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d1cc31c5f0
* tests/conflicts.at (%nonassoc and eof): Extend to test that it prevents the omission of expected tokens for %error-verbose.
1072 lines
20 KiB
Plaintext
1072 lines
20 KiB
Plaintext
# Exercising Bison on conflicts. -*- Autotest -*-
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# Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008, 2009 Free Software
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# Foundation, Inc.
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# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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AT_BANNER([[Conflicts.]])
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## ---------------- ##
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## S/R in initial. ##
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## ---------------- ##
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# I once hacked Bison in such a way that it lost its reductions on the
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# initial state (because it was confusing it with the last state). It
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# took me a while to strip down my failures to this simple case. So
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# make sure it finds the s/r conflict below.
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AT_SETUP([S/R in initial])
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AT_DATA([[input.y]],
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[[%expect 1
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%%
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exp: e 'e';
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e: 'e' | /* Nothing. */;
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]])
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AT_BISON_CHECK([-o input.c input.y], 0, [],
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[[input.y:4.9: warning: rule useless in parser due to conflicts: e: /* empty */
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]])
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AT_CLEANUP
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## ------------------- ##
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## %nonassoc and eof. ##
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## ------------------- ##
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AT_SETUP([%nonassoc and eof])
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AT_DATA_GRAMMAR([input.y],
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[[
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%{
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#define YYERROR_VERBOSE 1
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static void
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yyerror (const char *msg)
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{
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fprintf (stderr, "%s\n", msg);
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}
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/* The current argument. */
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static const char *input;
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static int
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yylex (void)
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{
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static size_t toknum;
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if (! (toknum <= strlen (input)))
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abort ();
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return input[toknum++];
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}
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%}
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%nonassoc '<' '>'
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%%
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expr: expr '<' expr
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| expr '>' expr
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| '0'
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;
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%%
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int
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main (int argc, const char *argv[])
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{
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input = argc <= 1 ? "" : argv[1];
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return yyparse ();
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}
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]])
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# Specify the output files to avoid problems on different file systems.
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AT_BISON_CHECK([-o input.c input.y])
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AT_COMPILE([input])
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AT_PARSER_CHECK([./input '0<0'])
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AT_PARSER_CHECK([./input '0<0<0'], [1], [],
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[syntax error, unexpected '<'
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])
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AT_PARSER_CHECK([./input '0>0'])
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AT_PARSER_CHECK([./input '0>0>0'], [1], [],
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[syntax error, unexpected '>'
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])
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AT_PARSER_CHECK([./input '0<0>0'], [1], [],
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[syntax error, unexpected '>'
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])
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# We must disable default reductions in inconsistent states in order to
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# have an explicit list of all expected tokens. (However, unless we use
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# canonical LR, lookahead sets are merged for different left contexts,
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# so it is still possible to have extra incorrect tokens in the expected
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# list. That just doesn't happen to be a problem for this test case.)
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AT_BISON_CHECK([-Dlr.default-reductions=consistent -o input.c input.y])
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AT_COMPILE([input])
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AT_PARSER_CHECK([./input '0<0'])
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AT_PARSER_CHECK([./input '0<0<0'], [1], [],
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[syntax error, unexpected '<', expecting $end
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])
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AT_PARSER_CHECK([./input '0>0'])
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AT_PARSER_CHECK([./input '0>0>0'], [1], [],
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[syntax error, unexpected '>', expecting $end
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])
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AT_PARSER_CHECK([./input '0<0>0'], [1], [],
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[syntax error, unexpected '>', expecting $end
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])
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AT_CLEANUP
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## ------------------------- ##
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## Unresolved SR Conflicts. ##
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## ------------------------- ##
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AT_SETUP([Unresolved SR Conflicts])
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AT_KEYWORDS([report])
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AT_DATA([input.y],
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[[%token NUM OP
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%%
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exp: exp OP exp | NUM;
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]])
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AT_BISON_CHECK([-o input.c --report=all input.y], 0, [],
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[input.y: conflicts: 1 shift/reduce
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])
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# Check the contents of the report.
