[bug](bitmap) fix bitmap value copy operator not call reset (#26451)

when a empty bitmap assign to other bitmap
the other bitmap should reset self firstly, and then set empty type.

be/src/util/bitmap_value.h

@@ -1172,10 +1172,11 @@ class BitmapValue {
     using SetContainer = phmap::flat_hash_set<T>;
 
     // Construct an empty bitmap.
-    BitmapValue() : _type(EMPTY), _is_shared(false) {}
+    BitmapValue() : _sv(0), _bitmap(nullptr), _type(EMPTY), _is_shared(false) { _set.clear(); }
 
     // Construct a bitmap with one element.
-    explicit BitmapValue(uint64_t value) : _sv(value), _type(SINGLE), _is_shared(false) {}
+    explicit BitmapValue(uint64_t value)
+            : _sv(value), _bitmap(nullptr), _type(SINGLE), _is_shared(false) {}
 
     // Construct a bitmap from serialized data.
     explicit BitmapValue(const char* src) : _is_shared(false) {
@@ -1199,7 +1200,7 @@ class BitmapValue {
             break;
         }
 
-        if (other._type != EMPTY) {
+        if (other._type == BITMAP) {
             _is_shared = true;
             // should also set other's state to shared, so that other bitmap value will
             // create a new bitmap when it wants to modify it.
@@ -1229,6 +1230,10 @@ class BitmapValue {
     }
 
     BitmapValue& operator=(const BitmapValue& other) {
+        if (this == &other) {
+            return *this;
+        }
+        reset();
         _type = other._type;
         switch (other._type) {
         case EMPTY:
@@ -1244,7 +1249,7 @@ class BitmapValue {
             break;
         }
 
-        if (other._type != EMPTY) {
+        if (other._type == BITMAP) {
             _is_shared = true;
             // should also set other's state to shared, so that other bitmap value will
             // create a new bitmap when it wants to modify it.
@@ -1265,6 +1270,7 @@ class BitmapValue {
         if (this == &other) {
             return *this;
         }
+        reset();
 
         _type = other._type;
         switch (other._type) {
@@ -1721,8 +1727,7 @@ class BitmapValue {
     BitmapValue& operator&=(const BitmapValue& rhs) {
         switch (rhs._type) {
         case EMPTY:
-            _type = EMPTY;
-            _bitmap.reset();
+            reset(); // empty & any = empty
             break;
         case SINGLE:
             switch (_type) {
@@ -1741,6 +1746,7 @@ class BitmapValue {
                     _sv = rhs._sv;
                 }
                 _bitmap.reset();
+                _is_shared = false;
                 break;
             case SET:
                 if (!_set.contains(rhs._sv)) {
@@ -1797,6 +1803,7 @@ class BitmapValue {
                 }
                 _type = SET;
                 _bitmap.reset();
+                _is_shared = false;
                 _convert_to_smaller_type();
                 break;
             case SET:
@@ -1832,7 +1839,6 @@ class BitmapValue {
             case SINGLE:
                 if (_sv == rhs._sv) {
                     _type = EMPTY;
-                    _bitmap.reset();
                 } else {
                     add(rhs._sv);
                 }
@@ -2162,7 +2168,7 @@ class BitmapValue {
 
     // Return how many bytes are required to serialize this bitmap.
     // See BitmapTypeCode for the serialized format.
-    size_t getSizeInBytes() {
+    size_t getSizeInBytes() const {
         size_t res = 0;
         switch (_type) {
         case EMPTY:
@@ -2613,12 +2619,13 @@ class BitmapValue {
         }
     }
 
-    void clear() {
+    void reset() {
         _type = EMPTY;
-        _bitmap.reset();
         _sv = 0;
+        _set.clear();
+        _is_shared = false;
+        _bitmap = nullptr;
     }
-
     // Implement an iterator for convenience
     friend class BitmapValueIterator;
     typedef BitmapValueIterator b_iterator;

be/src/vec/aggregate_functions/aggregate_function_bitmap.h

@@ -143,7 +143,7 @@ struct AggregateFunctionBitmapData {
 
     void reset() {
         is_first = true;
-        value.clear();
+        value.reset(); // it's better to call reset function by self firstly.
     }
 
