X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/6876ecd36eacdc5dbcb193d9caea5a56fa8e907b..bb9191dd311e4c6d80f8dd12c6a7ce9254404fbc:/tests/conflicts.at diff --git a/tests/conflicts.at b/tests/conflicts.at index ec9847aa..705419b9 100644 --- a/tests/conflicts.at +++ b/tests/conflicts.at @@ -1,20 +1,19 @@ # Exercising Bison on conflicts. -*- Autotest -*- -# Copyright (C) 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. +# Copyright (C) 2002-2005, 2007-2010 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 3 of the License, 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. +# along with this program. If not, see . AT_BANNER([[Conflicts.]]) @@ -37,8 +36,8 @@ exp: e 'e'; e: 'e' | /* Nothing. */; ]]) -AT_CHECK([bison -o input.c input.y], 0, [], -[[input.y:4.9: warning: rule never reduced because of conflicts: e: /* empty */ +AT_BISON_CHECK([-o input.c input.y], 0, [], +[[input.y:4.9: warning: rule useless in parser due to conflicts: e: /* empty */ ]]) AT_CLEANUP @@ -54,30 +53,26 @@ AT_DATA_GRAMMAR([input.y], [[ %{ #include - -#if STDC_HEADERS -# include -#endif +#include +#include #define YYERROR_VERBOSE 1 static void yyerror (const char *msg) { fprintf (stderr, "%s\n", msg); - exit (1); } /* The current argument. */ -static const char *input = NULL; +static const char *input; static int yylex (void) { - /* No token stands for end of file. */ - if (input && *input) - return *input++; - else - return 0; + static size_t toknum; + if (! (toknum <= strlen (input))) + abort (); + return input[toknum++]; } %} @@ -93,33 +88,176 @@ expr: expr '<' expr int main (int argc, const char *argv[]) { - if (argc > 1) - input = argv[1]; + input = argc <= 1 ? "" : argv[1]; return yyparse (); } ]]) # Specify the output files to avoid problems on different file systems. -AT_CHECK([bison -o input.c input.y]) +AT_BISON_CHECK([-o input.c input.y]) AT_COMPILE([input]) AT_PARSER_CHECK([./input '0<0']) -# FIXME: This is an actual bug, but a new one, in the sense that -# no one has ever spotted it! The messages are *wrong*: there should -# be nothing there, it should be expected eof. AT_PARSER_CHECK([./input '0<0<0'], [1], [], - [syntax error, unexpected '<', expecting '<' or '>' + [syntax error, unexpected '<' ]) AT_PARSER_CHECK([./input '0>0']) AT_PARSER_CHECK([./input '0>0>0'], [1], [], - [syntax error, unexpected '>', expecting '<' or '>' + [syntax error, unexpected '>' ]) AT_PARSER_CHECK([./input '0<0>0'], [1], [], - [syntax error, unexpected '>', expecting '<' or '>' + [syntax error, unexpected '>' +]) + +# We must disable default reductions in inconsistent states in order to +# have an explicit list of all expected tokens. (However, unless we use +# canonical LR, lookahead sets are merged for different left contexts, +# so it is still possible to have extra incorrect tokens in the expected +# list. That just doesn't happen to be a problem for this test case.) + +AT_BISON_CHECK([-Dlr.default-reductions=consistent -o input.c input.y]) +AT_COMPILE([input]) + +AT_PARSER_CHECK([./input '0<0']) +AT_PARSER_CHECK([./input '0<0<0'], [1], [], + [syntax error, unexpected '<', expecting $end +]) + +AT_PARSER_CHECK([./input '0>0']) +AT_PARSER_CHECK([./input '0>0>0'], [1], [], + [syntax error, unexpected '>', expecting $end +]) + +AT_PARSER_CHECK([./input '0<0>0'], [1], [], + [syntax error, unexpected '>', expecting $end +]) + +AT_CLEANUP + + + +## ------------------------------------------- ## +## parse.error=verbose and consistent errors. ## +## ------------------------------------------- ## + +AT_SETUP([[parse.error=verbose and consistent errors]]) + +m4_pushdef([AT_CONSISTENT_ERRORS_CHECK], [ + +AT_BISON_CHECK([$1[ -o input.c input.y]]) +AT_COMPILE([[input]]) + +m4_pushdef([AT_EXPECTING], [m4_if($3, [ab], [[, expecting 