Merge pull request #30552 from kawa-yoiko/match-unreachable

Fix unreachable code detection in match statements
This commit is contained in:
Rémi Verschelde 2019-07-15 08:13:57 +02:00 committed by GitHub
commit 75f2575f28
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@ -2211,6 +2211,8 @@ void GDScriptParser::_parse_pattern_block(BlockNode *p_block, Vector<PatternBran
p_block->has_return = true;
bool catch_all_appeared = false;
while (true) {
while (tokenizer->get_token() == GDScriptTokenizer::TK_NEWLINE && _parse_newline())
@ -2221,7 +2223,7 @@ void GDScriptParser::_parse_pattern_block(BlockNode *p_block, Vector<PatternBran
return;
if (indent_level > tab_level.back()->get()) {
return; // go back a level
break; // go back a level
}
if (pending_newline != -1) {
@ -2236,12 +2238,20 @@ void GDScriptParser::_parse_pattern_block(BlockNode *p_block, Vector<PatternBran
branch->patterns.push_back(_parse_pattern(p_static));
if (!branch->patterns[0]) {
return;
break;
}
bool has_binding = branch->patterns[0]->pt_type == PatternNode::PT_BIND;
bool catch_all = has_binding || branch->patterns[0]->pt_type == PatternNode::PT_WILDCARD;
#ifdef DEBUG_ENABLED
// Branches after a wildcard or binding are unreachable
if (catch_all_appeared && !current_function->has_unreachable_code) {
_add_warning(GDScriptWarning::UNREACHABLE_CODE, -1, current_function->name.operator String());
current_function->has_unreachable_code = true;
}
#endif
while (tokenizer->get_token() == GDScriptTokenizer::TK_COMMA) {
tokenizer->advance();
branch->patterns.push_back(_parse_pattern(p_static));
@ -2259,6 +2269,8 @@ void GDScriptParser::_parse_pattern_block(BlockNode *p_block, Vector<PatternBran
catch_all = catch_all || pt == PatternNode::PT_WILDCARD;
}
catch_all_appeared = catch_all_appeared || catch_all;
if (!_enter_indent_block()) {
_set_error("Expected block in pattern branch");
return;
@ -2274,6 +2286,11 @@ void GDScriptParser::_parse_pattern_block(BlockNode *p_block, Vector<PatternBran
p_branches.push_back(branch);
}
// Even if all branches return, there is possibility of default fallthrough
if (!catch_all_appeared) {
p_block->has_return = false;
}
}
void GDScriptParser::_generate_pattern(PatternNode *p_pattern, Node *p_node_to_match, Node *&p_resulting_node, Map<StringName, Node *> &p_bindings) {