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AT_CHECK([cat input.output], [],
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[[State 5 conflicts: 1 shift/reduce
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Grammar
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0 $accept: exp $end
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1 exp: exp OP exp
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2 | NUM
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Terminals, with rules where they appear
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$end (0) 0
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error (256)
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NUM (258) 2
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OP (259) 1
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Nonterminals, with rules where they appear
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$accept (5)
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on left: 0
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exp (6)
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on left: 1 2, on right: 0 1
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state 0
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0 $accept: . exp $end
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1 exp: . exp OP exp
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2 | . NUM
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NUM shift, and go to state 1
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exp go to state 2
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state 1
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2 exp: NUM .
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$default reduce using rule 2 (exp)
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state 2
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0 $accept: exp . $end
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1 exp: exp . OP exp
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$end shift, and go to state 3
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OP shift, and go to state 4
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state 3
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0 $accept: exp $end .
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$default accept
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state 4
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1 exp: . exp OP exp
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1 | exp OP . exp
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2 | . NUM
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NUM shift, and go to state 1
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exp go to state 5
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state 5
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1 exp: exp . OP exp
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1 | exp OP exp . [$end, OP]
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OP shift, and go to state 4
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OP [reduce using rule 1 (exp)]
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$default reduce using rule 1 (exp)
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]])
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AT_CLEANUP
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## ----------------------- ##
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## Resolved SR Conflicts. ##
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## ----------------------- ##
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AT_SETUP([Resolved SR Conflicts])
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AT_KEYWORDS([report])
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AT_DATA([input.y],
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[[%token NUM OP
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%left OP
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%%
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exp: exp OP exp | NUM;
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]])
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AT_BISON_CHECK([-o input.c --report=all input.y])
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# Check the contents of the report.
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AT_CHECK([cat input.output], [],
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[[Grammar
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0 $accept: exp $end
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1 exp: exp OP exp
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2 | NUM
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Terminals, with rules where they appear
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$end (0) 0
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error (256)
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NUM (258) 2
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OP (259) 1
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Nonterminals, with rules where they appear
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$accept (5)
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on left: 0
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exp (6)
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on left: 1 2, on right: 0 1
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state 0
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0 $accept: . exp $end
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1 exp: . exp OP exp
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2 | . NUM
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NUM shift, and go to state 1
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exp go to state 2
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state 1
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2 exp: NUM .
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$default reduce using rule 2 (exp)
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state 2
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0 $accept: exp . $end
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1 exp: exp . OP exp
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$end shift, and go to state 3
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OP shift, and go to state 4
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state 3
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0 $accept: exp $end .
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$default accept
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state 4
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1 exp: . exp OP exp
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1 | exp OP . exp
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2 | . NUM
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NUM shift, and go to state 1
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exp go to state 5
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state 5
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1 exp: exp . OP exp
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1 | exp OP exp . [$end, OP]
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$default reduce using rule 1 (exp)
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Conflict between rule 1 and token OP resolved as reduce (%left OP).