'a' or 'b']], + $3, [a], [[, expecting 'a']], + $3, [b], [[, expecting 'b']])]) + +AT_PARSER_CHECK([[./input]], [[1]], [], +[[syntax error, unexpected ]$2[]AT_EXPECTING[ +]]) + +m4_popdef([AT_EXPECTING]) + ]) +AT_DATA_GRAMMAR([input.y], +[[%code { + #include + #include + int yylex (void); + void yyerror (char const *); + #define USE(Var) +} + +%define parse.error verbose + +// The point isn't to test IELR here, but state merging happens to +// complicate the example. +%define lr.type ielr + +%nonassoc 'a' + +// If yylval=0 here, then we know that the 'a' destructor is being +// invoked incorrectly for the 'b' set in the semantic action below. +// All 'a' tokens are returned by yylex, which sets yylval=1. +%destructor { + if (!$$) + fprintf (stderr, "Wrong destructor.\n"); +} 'a' + +%% + +// The lookahead assigned by the semantic action isn't needed before +// either error action is encountered. In a previous version of Bison, +// this was a problem as it meant yychar was not translated into yytoken +// before either error action. The second error action thus invoked a +// destructor that it selected according to the incorrect yytoken. The +// first error action would have reported an incorrect unexpected token +// except that, due to another bug, the unexpected token is not reported +// at all because the error action is the default action in a consistent +// state. That bug still needs to be fixed. +start: error-reduce consistent-error 'a' { USE ($3); } ; + +error-reduce: + 'a' 'a' consistent-reduction consistent-error 'a' + { USE (($1, $2, $5)); } +| 'a' error + { USE ($1); } +; + +consistent-reduction: /*empty*/ { + assert (yychar == YYEMPTY); + yylval = 0; + yychar = 'b'; +} ; + +consistent-error: + 'a' { USE ($1); } +| /*empty*/ %prec 'a' +; + +// Provide another context in which all rules are useful so that this +// test case looks a little more realistic. +start: 'b' consistent-error 'b' ; + +%% + +int +yylex (void) +{ + static char const *input = "aa"; + yylval = 1; + return *input++; +} + +void +yyerror (char const *msg) +{ + fprintf (stderr, "%s\n", msg); +} + +int +main (void) +{ + return yyparse (); +} +]]) + +# See comments in grammar for why this test doesn't succeed. +AT_XFAIL_IF([[:]]) + +AT_CONSISTENT_ERRORS_CHECK([], [['b']], [[none]]) +AT_CONSISTENT_ERRORS_CHECK([[-Dlr.default-reductions=consistent]], + [['b']], [[none]]) + +# Canonical LR doesn't foresee the error for 'a'! +AT_CONSISTENT_ERRORS_CHECK([[-Dlr.default-reductions=accepting]], + [[$end]], [[a]]) +AT_CONSISTENT_ERRORS_CHECK([[-Flr.type=canonical-lr]], [[$end]], [[a]]) + +m4_popdef([AT_CONSISTENT_ERRORS_CHECK]) + AT_CLEANUP @@ -138,13 +276,13 @@ AT_DATA([input.y], exp: exp OP exp | NUM; ]]) -AT_CHECK([bison -o input.c --report=all input.y], 0, [], -[input.y: warning: 1 shift/reduce conflict +AT_BISON_CHECK([-o input.c --report=all input.y], 0, [], +[input.y: conflicts: 1 shift/reduce ]) # Check the contents of the report. AT_CHECK([cat input.output], [], -[[State 5 contains 1 shift/reduce conflict. +[[State 5 conflicts: 1 shift/reduce Grammar @@ -218,7 +356,7 @@ state 4 state 5 - 1 exp: exp . OP exp [$end, OP] + 1 exp: exp . OP exp 1 | exp OP exp . [$end, OP] OP shift, and go to state 4 @@ -246,7 +384,7 @@ AT_DATA([input.y], exp: exp OP exp | NUM; ]]) -AT_CHECK([bison -o input.c --report=all input.y]) +AT_BISON_CHECK([-o input.c --report=all input.y]) # Check the contents of the report. AT_CHECK([cat input.output], [], @@ -321,7 +459,7 @@ state 4 state 5 - 1 exp: exp . OP exp [$end, OP] + 1 exp: exp . OP exp 1 | exp OP exp . [$end, OP] $default reduce using rule 1 (exp) @@ -332,6 +470,62 @@ state 5 AT_CLEANUP +## ---------------------- ## +## %precedence