5ed5ae7514
the booleans represent the symbols point to auxiliary tokens or not. This is all we need to know for the purpose of building parse tables. Any other information just leads to redundant parse states.
54 lines
No EOL
1.9 KiB
C++
54 lines
No EOL
1.9 KiB
C++
#include "spec_helper.h"
|
|
#include "build_tables/item_set_closure.h"
|
|
#include "build_tables/item_set_transitions.h"
|
|
#include "grammar.h"
|
|
#include "rules.h"
|
|
|
|
using namespace build_tables;
|
|
using namespace rules;
|
|
|
|
START_TEST
|
|
|
|
describe("computing closures of item sets", []() {
|
|
Grammar grammar({
|
|
{ "E", choice({
|
|
seq({
|
|
sym("T"),
|
|
sym("+"),
|
|
sym("T") }),
|
|
sym("T") }) },
|
|
{ "T", choice({
|
|
seq({
|
|
sym("F"),
|
|
sym("*"),
|
|
sym("F") }),
|
|
sym("F") }) },
|
|
{ "F", choice({
|
|
sym("v"),
|
|
sym("n") }) }
|
|
});
|
|
|
|
it("computes the item set closure", [&]() {
|
|
ParseItemSet item_set = item_set_closure(ParseItemSet({
|
|
ParseItem(Symbol("E"), grammar.rule(Symbol("E")), {}, Symbol("__END__"))
|
|
}), grammar);
|
|
AssertThat(item_set, Equals(ParseItemSet({
|
|
ParseItem(Symbol("F"), grammar.rule(Symbol("F")), {}, Symbol("__END__")),
|
|
ParseItem(Symbol("F"), grammar.rule(Symbol("F")), {}, Symbol("+")),
|
|
ParseItem(Symbol("F"), grammar.rule(Symbol("F")), {}, Symbol("*")),
|
|
ParseItem(Symbol("T"), grammar.rule(Symbol("T")), {}, Symbol("__END__")),
|
|
ParseItem(Symbol("T"), grammar.rule(Symbol("T")), {}, Symbol("+")),
|
|
ParseItem(Symbol("E"), grammar.rule(Symbol("E")), {}, Symbol("__END__")),
|
|
})));
|
|
|
|
auto sym1 = rules::Symbol("v");
|
|
ParseItemSet next_item_set = *sym_transitions(item_set, grammar)[sym1];
|
|
AssertThat(next_item_set, Equals(ParseItemSet({
|
|
ParseItem(Symbol("F"), rules::blank(), { false }, Symbol("__END__")),
|
|
ParseItem(Symbol("F"), rules::blank(), { false }, Symbol("*")),
|
|
ParseItem(Symbol("F"), rules::blank(), { false }, Symbol("+")),
|
|
})));
|
|
});
|
|
});
|
|
|
|
END_TEST |