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]])
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AT_CLEANUP
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## ---------------------- ##
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## %precedence suffices. ##
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## ---------------------- ##
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AT_SETUP([%precedence suffices])
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AT_DATA([input.y],
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[[%precedence "then"
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%precedence "else"
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%%
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stmt:
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"if" cond "then" stmt
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| "if" cond "then" stmt "else" stmt
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| "stmt"
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;
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cond:
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"exp"
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;
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]])
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AT_BISON_CHECK([-o input.c input.y])
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AT_CLEANUP
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## ------------------------------ ##
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## %precedence does not suffice. ##
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## ------------------------------ ##
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AT_SETUP([%precedence does not suffice])
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AT_DATA([input.y],
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[[%precedence "then"
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%precedence "else"
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%%
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stmt:
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"if" cond "then" stmt
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| "if" cond "then" stmt "else" stmt
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| "stmt"
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;
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cond:
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"exp"
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| cond "then" cond
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;
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]])
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AT_BISON_CHECK([-o input.c input.y], 0, [],
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[[input.y: conflicts: 1 shift/reduce
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input.y:12.3-18: warning: rule useless in parser due to conflicts: cond: cond "then" cond
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]])
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AT_CLEANUP
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## -------------------------------- ##
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## Defaulted Conflicted Reduction. ##
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## -------------------------------- ##
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# When there are RR conflicts, some rules are disabled. Usually it is
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# simply displayed as:
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#
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# $end reduce using rule 3 (num)
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# $end [reduce using rule 4 (id)]
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#
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# But when `reduce 3' is the default action, we'd produce:
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#
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# $end [reduce using rule 4 (id)]
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# $default reduce using rule 3 (num)
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#
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# In this precise case (a reduction is masked by the default
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# reduction), we make the `reduce 3' explicit:
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#
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# $end reduce using rule 3 (num)
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# $end [reduce using rule 4 (id)]
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# $default reduce using rule 3 (num)
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#
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# Maybe that's not the best display, but then, please propose something
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# else.
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AT_SETUP([Defaulted Conflicted Reduction])
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AT_KEYWORDS([report])
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AT_DATA([input.y],
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[[%%
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exp: num | id;
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num: '0';
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id : '0';
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%%
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]])
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AT_BISON_CHECK([-o input.c --report=all input.y], 0, [],
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[[input.y: conflicts: 1 reduce/reduce
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input.y:4.6-8: warning: rule useless in parser due to conflicts: id: '0'
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]])
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# Check the contents of the report.
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AT_CHECK([cat input.output], [],
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[[Rules useless in parser due to conflicts
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4 id: '0'
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State 1 conflicts: 1 reduce/reduce
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Grammar
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0 $accept: exp $end
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1 exp: num
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2 | id
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3 num: '0'
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4 id: '0'
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Terminals, with rules where they appear
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$end (0) 0
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'0' (48) 3 4
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error (256)
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Nonterminals, with rules where they appear
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$accept (4)
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on left: 0
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exp (5)
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on left: 1 2, on right: 0
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num (6)
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on left: 3, on right: 1
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id (7)
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on left: 4, on right: 2
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state 0
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0 $accept: . exp $end
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1 exp: . num
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2 | . id
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3 num: . '0'
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4 id: . '0'
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'0' shift, and go to state 1
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exp go to state 2
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num go to state 3
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id go to state 4
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state 1
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3 num: '0' . [$end]
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4 id: '0' . [$end]
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$end reduce using rule 3 (num)
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$end [reduce using rule 4 (id)]
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$default reduce using rule 3 (num)
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state 2
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0 $accept: exp . $end
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$end shift, and go to state 5
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state 3
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1 exp: num .
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$default reduce using rule 1 (exp)
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state 4
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2 exp: id .
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$default reduce using rule 2 (exp)
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state 5
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0 $accept: exp $end .
