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Handle multiple ubiquitous in a row

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This commit is contained in:
Max Brunsfeld 2014-08-31 12:10:31 -07:00
parent a75686b017
commit 85d8c9df5c
4 changed files with 144 additions and 39 deletions
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57
src/runtime/parser.c
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@ -110,8 +110,15 @@ static void reduce(TSParser *parser, TSSymbol symbol, size_t child_count) {
}
static int reduce_extra(TSParser *parser, TSSymbol symbol) {
TSTree *top_node = ts_stack_top_node(&parser->stack);
if (top_node->symbol == symbol && !ts_tree_is_extra(top_node)) {
TSTree *last_node = NULL;
TS_STACK_FROM_TOP(parser->stack, entry, i) {
if (!ts_tree_is_extra(entry->node)) {
last_node = entry->node;
break;
}
}
if (last_node && last_node->symbol == symbol) {
reduce(parser, symbol, 1);
ts_tree_set_extra(parser->lookahead);
return 1;
@ -136,28 +143,13 @@ static int handle_error(TSParser *parser) {
for (;;) {
/*
* If there is no state in the stack for which we can recover with the
* current lookahead token, advance to the next token. If no characters
* were consumed, advance the lexer to the next character.
*/
size_t prev_position = ts_lexer_position(&parser->lexer);
lex(parser, ts_lex_state_error);
if (ts_lexer_position(&parser->lexer) == prev_position)
if (!ts_lexer_advance(&parser->lexer)) {
DEBUG_PARSE("FAIL TO RECOVER");
ts_stack_push(&parser->stack, 0, error);
ts_tree_release(error);
return 0;
}
/*
* Unwind the parse stack until a state is found in which an error is
* expected and the current lookahead token is expected afterwards.
*/
size_t error_start_pos = last_token_end;
for (size_t i = parser->stack.size - 1; i + 1 > 0; i--) {
TSStateId state = parser->stack.entries[i].state;
TS_STACK_FROM_TOP(parser->stack, entry, i) {
TSStateId state = entry->state;
TSParseAction action_on_error =
actions_for_state(parser->language, state)[ts_builtin_sym_error];
@ -168,7 +160,8 @@ static int handle_error(TSParser *parser) {
if (action_after_error.type != TSParseActionTypeError) {
DEBUG_PARSE("RECOVER %u", state_after_error);
error->size = ts_lexer_position(&parser->lexer) - error_start_pos - 1;
size_t current_position = ts_lexer_position(&parser->lexer);
error->size = current_position - 1 - error_start_pos;
ts_stack_shrink(&parser->stack, i + 1);
ts_stack_push(&parser->stack, state_after_error, error);
ts_tree_release(error);
@ -176,9 +169,25 @@ static int handle_error(TSParser *parser) {
}
}
TSTree *removed_tree = parser->stack.entries[i].node;
TSTree *removed_tree = entry->node;
error_start_pos -= ts_tree_total_size(removed_tree);
}
/*
* If there is no state in the stack for which we can recover with the
* current lookahead token, advance to the next token. If no characters
* were consumed, advance the lexer to the next character.
*/
size_t prev_position = ts_lexer_position(&parser->lexer);
lex(parser, ts_lex_state_error);
parser->lookahead->padding = 0;
if (ts_lexer_position(&parser->lexer) == prev_position)
if (!ts_lexer_advance(&parser->lexer)) {
DEBUG_PARSE("FAIL TO RECOVER");
ts_stack_push(&parser->stack, 0, error);
ts_tree_release(error);
return 0;
}
}
}
@ -256,8 +265,12 @@ const TSTree *ts_parser_parse(TSParser *parser, TSInput input,
break;
case TSParseActionTypeReduceExtra:
if (!reduce_extra(parser, action.data.symbol)) {
DEBUG_PARSE("ERROR");
if (!handle_error(parser))
return get_root(parser);
}
DEBUG_PARSE("REDUCE EXTRA");
reduce_extra(parser, action.data.symbol);
break;
case TSParseActionTypeAccept: