# Exercising Bison on conflicts. -*- Autotest -*-
-# Copyright (C) 2002, 2003, 2004, 2005, 2007, 2009, 2010 Free
-# Software Foundation, Inc.
+# Copyright (C) 2002-2005, 2007-2013 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
AT_BANNER([[Conflicts.]])
+## ------------------------- ##
+## Token declaration order. ##
+## ------------------------- ##
+
+# This test checks that token are declared left to right when in a precedence
+# statement.
+
+AT_SETUP([Token declaration order])
+
+AT_BISON_OPTION_PUSHDEFS
+
+AT_DATA_GRAMMAR([[input.y]],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+}
+%token A B C
+%token D
+%right E F G
+%right H I
+%right J
+%left K
+%left L M N
+%nonassoc O P Q
+%precedence R S T U
+%precedence V W
+%%
+exp: A
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE[
+int main (void)
+{
+ assert (A < B);
+ assert (B < C);
+ assert (C < D);
+ assert (D < E);
+ assert (E < F);
+ assert (F < G);
+ assert (G < H);
+ assert (H < I);
+ assert (I < J);
+ assert (J < K);
+ assert (K < L);
+ assert (L < M);
+ assert (M < N);
+ assert (N < O);
+ assert (O < P);
+ assert (P < Q);
+ assert (Q < R);
+ assert (R < S);
+ assert (S < T);
+ assert (T < U);
+ assert (U < V);
+ assert (V < W);
+ return 0;
+}
+]])
+
+AT_BISON_CHECK([-o input.c input.y])
+AT_COMPILE([input])
+
+AT_PARSER_CHECK([./input])
+
+AT_BISON_OPTION_POPDEFS
+
+AT_CLEANUP
+
+
+## --------------------------------------------------- ##
+## Token declaration order: literals vs. identifiers. ##
+## --------------------------------------------------- ##
+
+# This test checks that when several tokens are declared by the same keyword,
+# some of them defined as a character ('a'), others as simple textual reference
+# (A), they are declared correctly left to right.
+# Previously, the following test would declare the states in the order 'o' 'p'
+# M N, instead of M N 'o' 'p'.
+
+AT_SETUP([Token declaration order: literals vs. identifiers])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[%token 'a' 'b' C D
+%token E F 'g' 'h'
+%right 'i' 'j' K L
+%right M N 'o' 'p'
+%%
+exp: 'a'
+ | 'b'
+ | C
+ | D
+ | E
+ | F
+ | 'g'
+ | 'h'
+ | 'i'
+ | 'j'
+ | K
+ | L
+ | M
+ | N
+ | 'o'
+ | 'p'
+;
+%%
+]])
+
+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: . exp $end
+ 1 exp: . 'a'
+ 2 | . 'b'
+ 3 | . C
+ 4 | . D
+ 5 | . E
+ 6 | . F
+ 7 | . 'g'
+ 8 | . 'h'
+ 9 | . 'i'
+ 10 | . 'j'
+ 11 | . K
+ 12 | . L
+ 13 | . M
+ 14 | . N
+ 15 | . 'o'
+ 16 | . 'p'
+
+ 'a' shift, and go to state 1
+ 'b' shift, and go to state 2
+ C shift, and go to state 3
+ D shift, and go to state 4
+ E shift, and go to state 5
+ F shift, and go to state 6
+ 'g' shift, and go to state 7
+ 'h' shift, and go to state 8
+ 'i' shift, and go to state 9
+ 'j' shift, and go to state 10
+ K shift, and go to state 11
+ L shift, and go to state 12
+ M shift, and go to state 13
+ N shift, and go to state 14
+ 'o' shift, and go to state 15
+ 'p' shift, and go to state 16
+
+ exp go to state 17
+
+
+State 1
+]])
+
+AT_CLEANUP
+
+
+## ------------------------------- ##
+## Useless associativity warning. ##
+## ------------------------------- ##
+
+AT_SETUP([Useless associativity warning])
+
+AT_DATA([[input.y]],
+[[%token EQ "=" PL "+" ST "*" LP "("
+%nonassoc "="
+%left "+"
+%left "*"
+%precedence "("
+%%
+stmt:
+ exp
+| "var" "=" exp
+;
+
+exp:
+ exp "+" exp
+| exp "*" "num"
+| "(" exp ")"
+| "num"
+;
+]])
+
+AT_BISON_CHECK([-Wprecedence input.y], 0, [],
+[[input.y:2.1-9: warning: useless precedence and associativity for "=" [-Wprecedence]