suffices. ## +## ---------------------- ## + +AT_SETUP([%precedence suffices]) + +AT_DATA([input.y], +[[%precedence "then" +%precedence "else" +%% +stmt: + "if" cond "then" stmt +| "if" cond "then" stmt "else" stmt +| "stmt" +; + +cond: + "exp" +; +]]) + +AT_BISON_CHECK([-o input.c input.y]) + +AT_CLEANUP + + +## ------------------------------ ## +## %precedence does not suffice. ## +## ------------------------------ ## + +AT_SETUP([%precedence does not suffice]) + +AT_DATA([input.y], +[[%precedence "then" +%precedence "else" +%% +stmt: + "if" cond "then" stmt +| "if" cond "then" stmt "else" stmt +| "stmt" +; + +cond: + "exp" +| cond "then" cond +; +]]) + +AT_BISON_CHECK([-o input.c input.y], 0, [], +[[input.y: conflicts: 1 shift/reduce +input.y:12.3-18: warning: rule useless in parser due to conflicts: cond: cond "then" cond +]]) + +AT_CLEANUP + + ## -------------------------------- ## ## Defaulted Conflicted Reduction. ## ## -------------------------------- ## @@ -368,19 +562,19 @@ id : '0'; %% ]]) -AT_CHECK([bison -o input.c --report=all input.y], 0, [], -[[input.y: warning: 1 reduce/reduce conflict -input.y:4.6-8: warning: rule never reduced because of conflicts: id: '0' +AT_BISON_CHECK([-o input.c --report=all input.y], 0, [], +[[input.y: conflicts: 1 reduce/reduce +input.y:4.6-8: warning: rule useless in parser due to conflicts: id: '0' ]]) # Check the contents of the report. AT_CHECK([cat input.output], [], -[[Rules never reduced +[[Rules useless in parser due to conflicts 4 id: '0' -State 1 contains 1 reduce/reduce conflict. +State 1 conflicts: 1 reduce/reduce Grammar @@ -485,8 +679,8 @@ AT_DATA([input.y], exp: exp OP exp | NUM; ]]) -AT_CHECK([bison -o input.c input.y], 1, [], -[input.y: warning: 1 shift/reduce conflict +AT_BISON_CHECK([-o input.c input.y], 1, [], +[input.y: conflicts: 1 shift/reduce input.y: expected 0 shift/reduce conflicts ]) AT_CLEANUP @@ -505,7 +699,7 @@ AT_DATA([input.y], exp: exp OP exp | NUM; ]]) -AT_CHECK([bison -o input.c input.y]) +AT_BISON_CHECK([-o input.c input.y]) AT_CLEANUP @@ -522,16 +716,16 @@ AT_DATA([input.y], exp: exp OP exp | NUM; ]]) -AT_CHECK([bison -o input.c input.y], 1, [], -[input.y: warning: 1 shift/reduce conflict +AT_BISON_CHECK([-o input.c input.y], 1, [], +[input.y: conflicts: 1 shift/reduce input.y: expected 2 shift/reduce conflicts ]) AT_CLEANUP -## ------------------------------ ## -## %expect with reduce conflicts ## -## ------------------------------ ## +## ------------------------------- ## +## %expect with reduce conflicts. ## +## ------------------------------- ## AT_SETUP([%expect with reduce conflicts]) @@ -542,8 +736,459 @@ program: a 'a' | a a; a: 'a'; ]]) -AT_CHECK([bison -o input.c input.y], 1, [], -[input.y: warning: 1 reduce/reduce conflict +AT_BISON_CHECK([-o input.c input.y], 1, [], +[input.y: conflicts: 1 reduce/reduce input.y: expected 0 reduce/reduce conflicts ]) AT_CLEANUP + + +## ------------------------- ## +## %prec with user strings. ## +## ------------------------- ## + +AT_SETUP([%prec with user string]) + +AT_DATA([[input.y]], +[[%% +exp: + "foo" %prec "foo" +; +]]) + +AT_BISON_CHECK([-o input.c input.y]) +AT_CLEANUP + + +## -------------------------------- ## +## %no-default-prec without %prec. ## +## -------------------------------- ## + +AT_SETUP([%no-default-prec without %prec]) + +AT_DATA([[input.y]], +[[%left '+' +%left '*' + +%% + +%no-default-prec; + +e: e '+' e + | e '*' e + | '0' + ; +]]) + +AT_BISON_CHECK([-o input.c input.y], 0, [], +[[input.y: conflicts: 4 shift/reduce +]]) +AT_CLEANUP + + +## ----------------------------- ## +## %no-default-prec with %prec. ## +## ----------------------------- ## + +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