tests/sets.at

   1 # Exercising Bison Grammar Sets.                      -*- Autotest -*-
   2 # Copyright 2001 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., 59 Temple Place - Suite 330, Boston, MA
  17 # 02111-1307, USA.
  18
  19 AT_BANNER([[Grammar Sets (Firsts etc.).]])
  20
  21
  22 ## ---------- ##
  23 ## Nullable.  ##
  24 ## ---------- ##
  25
  26 AT_SETUP([Nullable])
  27
  28 # At some point, nullable had been smoking grass, and managed to say:
  29 #
  30 # Entering set_nullable
  31 # NULLABLE
  32 #         'e': yes
  33 #         (null): no
  34 # ...
  35
  36 AT_DATA([[input.y]],
  37 [[%%
  38 e: 'e' | /* Nothing */;
  39 ]])
  40
  41 AT_CHECK([[bison --trace input.y]], [], [], [stderr])
  42
  43 AT_CHECK([[sed 's/[      ]*$//' stderr]], [],
  44 [[RITEM
  45   e  $  (rule 0)
  46   'e'  (rule 1)
  47   (rule 2)
  48
  49
  50 DERIVES
  51         $axiom derives
  52                 1: e $ (rule 0)
  53         e derives
  54                 2: 'e' (rule 1)
  55                 3: (rule 2)
  56
  57
  58 Entering set_nullable
  59 NULLABLE
  60         $axiom: no
  61         e: yes
  62
  63
  64 TC: Input BEGIN
  65
  66    01
  67   .--.
  68  0| 1|
  69  1|  |
  70   `--'
  71 TC: Input END
  72
  73 TC: Output BEGIN
  74
  75    01
  76   .--.
  77  0| 1|
  78  1|  |
  79   `--'
  80 TC: Output END
  81
  82 FIRSTS
  83         $axiom firsts
  84                 4 ($axiom)
  85                 5 (e)
  86         e firsts
  87                 5 (e)
  88
  89
  90 FDERIVES
  91         $axiom derives
  92                 0: e $
  93                 1: 'e'
  94                 2:
  95         e derives
  96                 1: 'e'
  97                 2:
  98
  99
 100 Processing state 0 (reached by $)
 101 Closure: input
 102
 103
 104 Closure: output
 105    0: . e $  (rule 0)
 106    3: . 'e'  (rule 1)
 107    5: .  (rule 2)
 108
 109
 110 Entering new_itemsets, state = 0
 111 Entering append_states, state = 0
 112 Entering get_state, state = 0, symbol = 3 ('e')
 113 Entering new_state, state = 0, symbol = 3 ('e')
 114 Exiting get_state => 1
 115 Entering get_state, state = 0, symbol = 5 (e)
 116 Entering new_state, state = 0, symbol = 5 (e)
 117 Exiting get_state => 2
 118 Processing state 1 (reached by 'e')
 119 Closure: input
 120    4: .  (rule 1)
 121
 122
 123 Closure: output
 124    4: .  (rule 1)
 125
 126
 127 Entering new_itemsets, state = 1
 128 Entering append_states, state = 1
 129 Processing state 2 (reached by e)
 130 Closure: input
 131    1: . $  (rule 0)
 132
 133
 134 Closure: output
 135    1: . $  (rule 0)
 136
 137
 138 Entering new_itemsets, state = 2
 139 Entering append_states, state = 2
 140 Entering get_state, state = 2, symbol = 0 ($)
 141 Entering new_state, state = 2, symbol = 0 ($)
 142 Exiting get_state => 3
 143 Processing state 3 (reached by $)
 144 Closure: input
 145    2: .  (rule 0)
 146
 147
 148 Closure: output
 149    2: .  (rule 0)
 150
 151
 152 Entering new_itemsets, state = 3
 153 Entering append_states, state = 3
 154 transpose: input
 155   0:
 156
 157 transpose: output
 158   0:
 159
 160 Lookaheads: BEGIN
 161 State 0: 1 lookaheads
 162    on 0 ($) -> rule -4
 163    on 1 (error) -> rule -4
 164    on 2 ($undefined.) -> rule -4
 165    on 3 ('e') -> rule -4
 166 State 1: 0 lookaheads
 167 State 2: 0 lookaheads
 168 State 3: 0 lookaheads
 169 Lookaheads: END
 170 ]])
 171
 172 AT_CLEANUP
 173
 174
 175 ## ---------------- ##
 176 ## Broken Closure.  ##
 177 ## ---------------- ##
 178
 179 # TC was once broken during a massive `simplification' of the code.
 180 # It resulted in bison dumping core on the following grammar (the
 181 # computation of FIRSTS uses TC).  It managed to produce a pretty
 182 # exotic closure:
 183 #
 184 # TC: Input
 185 #
 186 #    01234567
 187 #   +--------+
 188 #  0| 1      |
 189 #  1|  1     |
 190 #  2|   1    |
 191 #  3|    1   |
 192 #  4|     1  |
 193 #  5|      1 |
 194 #  6|       1|
 195 #  7|        |
 196 #   +--------+
 197 #
 198 # TC: Output
 199 #
 200 #    01234567
 201 #   +--------+
 202 #  0| 1      |
 203 #  1| 111    |
 204 #  2| 111    |
 205 #  3| 1111   |
 206 #  4| 111 1  |
 207 #  5| 111  1 |
 208 #  6| 111   1|
 209 #  7| 111    |
 210 #   +--------+
 211 #
 212 # instead of that below.
 213
 214 AT_SETUP([Broken Closure])
 215
 216 AT_DATA([input.y],
 217 [[%%
 218 a: b
 219 b: c
 220 c: d
 221 d: e
 222 e: f
 223 f: g
 224 g: h
 225 h: 'h'
 226 ]])
 227
 228 AT_CHECK([[bison --trace input.y]], [], [], [stderr])
 229
 230 AT_CHECK([[sed -n 's/[   ]*$//;/^TC: Output BEGIN/,/^TC: Output END/p' stderr]], [],
 231 [[TC: Output BEGIN
 232
 233    012345678
 234   .---------.
 235  0| 11111111|
 236  1|  1111111|
 237  2|   111111|
 238  3|    11111|
 239  4|     1111|
 240  5|      111|
 241  6|       11|
 242  7|        1|
 243  8|         |
 244   `---------'
 245 TC: Output END
 246 ]])
 247
 248 AT_CLEANUP