YQL-20307: Support inline subqueries

- Alter grammar to support inline subqueries.
- Support inline subqueries in `sql/v1` (translator).
- Introduce `sql/v1/proto_ast/parse_tree.h` for reusable parse tree predicates.
- Support inline subqueries in `sql/v1/format`.
- Support inline subqueries in `sql/v1/complete`.
- Add some SQL-tests.
- Pass all tests.
commit_hash:075b2240778d071e1c7542f912d3cc83019ef849

3 files changed, 129 insertions, 1 deletions

diff --git a/yql/essentials/sql/v1/proto_parser/parse_tree.cpp b/yql/essentials/sql/v1/proto_parser/parse_tree.cpp
new file mode 100644
index 00000000000..a9318368436
--- /dev/null
+++ b/yql/essentials/sql/v1/proto_parser/parse_tree.cpp
@@ -0,0 +1,110 @@
+#include "parse_tree.h"
+
+namespace NSQLTranslationV1 {
+
+    const TRule_select_or_expr* GetSelectOrExpr(const TRule_smart_parenthesis& msg) {
+        if (!msg.GetBlock2().HasAlt1()) {
+            return nullptr;
+        }
+
+        return &msg.GetBlock2()
+                    .GetAlt1()
+                    .GetRule_select_subexpr1()
+                    .GetRule_select_subexpr_intersect1()
+                    .GetRule_select_or_expr1();
+    }
+
+    const TRule_tuple_or_expr* GetTupleOrExpr(const TRule_smart_parenthesis& msg) {
+        const auto* select_or_expr = GetSelectOrExpr(msg);
+        if (!select_or_expr) {
+            return nullptr;
+        }
+
+        if (!select_or_expr->HasAlt_select_or_expr2()) {
+            return nullptr;
+        }
+
+        return &select_or_expr
+                    ->GetAlt_select_or_expr2()
+                    .GetRule_tuple_or_expr1();
+    }
+
+    const TRule_smart_parenthesis* GetParenthesis(const TRule_expr& msg) {
+        if (!msg.HasAlt_expr1()) {
+            return nullptr;
+        }
+
+        const auto& con = msg.GetAlt_expr1()
+                              .GetRule_or_subexpr1()
+                              .GetRule_and_subexpr1()
+                              .GetRule_xor_subexpr1()
+                              .GetRule_eq_subexpr1()
+                              .GetRule_neq_subexpr1()
+                              .GetRule_bit_subexpr1()
+                              .GetRule_add_subexpr1()
+                              .GetRule_mul_subexpr1()
+                              .GetRule_con_subexpr1();
+
+        if (!con.HasAlt_con_subexpr1()) {
+            return nullptr;
+        }
+
+        const auto& unary_subexpr = con.GetAlt_con_subexpr1()
+                                        .GetRule_unary_subexpr1();
+
+        if (!unary_subexpr.HasAlt_unary_subexpr1()) {
+            return nullptr;
+        }
+
+        const auto& block = unary_subexpr.GetAlt_unary_subexpr1()
+                                .GetRule_unary_casual_subexpr1()
+                                .GetBlock1();
+
+        if (!block.HasAlt2()) {
+            return nullptr;
+        }
+
+        const auto& atom = block.GetAlt2()
+                               .GetRule_atom_expr1();
+
+        if (!atom.HasAlt_atom_expr3()) {
+            return nullptr;
+        }
+
+        return &atom.GetAlt_atom_expr3()
+                    .GetRule_lambda1()
+                    .GetRule_smart_parenthesis1();
+    }
+
+    bool IsSelect(const TRule_smart_parenthesis& msg) {
+        const auto* select_or_expr = GetSelectOrExpr(msg);
+        if (!select_or_expr) {
+            return false;
+        }
+
+        if (select_or_expr->HasAlt_select_or_expr1()) {
+            return true;
+        }
+
+        return IsSelect(
+            select_or_expr
+                ->GetAlt_select_or_expr2()
+                .GetRule_tuple_or_expr1()
+                .GetRule_expr1());
+    }
+
+    bool IsSelect(const TRule_expr& msg) {
+        const auto* parenthesis = GetParenthesis(msg);
+        if (!parenthesis) {
+            return false;
+        }
+
+        return IsSelect(*parenthesis);
+    }
+
+    bool IsOnlySubExpr(const TRule_select_subexpr& node) {
+        return node.GetBlock2().size() == 0 &&
+               node.GetRule_select_subexpr_intersect1().GetBlock2().size() == 0;
+    }
+
+} // namespace NSQLTranslationV1
diff --git a/yql/essentials/sql/v1/proto_parser/parse_tree.h b/yql/essentials/sql/v1/proto_parser/parse_tree.h
new file mode 100644
index 00000000000..74936d90466
--- /dev/null
+++ b/yql/essentials/sql/v1/proto_parser/parse_tree.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <yql/essentials/parser/proto_ast/gen/v1_proto_split/SQLv1Parser.pb.main.h>
+
+namespace NSQLTranslationV1 {
+
+    using namespace NSQLv1Generated;
+
+    const TRule_tuple_or_expr* GetTupleOrExpr(const TRule_smart_parenthesis& msg);
+
+    bool IsSelect(const TRule_smart_parenthesis& msg);
+
+    bool IsSelect(const TRule_expr& msg);
+
+    bool IsOnlySubExpr(const TRule_select_subexpr& msg);
+
+} // namespace NSQLTranslationV1
diff --git a/yql/essentials/sql/v1/proto_parser/ya.make b/yql/essentials/sql/v1/proto_parser/ya.make
index d87741f8a91..0fbe9f45469 100644
--- a/yql/essentials/sql/v1/proto_parser/ya.make
+++ b/yql/essentials/sql/v1/proto_parser/ya.make
@@ -3,9 +3,11 @@ LIBRARY()
 PEERDIR(
     yql/essentials/utils
     yql/essentials/parser/proto_ast/collect_issues
+    yql/essentials/parser/proto_ast/gen/v1_proto_split
 )
 
 SRCS(
+    parse_tree.cpp
     proto_parser.cpp
 )
 
@@ -17,4 +19,3 @@ RECURSE(
     antlr4
     antlr4_ansi
 )
-