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1# Exercising Bison Grammar Sets.                      -*- Autotest -*-
2# Copyright (C) 2001, 2002, 2005 Free Software Foundation, Inc.
3
4# This program is free software; you can redistribute it and/or modify
5# it under the terms of the GNU General Public License as published by
6# the Free Software Foundation; either version 2, or (at your option)
7# any later version.
8
9# This program is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12# GNU General Public License for more details.
13
14# You should have received a copy of the GNU General Public License
15# along with this program; if not, write to the Free Software
16# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17# 02110-1301, USA.
18
19
20# AT_EXTRACT_SETS(INPUT, OUTPUT)
21# ------------------------------
22# Extract the information about the grammar sets from a bison
23# trace output (INPUT), and save it in OUTPUT.
24# And remember, there is no alternation in portable sed.
25m4_define([AT_EXTRACT_SETS],
26[AT_DATA([extract.sed],
27[[#n
28/^NULLABLE$/ {
29   :null
30   p
31   n
32   /^[	 ]*$/ !b null
33}
34/^FIRSTS$/ {
35   :firsts
36   p
37   n
38   /^[	 ]*$/ !b firsts
39}
40/^FDERIVES$/ {
41   :fderiv
42   p
43   n
44   /^[	 ]*$/ !b fderiv
45}
46/^DERIVES$/ {
47   :deriv
48   p
49   n
50   /^[	 ]*$/ !b deriv
51}
52]])
53AT_CHECK([sed -f extract.sed $1], 0, [stdout])
54AT_CHECK([mv stdout $2])
55])
56
57
58
59AT_BANNER([[Grammar Sets (Firsts etc.).]])
60
61
62## ---------- ##
63## Nullable.  ##
64## ---------- ##
65
66AT_SETUP([Nullable])
67
68# At some point, nullable had been smoking grass, and managed to say:
69#
70# Entering set_nullable
71# NULLABLE
72#         'e': yes
73#         (null): no
74# ...
75
76AT_DATA([[input.y]],
77[[%%
78e: 'e' | /* Nothing */;
79]])
80
81AT_CHECK([[bison --trace=sets input.y]], [], [], [stderr])
82AT_EXTRACT_SETS([stderr], [sets])
83AT_CHECK([[cat sets]], [],
84[[DERIVES
85	$accept derives
86		  0  e $end
87	e derives
88		  1  'e'
89		  2  /* empty */
90NULLABLE
91	$accept: no
92	e: yes
93FIRSTS
94	$accept firsts
95		$accept
96		e
97	e firsts
98		e
99FDERIVES
100	$accept derives
101		  0  e $end
102		  1  'e'
103		  2  /* empty */
104	e derives
105		  1  'e'
106		  2  /* empty */
107]])
108
109AT_CLEANUP
110
111
112## ---------------- ##
113## Broken Closure.  ##
114## ---------------- ##
115
116# TC was once broken during a massive `simplification' of the code.
117# It resulted in bison dumping core on the following grammar (the
118# computation of FIRSTS uses TC).  It managed to produce a pretty
119# exotic closure:
120#
121# TC: Input
122#
123#    01234567
124#   +--------+
125#  0| 1      |
126#  1|  1     |
127#  2|   1    |
128#  3|    1   |
129#  4|     1  |
130#  5|      1 |
131#  6|       1|
132#  7|        |
133#   +--------+
134#
135# TC: Output
136#
137#    01234567
138#   +--------+
139#  0| 1      |
140#  1| 111    |
141#  2| 111    |
142#  3| 1111   |
143#  4| 111 1  |
144#  5| 111  1 |
145#  6| 111   1|
146#  7| 111    |
147#   +--------+
148#
149# instead of that below.
150
151AT_SETUP([Broken Closure])
152
153AT_DATA([input.y],
154[[%%
155a: b;
156b: c;
157c: d;
158d: e;
159e: f;
160f: g;
161g: h;
162h: 'h';
163]])
164
165AT_CHECK([[bison --trace=sets input.y]], [], [], [stderr])
166
167AT_CHECK([[sed -n 's/[	 ]*$//;/^RTC: Firsts Output BEGIN/,/^RTC: Firsts Output END/p' stderr]], [],
168[[RTC: Firsts Output BEGIN
169
170   012345678
171  .---------.
172 0|111111111|
173 1| 11111111|
174 2|  1111111|
175 3|   111111|
176 4|    11111|
177 5|     1111|
178 6|      111|
179 7|       11|
180 8|        1|
181  `---------'
182RTC: Firsts Output END
183]])
184
185AT_CLEANUP
186
187
188
189## -------- ##
190## Firsts.  ##
191## -------- ##
192
193AT_SETUP([Firsts])
194
195AT_DATA([input.y],
196[[%nonassoc '<' '>'
197%left '+' '-'
198%right '^' '='
199%%
200exp:
201   exp '<' exp
202 | exp '>' exp
203 | exp '+' exp
204 | exp '-' exp
205 | exp '^' exp
206 | exp '=' exp
207 | "exp"
208 ;
209]])
210
211AT_CHECK([[bison --trace=sets input.y]], [], [], [stderr])
212AT_EXTRACT_SETS([stderr], [sets])
213AT_CHECK([[cat sets]], [],
214[[DERIVES
215	$accept derives
216		  0  exp $end
217	exp derives
218		  1  exp '<' exp
219		  2  exp '>' exp
220		  3  exp '+' exp
221		  4  exp '-' exp
222		  5  exp '^' exp
223		  6  exp '=' exp
224		  7  "exp"
225NULLABLE
226	$accept: no
227	exp: no
228FIRSTS
229	$accept firsts
230		$accept
231		exp
232	exp firsts
233		exp
234FDERIVES
235	$accept derives
236		  0  exp $end
237		  1  exp '<' exp
238		  2  exp '>' exp
239		  3  exp '+' exp
240		  4  exp '-' exp
241		  5  exp '^' exp
242		  6  exp '=' exp
243		  7  "exp"
244	exp derives
245		  1  exp '<' exp
246		  2  exp '>' exp
247		  3  exp '+' exp
248		  4  exp '-' exp
249		  5  exp '^' exp
250		  6  exp '=' exp
251		  7  "exp"
252]])
253
254AT_CLEANUP
255
256
257
258
259## -------- ##
260## Accept.  ##
261## -------- ##
262
263# In some weird cases Bison could compute an incorrect final state
264# number.  This happens only if the $end token is used in the user
265# grammar, which is a very suspicious accidental feature introduced as
266# a side effect of allowing the user to name $end using `%token END 0
267# "end of file"'.
268
269AT_SETUP([Accept])
270
271AT_DATA([input.y],
272[[%token END 0
273%%
274input:
275  'a'
276| '(' input ')'
277| '(' error END
278;
279]])
280
281AT_CHECK([[bison -v -o input.c input.y]])
282
283# Get the final state in the parser.
284AT_CHECK([[sed -n 's/.*define YYFINAL *\([0-9][0-9]*\)/final state \1/p' input.c]],
285         0, [stdout])
286mv stdout expout
287
288# Get the final state in the report, from the "accept" action..
289AT_CHECK([sed -n '
290           /^state \(.*\)/{
291	     s//final state \1/
292	     x
293	   }
294	   / accept/{
295	     x
296	     p
297	     q
298	   }
299	' input.output],
300	0, [expout])
301
302AT_CLEANUP
303