     BitmapValue& get() { return value; }

be/src/vec/aggregate_functions/aggregate_function_bitmap_agg.h

@@ -46,7 +46,7 @@ struct AggregateFunctionBitmapAggData {
 
     void add(const T& value_) { value.add(value_); }
 
-    void reset() { value.clear(); }
+    void reset() { value.reset(); }
 
     void merge(const AggregateFunctionBitmapAggData& other) { value |= other.value; }
 

be/src/vec/data_types/data_type_bitmap.cpp

@@ -114,9 +114,7 @@ void DataTypeBitMap::to_string(const IColumn& column, size_t row_num, BufferWrit
     ColumnPtr ptr = result.first;
     row_num = result.second;
 
-    auto& data =
-            const_cast<BitmapValue&>(assert_cast<const ColumnBitmap&>(*ptr).get_element(row_num));
-
+    const auto& data = assert_cast<const ColumnBitmap&>(*ptr).get_element(row_num);
     std::string buffer(data.getSizeInBytes(), '0');
     data.write_to(const_cast<char*>(buffer.data()));
     ostr.write(buffer.c_str(), buffer.size());

be/src/vec/data_types/data_type_bitmap.h

@@ -30,6 +30,7 @@
 #include "serde/data_type_bitmap_serde.h"
 #include "util/bitmap_value.h"
 #include "vec/columns/column_complex.h"
+#include "vec/columns/column_const.h"
 #include "vec/core/field.h"
 #include "vec/core/types.h"
 #include "vec/data_types/data_type.h"
@@ -94,7 +95,12 @@ class DataTypeBitMap : public IDataType {
     bool can_be_inside_low_cardinality() const override { return false; }
 
     std::string to_string(const IColumn& column, size_t row_num) const override {
-        return "BitMap()";
+        auto result = check_column_const_set_readability(column, row_num);
+        ColumnPtr ptr = result.first;
+        row_num = result.second;
+
+        const auto& data = assert_cast<const ColumnBitmap&>(*ptr).get_element(row_num);
+        return data.to_string();
     }
     void to_string(const IColumn& column, size_t row_num, BufferWritable& ostr) const override;
     Status from_string(ReadBuffer& rb, IColumn* column) const override;

be/src/vec/functions/function_bitmap.cpp

@@ -578,7 +578,7 @@ struct BitmapAndNot {
             mid_data &= rvec[i];
             res[i] = lvec[i];
             res[i] -= mid_data;
-            mid_data.clear();
+            mid_data.reset();
         }
     }
     static void vector_scalar(const TData& lvec, const BitmapValue& rval, TData& res) {
@@ -589,7 +589,7 @@ struct BitmapAndNot {
             mid_data &= rval;
             res[i] = lvec[i];
             res[i] -= mid_data;
-            mid_data.clear();
+            mid_data.reset();
         }
     }
     static void scalar_vector(const BitmapValue& lval, const TData& rvec, TData& res) {
@@ -600,7 +600,7 @@ struct BitmapAndNot {
             mid_data &= rvec[i];
             res[i] = lval;
             res[i] -= mid_data;
-            mid_data.clear();
+            mid_data.reset();
         }
     }
 };
@@ -624,7 +624,7 @@ struct BitmapAndNotCount {
             mid_data = lvec[i];
             mid_data &= rvec[i];
             res[i] = lvec[i].andnot_cardinality(mid_data);
-            mid_data.clear();
+            mid_data.reset();
         }
     }
     static void scalar_vector(const BitmapValue& lval, const TData& rvec, ResTData* res) {
@@ -634,7 +634,7 @@ struct BitmapAndNotCount {
             mid_data = lval;
             mid_data &= rvec[i];
             res[i] = lval.andnot_cardinality(mid_data);
-            mid_data.clear();
+            mid_data.reset();
         }
     }
     static void vector_scalar(const TData& lvec, const BitmapValue& rval, ResTData* res) {
@@ -644,7 +644,7 @@ struct BitmapAndNotCount {
             mid_data = lvec[i];
             mid_data &= rval;
             res[i] = lvec[i].andnot_cardinality(mid_data);
-            mid_data.clear();
+            mid_data.reset();
         }
     }
 };

be/test/util/bitmap_value_test.cpp

@@ -24,6 +24,7 @@
 #include <cstdint>
 #include <string>
 
+#include "gtest/gtest.h"
 #include "gtest/gtest_pred_impl.h"
 #include "util/coding.h"
 
