ORC-1884: [C++] Add a maybe() API to the SearchArgumentBuilder

c++/include/orc/sargs/SearchArgument.hh

@@ -251,6 +251,12 @@ namespace orc {
      * @return the new SearchArgument
      */
     virtual std::unique_ptr<SearchArgument> build() = 0;
+
+    /**
+     * Add a maybe leaf to the current item on the stack.
+     * @return this
+     */
+    virtual SearchArgumentBuilder& maybe() = 0;
   };
 
   /**

c++/src/sargs/SearchArgument.cc

@@ -272,6 +272,12 @@ namespace orc {
     return *this;
   }
 
+  SearchArgumentBuilder& SearchArgumentBuilderImpl::maybe() {
+    TreeNode& parent = currTree_.front();
+    parent->addChild(std::make_shared<ExpressionTree>(TruthValue::YES_NO_NULL));
+    return *this;
+  }
+
   /**
    * Recursively explore the tree to find the leaves that are still reachable
    * after optimizations.

c++/src/sargs/SearchArgument.hh

@@ -275,6 +275,12 @@ namespace orc {
      */
     std::unique_ptr<SearchArgument> build() override;
 
+    /**
+     * Add a maybe leaf to the current item on the stack.
+     * @return this
+     */
+    SearchArgumentBuilder& maybe() override;
+
    private:
     SearchArgumentBuilder& start(ExpressionTree::Operator op);
     size_t addLeaf(PredicateLeaf leaf);

c++/test/TestSearchArgument.cc

@@ -490,4 +490,36 @@ namespace orc {
     EXPECT_THROW(invalidNode->evaluate(leaves), std::invalid_argument);
   }
 
+  TEST(TestSearchArgument, testMaybe) {
+    auto expectedSarg =
+        SearchArgumentFactory::newBuilder()
+            ->startNot()
+            .startOr()
+            .isNull("x", PredicateDataType::LONG)
+            .between("y", PredicateDataType::DECIMAL, Literal(10, 3, 0), Literal(200, 3, 1))
+            .in("z", PredicateDataType::LONG,
+                {Literal(static_cast<int64_t>(1)), Literal(static_cast<int64_t>(2)),
+                 Literal(static_cast<int64_t>(3))})
+            .nullSafeEquals("a", PredicateDataType::STRING, Literal("stinger", 7))
+            .end()
+            .end()
+            .build();
+
+    auto sargWithMaybe =
+        SearchArgumentFactory::newBuilder()
+            ->startNot()
+            .startOr()
+            .isNull("x", PredicateDataType::LONG)
+            .between("y", PredicateDataType::DECIMAL, Literal(10, 3, 0), Literal(200, 3, 1))
+            .in("z", PredicateDataType::LONG,
+                {Literal(static_cast<int64_t>(1)), Literal(static_cast<int64_t>(2)),
+                 Literal(static_cast<int64_t>(3))})
+            .maybe()
+            .nullSafeEquals("a", PredicateDataType::STRING, Literal("stinger", 7))
+            .end()
+            .end()
+            .build();
+    EXPECT_EQ(expectedSarg->toString(), sargWithMaybe->toString());
+  }
+
 }  // namespace orc