X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/da730230ce159265f4380daa456e3e3c5f9422f4..24bb8c8c257631f988941fcd78ecce09bc5d5f23:/tests/conflicts.at diff --git a/tests/conflicts.at b/tests/conflicts.at index 866b9441..705419b9 100644 --- a/tests/conflicts.at +++ b/tests/conflicts.at @@ -1,6 +1,6 @@ # Exercising Bison on conflicts. -*- Autotest -*- -# Copyright (C) 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc. +# 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 @@ -98,26 +98,170 @@ 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 + + + ## ------------------------- ## ## Unresolved SR Conflicts. ## ## ------------------------- ## @@ -326,6 +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. ## ## -------------------------------- ## @@ -523,9 +723,9 @@ input.y: expected 2 shift/reduce conflicts AT_CLEANUP -## ------------------------------ ## -## %expect with reduce conflicts ## -## ------------------------------ ## +## ------------------------------- ## +## %expect with reduce conflicts. ## +## ------------------------------- ## AT_SETUP([%expect with reduce conflicts]) @@ -543,9 +743,26 @@ input.y: expected 0 reduce/reduce conflicts AT_CLEANUP -## ------------------------------- ## -## %no-default-prec without %prec ## -## ------------------------------- ## +## ------------------------- ## +## %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]) @@ -569,9 +786,9 @@ AT_BISON_CHECK([-o input.c input.y], 0, [], AT_CLEANUP -## ---------------------------- ## -## %no-default-prec with %prec ## -## ---------------------------- ## +## ----------------------------- ## +## %no-default-prec with %prec. ## +## ----------------------------- ## AT_SETUP([%no-default-prec with %prec]) @@ -593,9 +810,9 @@ AT_BISON_CHECK([-o input.c input.y]) AT_CLEANUP -## ---------------- ## -## %default-prec ## -## ---------------- ## +## --------------- ## +## %default-prec. ## +## --------------- ## AT_SETUP([%default-prec]) @@ -813,7 +1030,7 @@ state 7 ]]) AT_DATA([[input-keep.y]], -[[%define lr.keep_unreachable_states +[[%define lr.keep-unreachable-states ]]) AT_CHECK([[cat input.y >> input-keep.y]]) @@ -878,7 +1095,7 @@ AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^state 1$/p']], 0, 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)