tests/sets.at

   1 # Exercising Bison Grammar Sets.                      -*- Autotest -*-
   2 # Copyright (C) 2001, 2002 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
  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.
  25 m4_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 ]])
  53 AT_CHECK([sed -f extract.sed $1], 0, [stdout])
  54 AT_CHECK([mv stdout $2])
  55 ])
  56
  57
  58
  59 AT_BANNER([[Grammar Sets (Firsts etc.).]])
  60
  61
  62 ## ---------- ##
  63 ## Nullable.  ##
  64 ## ---------- ##
  65
  66 AT_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
  76 AT_DATA([[input.y]],
  77 [[%%
  78 e: 'e' | /* Nothing */;
  79 ]])
  80
  81 AT_CHECK([[bison --trace input.y]], [], [], [stderr])
  82 AT_EXTRACT_SETS([stderr], [sets])
  83 AT_CHECK([[cat sets]], [],
  84 [[DERIVES
  85         $axiom derives
  86                 1: e $ (rule 0)
  87         e derives
  88                 2: 'e' (rule 1)
  89                 3: (rule 2)
  90 NULLABLE
  91         $axiom: no
  92         e: yes
  93 FIRSTS
  94         $axiom firsts
  95                 $axiom
  96                 e
  97         e firsts
  98                 e
  99 FDERIVES
 100         $axiom derives
 101                 0: e $
 102                 1: 'e'
 103                 2:
 104         e derives
 105                 1: 'e'
 106                 2:
 107 ]])
 108
 109 AT_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
 151 AT_SETUP([Broken Closure])
 152
 153 AT_DATA([input.y],
 154 [[%%
 155 a: b;
 156 b: c;
 157 c: d;
 158 d: e;
 159 e: f;
 160 f: g;
 161 g: h;
 162 h: 'h';
 163 ]])
 164
 165 AT_CHECK([[bison --trace input.y]], [], [], [stderr])
 166
 167 AT_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   `---------'
 182 RTC: Firsts Output END
 183 ]])
 184
 185 AT_CLEANUP
 186
 187
 188
 189 ## -------- ##
 190 ## Firsts.  ##
 191 ## -------- ##
 192
 193 AT_SETUP([Firsts])
 194
 195 AT_DATA([input.y],
 196 [[%nonassoc '<' '>'
 197 %left '+' '-'
 198 %right '^' '='
 199 %%
 200 exp:
 201    exp '<' exp
 202  | exp '>' exp
 203  | exp '+' exp
 204  | exp '-' exp
 205  | exp '^' exp
 206  | exp '=' exp
 207  | "exp"
 208  ;
 209 ]])
 210
 211 AT_CHECK([[bison --trace input.y]], [], [], [stderr])
 212 AT_EXTRACT_SETS([stderr], [sets])
 213 AT_CHECK([[cat sets]], [],
 214 [[DERIVES
 215         $axiom derives
 216                 1: exp $ (rule 0)
 217         exp derives
 218                 2: exp '<' exp (rule 1)
 219                 3: exp '>' exp (rule 2)
 220                 4: exp '+' exp (rule 3)
 221                 5: exp '-' exp (rule 4)
 222                 6: exp '^' exp (rule 5)
 223                 7: exp '=' exp (rule 6)
 224                 8: "exp" (rule 7)
 225 NULLABLE
 226         $axiom: no
 227         exp: no
 228 FIRSTS
 229         $axiom firsts
 230                 $axiom
 231                 exp
 232         exp firsts
 233                 exp
 234 FDERIVES
 235         $axiom derives
 236                 0: exp $
 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
 254 AT_CLEANUP