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Improve handling of multiple S/R conflicts in the same state and of S/R

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conflicts involving multiple reductions.
* src/conflicts.c (resolve_sr_conflict): Don't assign the error action
set for a state here or Bison will abort if it is reassigned on a
later conflicted reduction in the same state.
Similarly, don't finalize and assign the solved conflicts report here
or it will be lost if it is reassigned on a later conflicted reduction
in the same state.
(set_conflicts): Instead, assign them both here after all S/R conflicts
in the state have been fully examined.
* src/print.c (shift_set): Rename to...
(no_reduce_set): ... this.
(print_reductions): Update for rename, and add %nonassoc error action
tokens to no_reduce_set so that, when printing the first remaining
reduction on an error action token, the reduction is enclosed in
brackets.
(print_results): Update for rename.
* tests/conflicts.at (Solved conflicts report for multiple reductions
in a state): New test case.
(%nonassoc error actions for multiple reductions in a state): New test
case.

* src/main.c (main): Don't depend on C99 features.
This commit is contained in:
Joel E. Denny
2007-07-17 06:56:36 +00:00
parent b541ffdf2c
commit 9d774affba
5 changed files with 211 additions and 33 deletions
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153
tests/conflicts.at
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@@ -90,7 +90,7 @@ expr: expr '<' expr
int
main (int argc, const char *argv[])
{
input = argc <= 1 ? "" : argv[1];
input = argc <= 1 ? "" : argv[1];
return yyparse ();
}
]])
@@ -810,8 +810,157 @@ state 6
state 7
1 start: resolved_conflict 'a' reported_conflicts 'a' .
$default reduce using rule 1 (start)
]])
AT_CLEANUP
## ------------------------------------------------------------ ##
## Solved conflicts report for multiple reductions in a state. ##
## ------------------------------------------------------------ ##
AT_SETUP([[Solved conflicts report for multiple reductions in a state]])
# Used to lose earlier solved conflict messages even within a single S/R/R.
AT_DATA([[input.y]],
[[%left 'a'
%right 'b'
%right 'c'
%right 'd'
%%
start:
'a'
| empty_a 'a'
| 'b'
| empty_b 'b'
| 'c'
| empty_c1 'c'
| empty_c2 'c'
| empty_c3 'c'
;
empty_a: %prec 'a' ;
empty_b: %prec 'b' ;
empty_c1: %prec 'c' ;
empty_c2: %prec 'c' ;
empty_c3: %prec 'd' ;
]])
AT_CHECK([[bison --report=all -o input.c input.y]], 0, [], [ignore])
AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^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)
$default reduce using rule 9 (empty_a)
start go to state 2
empty_a go to state 3
empty_b go to state 4
empty_c1 go to state 5
empty_c2 go to state 6
empty_c3 go to state 7
Conflict between rule 9 and token 'a' resolved as reduce (%left 'a').
Conflict between rule 10 and token 'b' resolved as shift (%right 'b').
Conflict between rule 11 and token 'c' resolved as shift (%right 'c').
Conflict between rule 12 and token 'c' resolved as shift (%right 'c').
Conflict between rule 13 and token 'c' resolved as reduce ('c' < 'd').
state 1
]])
AT_CLEANUP
## ------------------------------------------------------------ ##
## %nonassoc error actions for multiple reductions in a state. ##
## ------------------------------------------------------------ ##
# Used to abort when trying to resolve conflicts as %nonassoc error actions for
# multiple reductions in a state.
# For a %nonassoc error action token, used to print the first remaining
# reduction on that token without brackets.
AT_SETUP([[%nonassoc error actions for multiple reductions in a state]])
AT_DATA([[input.y]],
[[%nonassoc 'a' 'b' 'c'
%%
start:
'a'
| empty_a 'a'
| 'b'
| empty_b 'b'
| 'c'
| empty_c1 'c'
| empty_c2 'c'
| empty_c3 'c'
;
empty_a: %prec 'a' ;
empty_b: %prec 'b' ;
empty_c1: %prec 'c' ;
empty_c2: %prec 'c' ;
empty_c3: %prec 'c' ;
]])
AT_CHECK([[bison --report=all -o input.c input.y]], 0, [], [ignore])
AT_CHECK([[cat input.output | sed -n '/^state 0$/,/^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