+input.y:4.1-5: warning: useless associativity for "*", use %precedence [-Wprecedence]
+input.y:5.1-11: warning: useless precedence for "(" [-Wprecedence]
+]])
+
+AT_CLEANUP
+
+
+## ---------------------------- ##
+## Useless precedence warning. ##
+## ---------------------------- ##
+
+AT_SETUP([Useless precedence warning])
+
+AT_DATA([[input.y]],
+[[%token A B U V W X Y Z
+%precedence Z
+%left X
+%precedence Y
+%left W
+%right V
+%nonassoc U
+%%
+a: b
+ | a U b
+ | f
+;
+b: c
+ | b V c
+;
+c: d
+ | c W d
+;
+d: A
+ | d X d
+ | d Y A
+;
+f: B
+ | f Z B
+;
+]])
+
+AT_BISON_CHECK([-Wprecedence -fcaret -o input.c input.y], 0, [],
+[[input.y:7.1-9: warning: useless precedence and associativity for U [-Wprecedence]
+ %nonassoc U
+ ^^^^^^^^^
+input.y:6.1-6: warning: useless precedence and associativity for V [-Wprecedence]
+ %right V
+ ^^^^^^
+input.y:5.1-5: warning: useless precedence and associativity for W [-Wprecedence]
+ %left W
+ ^^^^^
+input.y:2.1-11: warning: useless precedence for Z [-Wprecedence]
+ %precedence Z
+ ^^^^^^^^^^^
+]])
+
+AT_CLEANUP
+
## ---------------- ##
## S/R in initial. ##
]])
AT_BISON_CHECK([-o input.c input.y], 0, [],
-[[input.y:4.9: warning: rule useless in parser due to conflicts: e: /* empty */
+[[input.y:4.9: warning: rule useless in parser due to conflicts [-Wother]
+]])
+
+AT_BISON_CHECK([-fcaret -o input.c input.y], 0, [],
+[[input.y:4.9: warning: rule useless in parser due to conflicts [-Wother]
+ e: 'e' | /* Nothing. */;
+ ^
]])
AT_CLEANUP
AT_SETUP([%nonassoc and eof])
+AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([input.y],
[[
%{
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <assert.h>
#define YYERROR_VERBOSE 1
-static void
-yyerror (const char *msg)
-{
- fprintf (stderr, "%s\n", msg);
-}
-
+]AT_YYERROR_DEFINE[
/* The current argument. */
static const char *input;
yylex (void)
{
static size_t toknum;
- if (! (toknum <= strlen (input)))
- abort ();
+ assert (toknum <= strlen (input));
return input[toknum++];
}
return yyparse ();
}
]])
+AT_BISON_OPTION_POPDEFS
-# Specify the output files to avoid problems on different file systems.
-AT_BISON_CHECK([-o input.c input.y])
+m4_pushdef([AT_NONASSOC_AND_EOF_CHECK],
+[AT_BISON_CHECK([$1[ -o input.c input.y]])
AT_COMPILE([input])
+m4_pushdef([AT_EXPECTING], [m4_if($2, [correct], [[, expecting $end]])])
+
AT_PARSER_CHECK([./input '0<0'])
AT_PARSER_CHECK([./input '0<0<0'], [1], [],
- [syntax error, unexpected '<'
+ [syntax error, unexpected '<'AT_EXPECTING
])
AT_PARSER_CHECK([./input '0>0'])
AT_PARSER_CHECK([./input '0>0>0'], [1], [],
- [syntax error, unexpected '>'
+ [syntax error, unexpected '>'AT_EXPECTING
])
AT_PARSER_CHECK([./input '0<0>0'], [1], [],
- [syntax error, unexpected '>'
+ [syntax error, unexpected '>'AT_EXPECTING
])
+m4_popdef([AT_EXPECTING])])
+
+# Expected token list is missing.
+AT_NONASSOC_AND_EOF_CHECK([], [[incorrect]])
+
# 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.)
+# have an explicit list of all expected tokens.
+AT_NONASSOC_AND_EOF_CHECK([[-Dlr.default-reduction=consistent]],
+ [[correct]])
+
+# lr.default-reduction=consistent happens to work for this test case.
+# However, for other grammars, lookahead sets can be merged for
+# different left contexts, so it is still possible to have an incorrect
+# expected list. Canonical LR is almost a general solution (that is, it
+# can fail only when %nonassoc is used), so make sure it gives the same
+# result as above.
+AT_NONASSOC_AND_EOF_CHECK([[-Dlr.type=canonical-lr]], [[correct]])
+
+# parse.lac=full is a completely general solution that does not require
+# any of the above sacrifices. Of course, it does not extend the
+# language-recognition power of LALR to (IE)LR, but it does ensure that
+# the reported list of expected tokens matches what the given parser
+# would have accepted in place of the unexpected token.
+AT_NONASSOC_AND_EOF_CHECK([[-Dparse.lac=full]], [[correct]])
+
+m4_popdef([AT_NONASSOC_AND_EOF_CHECK])
-AT_BISON_CHECK([-Dlr.default-reductions=consistent -o input.c input.y])
-AT_COMPILE([input])
+AT_CLEANUP
-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
-])
+## ------------------------------------------- ##
+## parse.error=verbose and consistent errors. ##
+## ------------------------------------------- ##
-AT_CLEANUP
+AT_SETUP([[parse.error=verbose and consistent errors]])
+m4_pushdef([AT_CONSISTENT_ERRORS_CHECK], [
+AT_BISON_OPTION_PUSHDEFS([$1])
-## -------------------------------------- ##
-## %error-verbose and consistent errors. ##
-## -------------------------------------- ##
+m4_pushdef([AT_YYLEX_PROTOTYPE],
+[AT_SKEL_CC_IF([[int yylex (yy::parser::semantic_type *lvalp)]],
+ [[int yylex (YYSTYPE *lvalp)]])])
-AT_SETUP([[%error-verbose and consistent errors]])
+AT_SKEL_JAVA_IF([AT_DATA], [AT_DATA_GRAMMAR])([input.y],
+[AT_SKEL_JAVA_IF([[
-m4_pushdef([AT_CONSISTENT_ERRORS_CHECK], [
+%code imports {
+ import java.io.IOException;
+}]], [[
-AT_DATA_GRAMMAR([input.y],
-[[%code {
+%code {]AT_SKEL_CC_IF([[
+ #include <string>]], [[
#include <assert.h>
#include <stdio.h>
- int yylex (void);
- void yyerror (char const *);
+ ]AT_YYERROR_DECLARE])[
+ ]AT_YYLEX_PROTOTYPE[;
#define USE(Var)
}
+]AT_SKEL_CC_IF([[%defines]], [[%define api.pure]])])[
+
]$1[
-%error-verbose
+%define parse.error verbose
%%
]$2[
-%%
+]AT_SKEL_JAVA_IF([[%code lexer {]], [[%%]])[
-int
-yylex (void)
-{
- static char const *input = "]$3[";
- yylval = 1;
- return *input++;
-}
+/*--------.
+| yylex. |
+`--------*/]AT_SKEL_JAVA_IF([[
-void
-yyerror (char const *msg)
+public String input = "]$3[";
+public int index = 0;
+public int yylex ()
{
- fprintf (stderr, "%s\n", msg);
+ if (index < input.length ())
+ return input.charAt (index++);
+ else
+ return 0;
}
+public Object getLVal ()
+{
+ return new Integer(1);
+}]], [[
-int
-main (void)
+]AT_YYLEX_PROTOTYPE[
{
- return yyparse ();
-}
-]])
-AT_BISON_CHECK([[-o input.c input.y]])
-AT_COMPILE([[input]])
+ static char const *input = "]$3[";
+ *lvalp = 1;
+ return *input++;
+}]])[
+]AT_YYERROR_DEFINE[
+]AT_SKEL_JAVA_IF([[
+};
+
+%%]])[
+
+/*-------.
+| main. |
+`-------*/
+]AT_MAIN_DEFINE
+])
+
+AT_FULL_COMPILE([[input]])
m4_pushdef([AT_EXPECTING], [m4_if($5, [ab], [[, expecting 'a' or 'b']],
$5, [a], [[, expecting 'a']],
$5, [b], [[, expecting 'b']])])
-AT_PARSER_CHECK([[./input]], [[1]], [[]],
+AT_SKEL_JAVA_IF([AT_JAVA_PARSER_CHECK([[input]], [[0]]],
+ [AT_PARSER_CHECK([[./input]], [[1]]]),
+[[]],
[[syntax error, unexpected ]$4[]AT_EXPECTING[
]])
m4_popdef([AT_EXPECTING])
+m4_popdef([AT_YYLEX_PROTOTYPE])
+AT_BISON_OPTION_POPDEFS
])
+m4_pushdef([AT_PREVIOUS_STATE_GRAMMAR],
+[[%nonassoc 'a';
+
+start: consistent-error-on-a-a 'a' ;
+
+consistent-error-on-a-a:
+ 'a' default-reduction
+ | 'a' default-reduction 'a'
+ | 'a' shift
+ ;
+
+default-reduction: /*empty*/ ;
+shift: 'b' ;
+
+// Provide another context in which all rules are useful so that this
+// test case looks a little more realistic.
