Fix backtick matching for antlr4 (#8941)

Author: OrlovPavel

ydb/library/yql/sql/v1/SQLv1Antlr4.g.in

@@ -2049,7 +2049,7 @@ STRING_VALUE: ((STRING_SINGLE | STRING_DOUBLE | STRING_MULTILINE) (S | U | Y | J
 
 ID_PLAIN: ('a'..'z' | 'A'..'Z' | '_') ('a'..'z' | 'A'..'Z' | '_' | DIGIT)*;
 
-fragment ID_QUOTED_CORE: '``' | '\\`' | ~'`';
+fragment ID_QUOTED_CORE: '\\'. | '``' | ~('`' | '\\');
 ID_QUOTED: BACKTICK ID_QUOTED_CORE* BACKTICK;
 
 fragment DIGIT: '0'..'9';

ydb/library/yql/sql/v1/sql_ut.cpp

@@ -7203,6 +7203,30 @@ Y_UNIT_TEST_SUITE(ResourcePoolClassifier) {
 
         UNIT_ASSERT_VALUES_EQUAL(1, elementStat["Write"]);
     }
+
+    Y_UNIT_TEST(BacktickMatching) {
+        auto req = "select\n"
+                   "    1 as `Schema has \\`RealCost\\``\n"
+                   "    -- foo`bar";
+        auto res = SqlToYql(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+        res = SqlToYqlWithAnsiLexer(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+
+        req = "select 1 as `a``b`, 2 as ````, 3 as `\\x60a\\x60`, 4 as ```b```, 5 as `\\`c\\``";
+        res = SqlToYql(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+        res = SqlToYqlWithAnsiLexer(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+    }
 }
 
 Y_UNIT_TEST_SUITE(OlapPartitionCount) {

ydb/library/yql/sql/v1/sql_ut_antlr4.cpp

@@ -7200,4 +7200,28 @@ Y_UNIT_TEST_SUITE(ResourcePoolClassifier) {
 
         UNIT_ASSERT_VALUES_EQUAL(1, elementStat["Write"]);
     }
+
+    Y_UNIT_TEST(BacktickMatching) {
+        auto req = "select\n"
+                   "    1 as `Schema has \\`RealCost\\``\n"
+                   "    -- foo`bar";
+        auto res = SqlToYql(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+        res = SqlToYqlWithAnsiLexer(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+
+        req = "select 1 as `a``b`, 2 as ````, 3 as `\\x60a\\x60`, 4 as ```b```, 5 as `\\`c\\``";
+        res = SqlToYql(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+        res = SqlToYqlWithAnsiLexer(req);
+        UNIT_ASSERT(res.Root);
+        UNIT_ASSERT(res.IsOk());
+        UNIT_ASSERT(res.Issues.Size() == 0);
+    }
 }