YQL-19747 Complete Function Names

- Function names are suggested now
- Changed the module structure
- Checking ruleIndex independence on mode (ansi | default) via unit tests

---

Pull Request resolved: https://github.com/ytsaurus/ytsaurus/pull/1163
commit_hash:1b1a27d2cff8db663c5c7e8efb57896476823315

1 files changed, 65 insertions, 0 deletions

diff --git a/yql/essentials/sql/v1/complete/syntax/parser_call_stack.cpp b/yql/essentials/sql/v1/complete/syntax/parser_call_stack.cpp
new file mode 100644
index 00000000000..855d9af1601
--- /dev/null
+++ b/yql/essentials/sql/v1/complete/syntax/parser_call_stack.cpp
@@ -0,0 +1,65 @@
+#include "parser_call_stack.h"
+
+#include "grammar.h"
+
+#include <util/generic/vector.h>
+#include <util/generic/algorithm.h>
+#include <util/generic/yexception.h>
+
+namespace NSQLComplete {
+
+    const TVector<TRuleId> KeywordRules = {
+        RULE(Keyword),
+        RULE(Keyword_expr_uncompat),
+        RULE(Keyword_table_uncompat),
+        RULE(Keyword_select_uncompat),
+        RULE(Keyword_alter_uncompat),
+        RULE(Keyword_in_uncompat),
+        RULE(Keyword_window_uncompat),
+        RULE(Keyword_hint_uncompat),
+        RULE(Keyword_as_compat),
+        RULE(Keyword_compat),
+    };
+
+    const TVector<TRuleId> TypeNameRules = {
+        RULE(Type_name_simple),
+    };
+
+    const TVector<TRuleId> FunctionNameRules = {
+        RULE(Id_expr),
+        RULE(An_id_or_type),
+        RULE(Id_or_type),
+    };
+
+    bool EndsWith(const TParserCallStack& suffix, const TParserCallStack& stack) {
+        if (stack.size() < suffix.size()) {
+            return false;
+        }
+        const size_t prefixSize = stack.size() - suffix.size();
+        return Equal(std::begin(stack) + prefixSize, std::end(stack), std::begin(suffix));
+    }
+
+    bool ContainsRule(TRuleId rule, const TParserCallStack& stack) {
+        return Find(stack, rule) != std::end(stack);
+    }
+
+    bool IsLikelyTypeStack(const TParserCallStack& stack) {
+        return EndsWith({RULE(Type_name_simple)}, stack);
+    }
+
+    bool IsLikelyFunctionStack(const TParserCallStack& stack) {
+        return EndsWith({RULE(Unary_casual_subexpr), RULE(Id_expr)}, stack) ||
+               EndsWith({RULE(Unary_casual_subexpr),
+                         RULE(Atom_expr),
+                         RULE(An_id_or_type)}, stack);
+    }
+
+    std::unordered_set<TRuleId> GetC3PreferredRules() {
+        std::unordered_set<TRuleId> preferredRules;
+        preferredRules.insert(std::begin(KeywordRules), std::end(KeywordRules));
+        preferredRules.insert(std::begin(TypeNameRules), std::end(TypeNameRules));
+        preferredRules.insert(std::begin(FunctionNameRules), std::end(FunctionNameRules));
+        return preferredRules;
+    }
+
+} // namespace NSQLComplete