+start: 'b' consistent-error-on-a-a 'c' ;
+]])
+
+m4_pushdef([AT_PREVIOUS_STATE_INPUT], [[a]])
+
+# Unfortunately, no expected tokens are reported even though 'b' can be
+# accepted. Nevertheless, the main point of this test is to make sure
+# that at least the unexpected token is reported. In a previous version
+# of Bison, it wasn't reported because the error is detected in a
+# consistent state with an error action, and that case always triggered
+# the simple "syntax error" message.
+#
+# The point isn't to test IELR here, but state merging happens to
+# complicate this example.
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[none]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %glr-parser]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[none]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %language "c++"]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[none]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %language "java"]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[end of input]], [[none]])
+
+# Even canonical LR doesn't foresee the error for 'a'!
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %define lr.default-reduction consistent]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[ab]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %define lr.default-reduction accepting]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[ab]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type canonical-lr]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[ab]])
+
+# Only LAC gets it right.
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type canonical-lr
+ %define parse.lac full]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[b]])
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.type ielr
+ %define parse.lac full]],
+ [AT_PREVIOUS_STATE_GRAMMAR],
+ [AT_PREVIOUS_STATE_INPUT],
+ [[$end]], [[b]])
+
+m4_popdef([AT_PREVIOUS_STATE_GRAMMAR])
+m4_popdef([AT_PREVIOUS_STATE_INPUT])
+
m4_pushdef([AT_USER_ACTION_GRAMMAR],
[[%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.
+// If $$ = 0 here, then we know that the 'a' destructor is being invoked
+// incorrectly for the 'b' set in the semantic action below. All 'a'
+// tokens are returned by yylex, which sets $$ = 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
+// Rather than depend on an inconsistent state to induce reading a
+// lookahead as in the previous grammar, just assign the lookahead in a
+// semantic action. That lookahead 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.
+// except that, due to the bug described in the previous grammar, the
+// unexpected token was not reported at all.
start: error-reduce consistent-error 'a' { USE ($][3); } ;
error-reduce:
]])
m4_pushdef([AT_USER_ACTION_INPUT], [[aa]])
-# See comments in grammar for why this test doesn't succeed.
-AT_XFAIL_IF([[:]])
-
AT_CONSISTENT_ERRORS_CHECK([[]],
[AT_USER_ACTION_GRAMMAR],
[AT_USER_ACTION_INPUT],
[['b']], [[none]])
-AT_CONSISTENT_ERRORS_CHECK([[%define lr.default-reductions consistent]],
+AT_CONSISTENT_ERRORS_CHECK([[%glr-parser]],
+ [AT_USER_ACTION_GRAMMAR],
+ [AT_USER_ACTION_INPUT],
+ [['b']], [[none]])
+# No C++ or Java test because yychar cannot be manipulated by users.
+
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.default-reduction consistent]],
[AT_USER_ACTION_GRAMMAR],
[AT_USER_ACTION_INPUT],
[['b']], [[none]])
# Canonical LR doesn't foresee the error for 'a'!
-AT_CONSISTENT_ERRORS_CHECK([[%define lr.default-reductions accepting]],
+AT_CONSISTENT_ERRORS_CHECK([[%define lr.default-reduction accepting]],
[AT_USER_ACTION_GRAMMAR],
[AT_USER_ACTION_INPUT],
[[$end]], [[a]])
[AT_USER_ACTION_INPUT],
[[$end]], [[a]])
+AT_CONSISTENT_ERRORS_CHECK([[%define parse.lac full]],
+ [AT_USER_ACTION_GRAMMAR],
+ [AT_USER_ACTION_INPUT],
+ [['b']], [[none]])
+AT_CONSISTENT_ERRORS_CHECK([[%define parse.lac full
+ %define lr.default-reduction accepting]],
+ [AT_USER_ACTION_GRAMMAR],
+ [AT_USER_ACTION_INPUT],
+ [[$end]], [[none]])
+
m4_popdef([AT_USER_ACTION_GRAMMAR])
m4_popdef([AT_USER_ACTION_INPUT])
+## ------------------------------------------------------- ##
+## LAC: %nonassoc requires splitting canonical LR states. ##
+## ------------------------------------------------------- ##
+
+# This test case demonstrates that, when %nonassoc is used, canonical
+# LR(1) parser table construction followed by conflict resolution
+# without further state splitting is not always sufficient to produce a
+# parser that can detect all syntax errors as soon as possible on one
+# token of lookahead. However, LAC solves the problem completely even
+# with minimal LR parser tables.