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$default accept
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]])
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AT_CLEANUP
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## -------------------- ##
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## %expect not enough. ##
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## -------------------- ##
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AT_SETUP([%expect not enough])
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AT_DATA([input.y],
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[[%token NUM OP
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%expect 0
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%%
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exp: exp OP exp | NUM;
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]])
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AT_BISON_CHECK([-o input.c input.y], 1, [],
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[input.y: conflicts: 1 shift/reduce
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input.y: expected 0 shift/reduce conflicts
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])
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AT_CLEANUP
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## --------------- ##
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## %expect right. ##
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## --------------- ##
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AT_SETUP([%expect right])
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AT_DATA([input.y],
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[[%token NUM OP
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%expect 1
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%%
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exp: exp OP exp | NUM;
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]])
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AT_BISON_CHECK([-o input.c input.y])
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AT_CLEANUP
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## ------------------ ##
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## %expect too much. ##
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## ------------------ ##
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AT_SETUP([%expect too much])
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AT_DATA([input.y],
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[[%token NUM OP
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%expect 2
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%%
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exp: exp OP exp | NUM;
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]])
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AT_BISON_CHECK([-o input.c input.y], 1, [],
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[input.y: conflicts: 1 shift/reduce
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input.y: expected 2 shift/reduce conflicts
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])
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AT_CLEANUP
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## ------------------------------- ##
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## %expect with reduce conflicts. ##
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## ------------------------------- ##
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AT_SETUP([%expect with reduce conflicts])
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AT_DATA([input.y],
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[[%expect 0
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%%
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program: a 'a' | a a;
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a: 'a';
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]])
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AT_BISON_CHECK([-o input.c input.y], 1, [],
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[input.y: conflicts: 1 reduce/reduce
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input.y: expected 0 reduce/reduce conflicts
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])
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AT_CLEANUP
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## ------------------------- ##
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## %prec with user strings. ##
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## ------------------------- ##
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AT_SETUP([%prec with user string])
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AT_DATA([[input.y]],
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[[%%
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exp:
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"foo" %prec "foo"
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;
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]])
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AT_BISON_CHECK([-o input.c input.y])
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AT_CLEANUP
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## -------------------------------- ##
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## %no-default-prec without %prec. ##
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## -------------------------------- ##
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AT_SETUP([%no-default-prec without %prec])
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AT_DATA([[input.y]],
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[[%left '+'
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%left '*'
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%%
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%no-default-prec;
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e: e '+' e
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| e '*' e
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| '0'
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;
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]])
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AT_BISON_CHECK([-o input.c input.y], 0, [],
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[[input.y: conflicts: 4 shift/reduce
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]])
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AT_CLEANUP
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## ----------------------------- ##
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## %no-default-prec with %prec. ##
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## ----------------------------- ##
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AT_SETUP([%no-default-prec with %prec])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%left '+'
|
|
%left '*'
|
|
|
|
%%
|
|
|
|
%no-default-prec;
|
|
|
|
e: e '+' e %prec '+'
|
|
| e '*' e %prec '*'
|
|
| '0'
|
|
;
|
|
]])
|
|
|
|
AT_BISON_CHECK([-o input.c input.y])
|
|
AT_CLEANUP
|
|
|
|
|
|
## --------------- ##
|
|
## %default-prec. ##
|
|
## --------------- ##
|
|
|
|
AT_SETUP([%default-prec])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%left '+'
|
|
%left '*'
|
|
|
|
%%
|
|
|
|
%default-prec;
|
|
|
|
e: e '+' e
|
|
| e '*' e
|
|
| '0'
|
|
;
|
|
]])
|
|
|
|
AT_BISON_CHECK([-o input.c input.y])
|
|
AT_CLEANUP
|
|
|
|
|
|
## ---------------------------------------------- ##
|
|
## Unreachable States After Conflict Resolution. ##
|
|
## ---------------------------------------------- ##
|
|
|
|
AT_SETUP([[Unreachable States After Conflict Resolution]])
