tree-sitter/spec/compiler/build_tables/item_set_closure_spec.cpp

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1.8 KiB
C++

#include "spec_helper.h"
#include "build_tables/item_set_closure.h"
#include "build_tables/item_set_transitions.h"
using namespace build_tables;
using namespace rules;
START_TEST
describe("computing closures of item sets", []() {
Grammar grammar("E", {
{ "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__")),
})));
ParseItemSet next_item_set = sym_transitions(item_set, grammar)[Symbol("v")];
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