+
+AT_SETUP([[LAC: %nonassoc requires splitting canonical LR states]])
+AT_BISON_OPTION_PUSHDEFS
+AT_DATA_GRAMMAR([[input.y]],
+[[%code {
+ #include <stdio.h>
+ ]AT_YYERROR_DECLARE[
+ ]AT_YYLEX_DECLARE[
+}
+
+%error-verbose
+%nonassoc 'a'
+
+%%
+
+start:
+ 'a' problem 'a' // First context.
+| 'b' problem 'b' // Second context.
+| 'c' reduce-nonassoc // Just makes reduce-nonassoc useful.
+;
+
+problem:
+ look reduce-nonassoc
+| look 'a'
+| look 'b'
+;
+
+// For the state reached after shifting the 'a' in these productions,
+// lookahead sets are the same in both the first and second contexts.
+// Thus, canonical LR reuses the same state for both contexts. However,
+// the lookahead 'a' for the reduction "look: 'a'" later becomes an
+// error action only in the first context. In order to immediately
+// detect the syntax error on 'a' here for only the first context, this
+// canonical LR state would have to be split into two states, and the
+// 'a' lookahead would have to be removed from only one of the states.
+look:
+ 'a' // Reduction lookahead set is always ['a', 'b'].
+| 'a' 'b'
+| 'a' 'c' // 'c' is forgotten as an expected token.
+;
+
+reduce-nonassoc: %prec 'a';
+
+%%
+]AT_YYERROR_DEFINE[
+]AT_YYLEX_DEFINE(["aaa"])[
+]AT_MAIN_DEFINE
+])
+AT_BISON_OPTION_POPDEFS
+
+# Show canonical LR's failure.
+AT_BISON_CHECK([[-Dlr.type=canonical-lr -o input.c input.y]],
+ [[0]], [[]],
+[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[1]], [[]],
+[[syntax error, unexpected 'a', expecting 'b'
+]])
+
+# It's corrected by LAC.
+AT_BISON_CHECK([[-Dlr.type=canonical-lr -Dparse.lac=full \
+ -o input.c input.y]], [[0]], [[]],
+[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[1]], [[]],
+[[syntax error, unexpected 'a', expecting 'b' or 'c'
+]])
+
+# IELR is sufficient when LAC is used.
+AT_BISON_CHECK([[-Dlr.type=ielr -Dparse.lac=full -o input.c input.y]],
+ [[0]], [[]],
+[[input.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+]])
+AT_COMPILE([[input]])
+AT_PARSER_CHECK([[./input]], [[1]], [[]],
+[[syntax error, unexpected 'a', expecting 'b' or 'c'
+]])
+
+AT_CLEANUP
+
## ------------------------- ##
## Unresolved SR Conflicts. ##
## ------------------------- ##
]])
AT_BISON_CHECK([-o input.c --report=all input.y], 0, [],
-[input.y: conflicts: 1 shift/reduce
-])
+[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+]])
# Check the contents of the report.
AT_CHECK([cat input.output], [],
on left: 1 2, on right: 0 1
-state 0
+State 0
0 $accept: . exp $end
1 exp: . exp OP exp
exp go to state 2
-state 1
+State 1
2 exp: NUM .
$default reduce using rule 2 (exp)
-state 2
+State 2
0 $accept: exp . $end
1 exp: exp . OP exp
OP shift, and go to state 4
-state 3
+State 3
0 $accept: exp $end .
$default accept
-state 4
+State 4
1 exp: . exp OP exp
1 | exp OP . exp
exp go to state 5
-state 5
+State 5
1 exp: exp . OP exp
1 | exp OP exp . [$end, OP]
on left: 1 2, on right: 0 1
-state 0
+State 0
0 $accept: . exp $end
1 exp: . exp OP exp
exp go to state 2
-state 1
+State 1
2 exp: NUM .
