# Exercising Bison Grammar Sets.                      -*- Autotest -*-
# Copyright 2001, 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_EXTRACT_SETS(INPUT, OUTPUT)
# ------------------------------
# Extract the information about the grammar sets from a bison
# trace output (INPUT), and save it in OUTPUT.
# And remember, there is no alternation in portable sed.
m4_define([AT_EXTRACT_SETS],
[AT_DATA([extract.sed],
[[#n
/^NULLABLE$/ {
   :nullable
   p
   n
   /^[ 	]*$/! b nullable
}
/^FIRSTS$/ {
   :firsts
   p
   n
   /^[ 	]*$/! b firsts
}
/^FDERIVES$/ {
   :fderives
   p
   n
   /^[ 	]*$/! b fderives
}
/^DERIVES$/ {
   :derives
   p
   n
   /^[ 	]*$/! b derives
}
]])
AT_CHECK([sed -f extract.sed $1], 0, [stdout])
AT_CHECK([mv stdout $2])
])



AT_BANNER([[Grammar Sets (Firsts etc.).]])


## ---------- ##
## Nullable.  ##
## ---------- ##

AT_SETUP([Nullable])

# At some point, nullable had been smoking grass, and managed to say:
#
# Entering set_nullable
# NULLABLE
#         'e': yes
#         (null): no
# ...

AT_DATA([[input.y]],
[[%%
e: 'e' | /* Nothing */;
]])

AT_CHECK([[bison --trace input.y]], [], [], [stderr])
AT_EXTRACT_SETS([stderr], [sets])
AT_CHECK([[cat sets]], [],
[[DERIVES
	$axiom derives
		1: e $ (rule 0)
	e derives
		2: 'e' (rule 1)
		3: (rule 2)
NULLABLE
	$axiom: no
	e: yes
FIRSTS
	$axiom firsts
		4 ($axiom)
		5 (e)
	e firsts
		5 (e)
FDERIVES
	$axiom derives
		0: e $
		1: 'e'
		2:
	e derives
		1: 'e'
		2:
]])

AT_CLEANUP


## ---------------- ##
## Broken Closure.  ##
## ---------------- ##

# TC was once broken during a massive `simplification' of the code.
# It resulted in bison dumping core on the following grammar (the
# computation of FIRSTS uses TC).  It managed to produce a pretty
# exotic closure:
#
# TC: Input
#
#    01234567
#   +--------+
#  0| 1      |
#  1|  1     |
#  2|   1    |
#  3|    1   |
#  4|     1  |
#  5|      1 |
#  6|       1|
#  7|        |
#   +--------+
#
# TC: Output
#
#    01234567
#   +--------+
#  0| 1      |
#  1| 111    |
#  2| 111    |
#  3| 1111   |
#  4| 111 1  |
#  5| 111  1 |
#  6| 111   1|
#  7| 111    |
#   +--------+
#
# instead of that below.

AT_SETUP([Broken Closure])

AT_DATA([input.y],
[[%%
a: b
b: c
c: d
d: e
e: f
f: g
g: h
h: 'h'
]])

AT_CHECK([[bison --trace input.y]], [], [], [stderr])

AT_CHECK([[sed -n 's/[	 ]*$//;/^TC: Output BEGIN/,/^TC: Output END/p' stderr]], [],
[[TC: Output BEGIN

   012345678
  .---------.
 0| 11111111|
 1|  1111111|
 2|   111111|
 3|    11111|
 4|     1111|
 5|      111|
 6|       11|
 7|        1|
 8|         |
  `---------'
TC: Output END
]])

AT_CLEANUP



## -------- ##
## Firsts.  ##
## -------- ##

AT_SETUP([Firsts])

AT_DATA([input.y],
[[%nonassoc '<' '>'
%left '+' '-'
%right '^' '='
%%
exp:
   exp '<' exp
 | exp '>' exp
 | exp '+' exp
 | exp '-' exp
 | exp '^' exp
 | exp '=' exp
 | "exp"
 ;
]])

AT_CHECK([[bison --trace input.y]], [], [], [stderr])
AT_EXTRACT_SETS([stderr], [sets])
AT_CHECK([[cat sets]], [],
[[DERIVES
	$axiom derives
		1: exp $ (rule 0)
	exp derives
		2: exp '<' exp (rule 1)
		3: exp '>' exp (rule 2)
		4: exp '+' exp (rule 3)
		5: exp '-' exp (rule 4)
		6: exp '^' exp (rule 5)
		7: exp '=' exp (rule 6)
		8: "exp" (rule 7)
NULLABLE
	$axiom: no
	exp: no
FIRSTS
	$axiom firsts
		10 ($axiom)
		11 (exp)
	exp firsts
		11 (exp)
FDERIVES
	$axiom derives
		0: exp $
		1: exp '<' exp
		2: exp '>' exp
		3: exp '+' exp
		4: exp '-' exp
		5: exp '^' exp
		6: exp '=' exp
		7: "exp"
	exp derives
		1: exp '<' exp
		2: exp '>' exp
		3: exp '+' exp
		4: exp '-' exp
		5: exp '^' exp
		6: exp '=' exp
		7: "exp"
]])

AT_CLEANUP