|
|
|
|
# If conflict resolution makes states unreachable, remove those states, report
|
|
# rules that are then unused, and don't report conflicts in those states. Test
|
|
# what happens when a nonterminal becomes useless as a result of state removal
|
|
# since that causes lalr.o's goto map to be rewritten.
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%output "input.c"
|
|
%left 'a'
|
|
|
|
%%
|
|
|
|
start: resolved_conflict 'a' reported_conflicts 'a' ;
|
|
|
|
/* S/R conflict resolved as reduce, so the state with item
|
|
* (resolved_conflict: 'a' . unreachable1) and all it transition successors are
|
|
* unreachable, and the associated production is useless. */
|
|
resolved_conflict:
|
|
'a' unreachable1
|
|
| %prec 'a'
|
|
;
|
|
|
|
/* S/R conflict that need not be reported since it is unreachable because of
|
|
* the previous conflict resolution. Nonterminal unreachable1 and all its
|
|
* productions are useless. */
|
|
unreachable1:
|
|
'a' unreachable2
|
|
|
|
|
;
|
|
|
|
/* Likewise for a R/R conflict and nonterminal unreachable2. */
|
|
unreachable2: | ;
|
|
|
|
/* Make sure remaining S/R and R/R conflicts are still reported correctly even
|
|
* when their states are renumbered due to state removal. */
|
|
reported_conflicts:
|
|
'a'
|
|
| 'a'
|
|
|
|
|
;
|
|
|
|
]])
|
|
|
|
AT_BISON_CHECK([[--report=all input.y]], 0, [],
|
|
[[input.y: conflicts: 1 shift/reduce, 1 reduce/reduce
|
|
input.y:12.5-20: warning: rule useless in parser due to conflicts: resolved_conflict: 'a' unreachable1
|
|
input.y:20.5-20: warning: rule useless in parser due to conflicts: unreachable1: 'a' unreachable2
|
|
input.y:21.4: warning: rule useless in parser due to conflicts: unreachable1: /* empty */
|
|
input.y:25.13: warning: rule useless in parser due to conflicts: unreachable2: /* empty */
|
|
input.y:25.16: warning: rule useless in parser due to conflicts: unreachable2: /* empty */
|
|
input.y:31.5-7: warning: rule useless in parser due to conflicts: reported_conflicts: 'a'
|
|
input.y:32.4: warning: rule useless in parser due to conflicts: reported_conflicts: /* empty */
|
|
]])
|
|
|
|
AT_CHECK([[cat input.output]], 0,
|
|
[[Rules useless in parser due to conflicts
|
|
|
|
2 resolved_conflict: 'a' unreachable1
|
|
|
|
4 unreachable1: 'a' unreachable2
|
|
5 | /* empty */
|
|
|
|
6 unreachable2: /* empty */
|
|
7 | /* empty */
|
|
|
|
9 reported_conflicts: 'a'
|
|
10 | /* empty */
|
|
|
|
|
|
State 4 conflicts: 1 shift/reduce
|
|
State 5 conflicts: 1 reduce/reduce
|
|
|
|
|
|
Grammar
|
|
|
|
0 $accept: start $end
|
|
|
|
1 start: resolved_conflict 'a' reported_conflicts 'a'
|
|
|
|
2 resolved_conflict: 'a' unreachable1
|
|
3 | /* empty */
|
|
|
|
4 unreachable1: 'a' unreachable2
|
|
5 | /* empty */
|
|
|
|
6 unreachable2: /* empty */
|
|
7 | /* empty */
|
|
|
|
8 reported_conflicts: 'a'
|
|
9 | 'a'
|
|
10 | /* empty */
|
|
|
|
|
|
Terminals, with rules where they appear
|
|
|
|
$end (0) 0
|
|
'a' (97) 1 2 4 8 9
|
|
error (256)
|
|
|
|
|
|
Nonterminals, with rules where they appear
|
|
|
|
$accept (4)
|
|
on left: 0
|
|
start (5)
|
|
on left: 1, on right: 0
|
|
resolved_conflict (6)
|
|
on left: 2 3, on right: 1
|
|
unreachable1 (7)
|
|
on left: 4 5, on right: 2
|
|
unreachable2 (8)
|
|
on left: 6 7, on right: 4
|
|
reported_conflicts (9)
|
|
on left: 8 9 10, on right: 1
|
|
|
|
|
|
state 0
|
|
|
|
0 $accept: . start $end
|
|
1 start: . resolved_conflict 'a' reported_conflicts 'a'
|
|
2 resolved_conflict: . 'a' unreachable1
|
|
3 | . ['a']
|
|
|
|
$default reduce using rule 3 (resolved_conflict)
|
|
|
|
start go to state 1
|
|
resolved_conflict go to state 2
|
|
|
|
Conflict between rule 3 and token 'a' resolved as reduce (%left 'a').