$default reduce using rule 2 (exp)
-state 2
+State 2
0 $accept: exp . $end
1 exp: exp . OP exp
OP shift, and go to state 4
-state 3
+State 3
0 $accept: exp $end .
$default accept
-state 4
+State 4
1 exp: . exp OP exp
1 | exp OP . exp
exp go to state 5
-state 5
+State 5
1 exp: exp . OP exp
1 | exp OP exp . [$end, OP]
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: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+input.y:12.3-18: warning: rule useless in parser due to conflicts [-Wother]
+]])
+
+AT_CLEANUP
+
+
## -------------------------------- ##
## Defaulted Conflicted Reduction. ##
## -------------------------------- ##
# $end reduce using rule 3 (num)
# $end [reduce using rule 4 (id)]
#
-# But when `reduce 3' is the default action, we'd produce:
+# But when 'reduce 3' is the default action, we'd produce:
#
# $end [reduce using rule 4 (id)]
# $default reduce using rule 3 (num)
#
# In this precise case (a reduction is masked by the default
-# reduction), we make the `reduce 3' explicit:
+# reduction), we make the 'reduce 3' explicit:
#
# $end reduce using rule 3 (num)
# $end [reduce using rule 4 (id)]
]])
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'
+[[input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+input.y:4.6-8: warning: rule useless in parser due to conflicts [-Wother]
]])
# Check the contents of the report.
on left: 4, on right: 2
-state 0
+State 0
0 $accept: . exp $end
1 exp: . num
id go to state 4
-state 1
+State 1
3 num: '0' . [$end]
4 id: '0' . [$end]
$default reduce using rule 3 (num)
-state 2
+State 2
0 $accept: exp . $end
$end shift, and go to state 5
-state 3
+State 3
1 exp: num .
$default reduce using rule 1 (exp)
-state 4
+State 4
2 exp: id .
$default reduce using rule 2 (exp)
-state 5
+State 5
0 $accept: exp $end .
]])
AT_BISON_CHECK([-o input.c input.y], 1, [],
-[input.y: conflicts: 1 shift/reduce
-input.y: expected 0 shift/reduce conflicts
-])
+[[input.y: error: shift/reduce conflicts: 1 found, 0 expected
+]])
AT_CLEANUP
]])
AT_BISON_CHECK([-o input.c input.y], 1, [],
-[input.y: conflicts: 1 shift/reduce
-input.y: expected 2 shift/reduce conflicts
-])
+[[input.y: error: shift/reduce conflicts: 1 found, 2 expected
+]])
AT_CLEANUP
]])
AT_BISON_CHECK([-o input.c input.y], 1, [],
-[input.y: conflicts: 1 reduce/reduce
-input.y: expected 0 reduce/reduce conflicts
-])
+[[input.y: error: reduce/reduce conflicts: 1 found, 0 expected
+]])
AT_CLEANUP
;
]])
-AT_BISON_CHECK([-o input.c input.y], 0, [],
-[[input.y: conflicts: 4 shift/reduce
+AT_BISON_CHECK([-Wall -o input.c input.y], 0, [],
+[[input.y: warning: 4 shift/reduce conflicts [-Wconflicts-sr]
+input.y:1.1-5: warning: useless precedence and associativity for '+' [-Wprecedence]
+input.y:2.1-5: warning: useless precedence and associativity for '*' [-Wprecedence]
]])
AT_CLEANUP
]])
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 */
+[[input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+input.y:12.5-20: warning: rule useless in parser due to conflicts [-Wother]
+input.y:20.5-20: warning: rule useless in parser due to conflicts [-Wother]
+input.y:21.4: warning: rule useless in parser due to conflicts [-Wother]
+input.y:25.13: warning: rule useless in parser due to conflicts [-Wother]
+input.y:25.16: warning: rule useless in parser due to conflicts [-Wother]
+input.y:31.5-7: warning: rule useless in parser due to conflicts [-Wother]
+input.y:32.4: warning: rule useless in parser due to conflicts [-Wother]
]])
AT_CHECK([[cat input.output]], 0,
2 resolved_conflict: 'a' unreachable1
4 unreachable1: 'a' unreachable2
- 5 | /* empty */
+ 5 | %empty
- 6 unreachable2: /* empty */
- 7 | /* empty */
+ 6 unreachable2: %empty
+ 7 | %empty
9 reported_conflicts: 'a'
- 10 | /* empty */
+ 10 | %empty
State 4 conflicts: 1 shift/reduce
1 start: resolved_conflict 'a' reported_conflicts 'a'
2 resolved_conflict: 'a' unreachable1
- 3 | /* empty */
+ 3 | %empty
4 unreachable1: 'a' unreachable2
- 5 | /* empty */
+ 5 | %empty
- 6 unreachable2: /* empty */
- 7 | /* empty */
+ 6 unreachable2: %empty
+ 7 | %empty
8 reported_conflicts: 'a'
9 | 'a'
- 10 | /* empty */
+ 10 | %empty
Terminals, with rules where they appear
on left: 8 9 10, on right: 1
-state 0
+State 0
0 $accept: . start $end
1 start: . resolved_conflict 'a' reported_conflicts 'a'
Conflict between rule 3 and token 'a' resolved as reduce (%left 'a').
