fix 'Unmatched parentheses', add test

src/Parsers/TokenIterator.cpp

@@ -4,13 +4,14 @@
 namespace DB
 {
 
-UnmatchedParentheses checkUnmatchedParentheses(TokenIterator begin, Token last)
+UnmatchedParentheses checkUnmatchedParentheses(TokenIterator begin)
 {
     /// We have just two kind of parentheses: () and [].
     UnmatchedParentheses stack;
 
-    for (TokenIterator it = begin;
-        it.isValid() && it->begin <= last.begin; ++it)
+    /// We have to iterate through all tokens until the end to avoid false positive "Unmatched parentheses" error
+    /// when parser failed in the middle of the query.
+    for (TokenIterator it = begin; it.isValid(); ++it)
     {
         if (it->type == TokenType::OpeningRoundBracket || it->type == TokenType::OpeningSquareBracket)
         {

src/Parsers/TokenIterator.h

@@ -80,6 +80,6 @@ public:
 
 /// Returns positions of unmatched parentheses.
 using UnmatchedParentheses = std::vector<Token>;
-UnmatchedParentheses checkUnmatchedParentheses(TokenIterator begin, Token last);
+UnmatchedParentheses checkUnmatchedParentheses(TokenIterator begin);
 
 }

src/Parsers/parseQuery.cpp

@@ -290,7 +290,7 @@ ASTPtr tryParseQuery(
     }
 
     /// Unmatched parentheses
-    UnmatchedParentheses unmatched_parens = checkUnmatchedParentheses(TokenIterator(tokens), last_token);
+    UnmatchedParentheses unmatched_parens = checkUnmatchedParentheses(TokenIterator(tokens));
     if (!unmatched_parens.empty())
     {
         out_error_message = getUnmatchedParenthesesErrorMessage(query_begin,

tests/queries/0_stateless/01180_client_syntax_errors.expect

@@ -0,0 +1,32 @@
+#!/usr/bin/expect -f
+
+log_user 0
+set timeout 5
+match_max 100000
+# A default timeout action is to do nothing, change it to fail
+expect_after {
+    timeout {
+        exit 1
+    }
+}
+
+set basedir [file dirname $argv0]
+spawn bash -c "source $basedir/../shell_config.sh ; \$CLICKHOUSE_CLIENT_BINARY \$CLICKHOUSE_CLIENT_OPT"
+expect ":) "
+
+# Make a query with syntax error
+send -- "select \r"
+expect "Syntax error: failed at position 7 (end of query):"
+expect "Expected one of: "
+
+# Make another query with syntax error
+send -- "CREATE TABLE t4 UUID '57f27aa5-141c-47c5-888a-9563681717f5' AS t1 (`rowNumberInAllBlocks()` UInt64, `toLowCardinality(arrayJoin(\['exchange', 'tables'\]))` LowCardinality(String)) ENGINE = MergeTree \r"
+expect "Syntax error: failed at position 93 ('UInt64'):*"
+
+# Make a query with unmatched parentheses
+send -- "select (1, 2\r"
+expect "Syntax error: failed at position 8 ('('):"
+expect "Unmatched parentheses: ("
+
+send -- "\4"
+expect eof