|
|
|
|
|
|
state 1
|
|
|
|
0 $accept: start . $end
|
|
|
|
$end shift, and go to state 3
|
|
|
|
|
|
state 2
|
|
|
|
1 start: resolved_conflict . 'a' reported_conflicts 'a'
|
|
|
|
'a' shift, and go to state 4
|
|
|
|
|
|
state 3
|
|
|
|
0 $accept: start $end .
|
|
|
|
$default accept
|
|
|
|
|
|
state 4
|
|
|
|
1 start: resolved_conflict 'a' . reported_conflicts 'a'
|
|
8 reported_conflicts: . 'a'
|
|
9 | . 'a'
|
|
10 | . ['a']
|
|
|
|
'a' shift, and go to state 5
|
|
|
|
'a' [reduce using rule 10 (reported_conflicts)]
|
|
|
|
reported_conflicts go to state 6
|
|
|
|
|
|
state 5
|
|
|
|
8 reported_conflicts: 'a' . ['a']
|
|
9 | 'a' . ['a']
|
|
|
|
'a' reduce using rule 8 (reported_conflicts)
|
|
'a' [reduce using rule 9 (reported_conflicts)]
|
|
$default reduce using rule 8 (reported_conflicts)
|
|
|
|
|
|
state 6
|
|
|
|
1 start: resolved_conflict 'a' reported_conflicts . 'a'
|
|
|
|
'a' shift, and go to state 7
|
|
|
|
|
|
state 7
|
|
|
|
1 start: resolved_conflict 'a' reported_conflicts 'a' .
|
|
|
|
$default reduce using rule 1 (start)
|
|
]])
|
|
|
|
AT_DATA([[input-keep.y]],
|
|
[[%define lr.keep-unreachable-states
|
|
]])
|
|
AT_CHECK([[cat input.y >> input-keep.y]])
|
|
|
|
AT_BISON_CHECK([[input-keep.y]], 0, [],
|
|
[[input-keep.y: conflicts: 2 shift/reduce, 2 reduce/reduce
|
|
input-keep.y:22.4: warning: rule useless in parser due to conflicts: unreachable1: /* empty */
|
|
input-keep.y:26.16: warning: rule useless in parser due to conflicts: unreachable2: /* empty */
|
|
input-keep.y:32.5-7: warning: rule useless in parser due to conflicts: reported_conflicts: 'a'
|
|
input-keep.y:33.4: warning: rule useless in parser due to conflicts: reported_conflicts: /* empty */
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
## ------------------------------------------------------------ ##
|
|
## Solved conflicts report for multiple reductions in a state. ##
|
|
## ------------------------------------------------------------ ##
|
|
|
|
AT_SETUP([[Solved conflicts report for multiple reductions in a state]])
|
|
|
|
# Used to lose earlier solved conflict messages even within a single S/R/R.
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%left 'a'
|
|
%right 'b'
|
|
%right 'c'
|
|
%right 'd'
|
|
%%
|
|
start:
|
|
'a'
|
|
| empty_a 'a'
|
|
| 'b'
|
|
| empty_b 'b'
|
|
| 'c'
|
|
| empty_c1 'c'
|
|
| empty_c2 'c'
|
|
| empty_c3 'c'
|
|
;
|
|
empty_a: %prec 'a' ;
|
|
empty_b: %prec 'b' ;
|
|
empty_c1: %prec 'c' ;
|
|
empty_c2: %prec 'c' ;
|
|
empty_c3: %prec 'd' ;
|
|
]])
|
|
AT_BISON_CHECK([[--report=all -o input.c input.y]], 0, [], [ignore])
|
|
AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^state 1$/p']], 0,
|
|
[[state 0
|
|
|
|
0 $accept: . start $end
|
|
1 start: . 'a'
|
|
2 | . empty_a 'a'
|
|
3 | . 'b'
|
|
4 | . empty_b 'b'
|
|
5 | . 'c'
|
|
6 | . empty_c1 'c'
|
|
7 | . empty_c2 'c'
|
|
8 | . empty_c3 'c'
|
|
9 empty_a: . ['a']
|
|
10 empty_b: . []
|
|
11 empty_c1: . []
|
|
12 empty_c2: . []
|
|
13 empty_c3: . ['c']
|
|
|
|
'b' shift, and go to state 1
|
|
|
|
'c' reduce using rule 13 (empty_c3)
|
|
$default reduce using rule 9 (empty_a)
|
|
|
|
start go to state 2
|
|
empty_a go to state 3
|
|
empty_b go to state 4
|
|
empty_c1 go to state 5
|
|
empty_c2 go to state 6
|
|
empty_c3 go to state 7
|
|
|
|
Conflict between rule 9 and token 'a' resolved as reduce (%left 'a').