-state 1
+State 1
0 $accept: start . $end
$end shift, and go to state 3
-state 2
+State 2
1 start: resolved_conflict . 'a' reported_conflicts 'a'
'a' shift, and go to state 4
-state 3
+State 3
0 $accept: start $end .
$default accept
-state 4
+State 4
1 start: resolved_conflict 'a' . reported_conflicts 'a'
8 reported_conflicts: . 'a'
reported_conflicts go to state 6
-state 5
+State 5
8 reported_conflicts: 'a' . ['a']
9 | 'a' . ['a']
$default reduce using rule 8 (reported_conflicts)
-state 6
+State 6
1 start: resolved_conflict 'a' reported_conflicts . 'a'
'a' shift, and go to state 7
-state 7
+State 7
1 start: resolved_conflict 'a' reported_conflicts 'a' .
]])
AT_DATA([[input-keep.y]],
-[[%define lr.keep-unreachable-states
+[[%define lr.keep-unreachable-state
]])
AT_CHECK([[cat input.y >> input-keep.y]])
AT_BISON_CHECK([[input-keep.y]], 0, [],
-[[input-keep.y: conflicts: 2 shift/reduce, 2 reduce/reduce
-input-keep.y:22.4: warning: rule useless in parser due to conflicts: unreachable1: /* empty */
-input-keep.y:26.16: warning: rule useless in parser due to conflicts: unreachable2: /* empty */
-input-keep.y:32.5-7: warning: rule useless in parser due to conflicts: reported_conflicts: 'a'
-input-keep.y:33.4: warning: rule useless in parser due to conflicts: reported_conflicts: /* empty */
+[[input-keep.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+input-keep.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+input-keep.y:22.4: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:26.16: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:32.5-7: warning: rule useless in parser due to conflicts [-Wother]
+input-keep.y:33.4: warning: rule useless in parser due to conflicts [-Wother]
]])
AT_CLEANUP
empty_c3: %prec 'd' ;
]])
AT_BISON_CHECK([[--report=all -o input.c input.y]], 0, [], [ignore])
-AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^state 1$/p']], 0,
-[[state 0
+AT_CHECK([[cat input.output | sed -n '/^State 0$/,/^State 1$/p']], 0,
+[[State 0
0 $accept: . start $end
1 start: . 'a'
13 empty_c3: . ['c']
'b' shift, and go to state 1
-
+
'c' reduce using rule 13 (empty_c3)
$default reduce using rule 9 (empty_a)
Conflict between rule 13 and token 'c' resolved as reduce ('c' < 'd').
-state 1
+State 1
]])
AT_CLEANUP
]])
AT_BISON_CHECK([[--report=all -o input.c input.y]], 0, [], [ignore])
-AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^state 1$/p']], 0,
-[[state 0
+AT_CHECK([[cat input.output | sed -n '/^State 0$/,/^State 1$/p']], 0,
+[[State 0
0 $accept: . start $end
1 start: . 'a'
Conflict between rule 11 and token 'c' resolved as an error (%nonassoc 'c').
