 02111-1307, USA.
+
+AT_BANNER([[GLR Regression Test #1.]])
+
+AT_SETUP([Badly Collapsed GLR States])
+
+AT_DATA([glr-regr1.y],
+[[/* Regression Test: Improper state compression */
+/* Reported by Scott McPeak */
+
+%{
+#include <stdio.h>    // fgetc, printf
+
+#define YYSTYPE int
+static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1);
+%}
+
+
+%glr-parser
+
+
+/* -------- productions ------ */
+%%
+
+StartSymbol: E  { $$=0; }                   %merge <exprMerge>
+           ;
+
+E: E 'P' E { $$=1; printf("E -> E 'P' E\n"); }  %merge <exprMerge>
+ | 'B'     { $$=2; printf("E -> 'B'\n"); }      %merge <exprMerge>
+ ;
+
+
+
+/* ---------- C code ----------- */
+%%
+
+static YYSTYPE exprMerge (YYSTYPE x0, YYSTYPE x1)
+{
+  printf ("<OR>\n");
+  return 0;
+}
+
+int main()
+{
+  yyparse();
+  return 0;
+}
+
+int yyerror(char const *msg)
+{
+  printf("%s\n", msg);
+  exit(4);
+}
+
+
+int yylex()
+{
+  while (1) {
+    int ch = fgetc(stdin);
+    if (ch == EOF) {
+      return 0;   // bison's EOF
+    } else if (ch == 'B' || ch == 'P') {
+      return ch;
+    }
+  }
+}
+]])
+
+AT_CHECK([[bison -o glr-regr1.c glr-regr1.y]], 0, [],
+[glr-regr1.y: warning: 1 shift/reduce conflict
+])
+AT_COMPILE([glr-regr1])
+AT_CHECK([[echo BPBPB | ./glr-regr1]], 0, 
+[[E -> 'B'
+E -> 'B'
+E -> E 'P' E
+E -> 'B'
+E -> E 'P' E
+E -> 'B'
+E -> E 'P' E
+E -> E 'P' E
+<OR>
+]], [])
+
+AT_CLEANUP

tests/testsuite.at

@@ -77,5 +77,8 @@ m4_include([existing.at])
 # Some old bugs.
 m4_include([regression.at])
 
-# GLR tests: C++ types, simplified
+# GLR tests: 
+# C++ types, simplified
 m4_include([cxx-type.at])
+# Regression test for state-folding optimization
+m4_include([glr-regr1.at])