|
|
Conflict between rule 10 and token 'b' resolved as shift (%right 'b').
|
|
Conflict between rule 11 and token 'c' resolved as shift (%right 'c').
|
|
Conflict between rule 12 and token 'c' resolved as shift (%right 'c').
|
|
Conflict between rule 13 and token 'c' resolved as reduce ('c' < 'd').
|
|
|
|
|
|
state 1
|
|
]])
|
|
|
|
AT_CLEANUP
|
|
|
|
|
|
## ------------------------------------------------------------ ##
|
|
## %nonassoc error actions for multiple reductions in a state. ##
|
|
## ------------------------------------------------------------ ##
|
|
|
|
# Used to abort when trying to resolve conflicts as %nonassoc error actions for
|
|
# multiple reductions in a state.
|
|
|
|
# For a %nonassoc error action token, used to print the first remaining
|
|
# reduction on that token without brackets.
|
|
|
|
AT_SETUP([[%nonassoc error actions for multiple reductions in a state]])
|
|
|
|
AT_DATA([[input.y]],
|
|
[[%nonassoc 'a' 'b' 'c'
|
|
%%
|
|
start:
|
|
'a'
|
|
| empty_a 'a'
|
|
| 'b'
|
|
| empty_b 'b'
|
|
| 'c'
|
|
| empty_c1 'c'
|
|
| empty_c2 'c'
|
|
| empty_c3 'c'
|
|
;
|
|
empty_a: %prec 'a' ;
|
|
empty_b: %prec 'b' ;
|
|
empty_c1: %prec 'c' ;
|
|
empty_c2: %prec 'c' ;
|
|
empty_c3: %prec 'c' ;
|
|
]])
|
|
|
|
AT_BISON_CHECK([[--report=all -o input.c input.y]], 0, [], [ignore])
|
|
AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^state 1$/p']], 0,
|
|
[[state 0
|
|
|
|
0 $accept: . start $end
|
|
1 start: . 'a'
|
|
2 | . empty_a 'a'
|
|
3 | . 'b'
|
|
4 | . empty_b 'b'
|
|
5 | . 'c'
|
|
6 | . empty_c1 'c'
|
|
7 | . empty_c2 'c'
|
|
8 | . empty_c3 'c'
|
|
9 empty_a: . []
|
|
10 empty_b: . []
|
|
11 empty_c1: . []
|
|
12 empty_c2: . ['c']
|
|
13 empty_c3: . ['c']
|
|
|
|
'a' error (nonassociative)
|
|
'b' error (nonassociative)
|
|
'c' error (nonassociative)
|
|
|
|
'c' [reduce using rule 12 (empty_c2)]
|
|
'c' [reduce using rule 13 (empty_c3)]
|
|
|
|
start go to state 1
|
|
empty_a go to state 2
|
|
empty_b go to state 3
|
|
empty_c1 go to state 4
|
|
empty_c2 go to state 5
|
|
empty_c3 go to state 6
|
|
|
|
Conflict between rule 9 and token 'a' resolved as an error (%nonassoc 'a').
|
|
Conflict between rule 10 and token 'b' resolved as an error (%nonassoc 'b').
|
|
Conflict between rule 11 and token 'c' resolved as an error (%nonassoc 'c').
|
|
|
|
|
|
state 1
|
|
]])
|
|
AT_CLEANUP
|