-state 1
+State 1
]])
AT_CLEANUP
+
+
+## -------------------- ##
+## %expect-rr non GLR. ##
+## -------------------- ##
+
+AT_SETUP([[%expect-rr non GLR]])
+
+AT_DATA([[1.y]],
+[[%expect-rr 0
+%%
+exp: 'a'
+]])
+
+AT_BISON_CHECK([[1.y]], [[0]], [],
+[[1.y: warning: %expect-rr applies only to GLR parsers [-Wother]
+]])
+
+AT_DATA([[2.y]],
+[[%expect-rr 1
+%%
+exp: 'a' | 'a';
+]])
+
+AT_BISON_CHECK([[2.y]], [[0]], [],
+[[2.y: warning: %expect-rr applies only to GLR parsers [-Wother]
+2.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+2.y:3.12-14: warning: rule useless in parser due to conflicts [-Wother]
+]])
+
+AT_CLEANUP
+
+
+## ---------------------------------- ##
+## -W versus %expect and %expect-rr. ##
+## ---------------------------------- ##
+
+AT_SETUP([[-W versus %expect and %expect-rr]])
+
+AT_DATA([[sr-rr.y]],
+[[%glr-parser
+%%
+start: 'a' | A 'a' | B 'a' ;
+A: ;
+B: ;
+]])
+AT_DATA([[sr.y]],
+[[%glr-parser
+%%
+start: 'a' | A 'a' ;
+A: ;
+]])
+AT_DATA([[rr.y]],
+[[%glr-parser
+%%
+start: A | B ;
+A: ;
+B: ;
+]])
+
+AT_BISON_CHECK([[sr-rr.y]], [[0]], [[]],
+[[sr-rr.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+sr-rr.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
+AT_BISON_CHECK([[-Wno-conflicts-sr sr-rr.y]], [[0]], [[]],
+[[sr-rr.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
+AT_BISON_CHECK([[-Wno-conflicts-rr sr-rr.y]], [[0]], [[]],
+[[sr-rr.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+]])
+
+[
+# This is piece of code is rather complex for a simple task: try every
+# combinaison of (0 or 1 real SR) x (0 or 1 real RR) x (don't %expect
+# or %expect 0, 1, or 2 SR) x (don't %expect-rr or %expect-rr 0, 1, or 2
+# RR).
+
+# Number and types of genuine conflicts in the grammar.
+for gram in sr-rr sr rr; do
+ # Number of expected s/r conflicts.
+ for sr_exp_i in '' 0 1 2; do
+ # Number of expected r/r conflicts.
+ for rr_exp_i in '' 0 1 2; do
+ test -z "$sr_exp_i" && test -z "$rr_exp_i" && continue
+
+ # Build grammar file.
+ sr_exp=0
+ rr_exp=0
+ file=$gram
+ directives=
+ if test -n "$sr_exp_i"; then
+ sr_exp=$sr_exp_i
+ file=$file-expect-$sr_exp
+ directives="%expect $sr_exp"
+ fi
+ if test -n "$rr_exp_i"; then
+ rr_exp=$rr_exp_i
+ file=$file-expect-rr-$rr_exp
+ directives="$directives %expect-rr $rr_exp"
+ fi
+ file=$file.y
+ echo "$directives" > $file
+ cat $gram.y >> $file
+
+ # Number of found conflicts.
+ case $gram in
+ (sr) sr_count=1; rr_count=0;;
+ (rr) sr_count=0; rr_count=1;;
+ (sr-rr) sr_count=1; rr_count=1;;
+ esac
+
+ # Update number of expected conflicts: if %expect is given then
+ # %expect-rr defaults to 0, and vice-versa. Leave empty if
+ # nothing expected.
+ case $sr_exp_i:$rr_exp_i in
+ ?:) rr_exp_i=0;;
+ :?) sr_exp_i=0;;
+ esac
+
+ # Run tests.
+ if test $sr_count -eq $sr_exp && test $rr_count -eq $rr_exp; then
+ ]AT_BISON_CHECK([[-Wnone $file]])[
+ ]AT_BISON_CHECK([[-Werror $file]])[
+ else
+ {
+ if test -z "$sr_exp_i" && test "$sr_count" -ne 0; then
+ echo "warning: $sr_count shift/reduce conflicts"
+ elif test "$sr_exp_i" -ne "$sr_count"; then
+ echo "error: shift/reduce conflicts: $sr_count found, $sr_exp_i expected"
+ fi
+ if test -z "$rr_exp_i" && test "$rr_count" -ne 0; then
+ echo "warning: $rr_count reduce/reduce conflicts"
+ elif test "$rr_exp_i" -ne "$rr_count"; then
+ echo "error: reduce/reduce conflicts: $rr_count found, $rr_exp_i expected"
+ fi
+ } | sed -e "s/^/$file: /" > experr
+ ]AT_BISON_CHECK([[-Wnone $file]], [[1]], [[]], [[experr]])[
+ ]AT_BISON_CHECK([[-Werror $file]], [[1]], [[]], [[experr]])[
+ fi
+ done
+ done
+done]
+
+AT_CLEANUP
projects / bison.git / blobdiff