tree-sitter/spec/runtime/lr_parser_spec.cc

105 lines
No EOL
2.9 KiB
C++

#include "runtime_spec_helper.h"
#include "helpers/spy_reader.h"
#include "tree_sitter/parser/lr_parser.h"
enum {
sym1 = 2,
sym2 = 3,
hidden_sym = 4,
};
const ts_parse_action parse_table[3][5] = {
[0] = {
[sym2] = SHIFT(12),
[hidden_sym] = SHIFT(12),
},
[1] = {
[sym1] = ACCEPT_INPUT(),
[sym2] = SHIFT(2),
[hidden_sym] = SHIFT(4),
},
[2] = {
[sym1] = SHIFT(3),
[sym2] = SHIFT(12),
[hidden_sym] = SHIFT(12),
},
};
ts_state_id lex_states[3] = {
[0] = 100,
[1] = 101,
[2] = 102,
};
int hidden_symbols[5] = {
[sym1] = 0,
[sym2] = 0,
[hidden_sym] = 1,
};
ts_tree *lex_fn_node_to_return;
ts_state_id lex_fn_state_received;
ts_lexer *lex_fn_lexer_received;
ts_tree * fake_lex(ts_lexer *lexer, ts_state_id state_id) {
lex_fn_lexer_received = lexer;
lex_fn_state_received = state_id;
return lex_fn_node_to_return;
}
START_TEST
describe("LR Parsers", [&]() {
ts_lr_parser *parser;
SpyReader *reader;
before_each([&]() {
reader = new SpyReader("some structured text", 5);
parser = ts_lr_parser_make(3, (const ts_parse_action *)parse_table, lex_states, fake_lex, hidden_symbols, nullptr);
});
after_each([&]() {
delete reader;
});
describe("when starting at the beginning of the input (edit is NULL)", [&]() {
before_each([&]() {
ts_lr_parser_initialize(parser, reader->input, nullptr);
});
it("runs the lexer with the lex state corresponding to the initial state", [&]() {
lex_fn_node_to_return = ts_tree_make_leaf(sym2, 5, 1);
ts_lr_parser_parse(parser, nullptr);
AssertThat(lex_fn_state_received, Equals(100));
});
describe("when the returned symbol indicates a shift action", [&]() {
before_each([&]() {
lex_fn_node_to_return = ts_tree_make_leaf(sym2, 5, 1);
});
it("advances to the state specified in the action", [&]() {
ts_lr_parser_parse(parser, nullptr);
AssertThat(ts_stack_top_state(&parser->stack), Equals(12));
});
it("continues parsing (returns NULL)", [&]() {
auto result = ts_lr_parser_parse(parser, nullptr);
AssertThat(result, Equals((ts_tree *)nullptr));
});
});
describe("when the returned symbol indicates an error", [&]() {
before_each([&]() {
lex_fn_node_to_return = ts_tree_make_leaf(sym1, 5, 1);
});
it("ends the parse, returning an error tree", [&]() {
auto result = ts_lr_parser_parse(parser, nullptr);
AssertThat(ts_tree_symbol(result), Equals(ts_builtin_sym_error));
});
});
});
});
END_TEST