@@ -422,7 +423,7 @@ TEST(BitmapValueTest, set) {
 
     bitmap_value.add(4294967297);
     EXPECT_EQ(bitmap_value.get_type_code(), BitmapTypeCode::SINGLE64);
-    bitmap_value.clear();
+    bitmap_value.reset();
 
     bitmap_value.add(10);
     EXPECT_EQ(bitmap_value.get_type_code(), BitmapTypeCode::SINGLE32);
@@ -494,7 +495,7 @@ TEST(BitmapValueTest, add) {
     bitmap_value.add_many(values.data(), values.size());
     EXPECT_EQ(bitmap_value.get_type_code(), BitmapTypeCode::BITMAP32);
 
-    bitmap_value.clear();
+    bitmap_value.reset();
     values.clear();
     values.resize(31);
     std::iota(values.begin(), values.end(), 0);
@@ -545,6 +546,39 @@ void check_bitmap_value_operator(const BitmapValue& left, const BitmapValue& rig
     EXPECT_EQ(copy.cardinality(), left_cardinality + right_cardinality - and_cardinality * 2);
 }
 
+// '='
+TEST(BitmapValueTest, copy_operator) {
+    BitmapValue test_bitmap;
+
+    std::vector<uint64_t> values1(31);
+    BitmapValue bitmap;
+    values1.resize(128);
+    std::iota(values1.begin(), values1.begin() + 16, 0);
+    std::iota(values1.begin() + 16, values1.begin() + 32, 4294967297);
+    std::iota(values1.begin() + 32, values1.begin() + 64, 8589934594);
+    std::iota(values1.begin() + 64, values1.end(), 42949672970);
+    bitmap.add_many(values1.data(), values1.size());
+
+    test_bitmap = bitmap; //should be bitmap
+    EXPECT_EQ(test_bitmap.cardinality(), bitmap.cardinality());
+    EXPECT_EQ(test_bitmap.to_string(), bitmap.to_string());
+
+    BitmapValue single(1);
+    test_bitmap = single; //should be single
+    EXPECT_EQ(test_bitmap.cardinality(), 1);
+    EXPECT_EQ(test_bitmap.cardinality(), single.cardinality());
+    EXPECT_EQ(test_bitmap.to_string(), single.to_string());
+
+    BitmapValue empty;
+    test_bitmap = empty; // should be empty
+    EXPECT_TRUE(test_bitmap.empty());
+
+    BitmapValue bitmap2(bitmap);
+    EXPECT_EQ(bitmap2.to_string(), bitmap.to_string());
+    bitmap2 = bitmap;
+    EXPECT_EQ(bitmap2.to_string(), bitmap.to_string());
+}
+
 // '-=', '|=', '&=', '^='
 TEST(BitmapValueTest, operators) {
     config::enable_set_in_bitmap_value = true;
@@ -658,7 +692,7 @@ TEST(BitmapValueTest, write_read) {
     buffer.reset(new char[size]);
 
     bitmap_single.write_to(buffer.get());
-    deserialized.clear();
+    deserialized.reset();
     deserialized.deserialize(buffer.get());
 
     check_bitmap_equal(deserialized, bitmap_single);
@@ -667,7 +701,7 @@ TEST(BitmapValueTest, write_read) {
     buffer.reset(new char[size]);
 
     bitmap_set.write_to(buffer.get());
-    deserialized.clear();
+    deserialized.reset();
     deserialized.deserialize(buffer.get());
 
     check_bitmap_equal(deserialized, bitmap_set);
@@ -676,7 +710,7 @@ TEST(BitmapValueTest, write_read) {
     buffer.reset(new char[size]);
 
     bitmap.write_to(buffer.get());
-    deserialized.clear();
+    deserialized.reset();
     deserialized.deserialize(buffer.get());
 
     check_bitmap_equal(deserialized, bitmap);