[CALCITE-5948] Use explicit casting if element type in ARRAY/MAP does not equal derived component type

babel/src/test/resources/sql/big-query.iq

@@ -1012,9 +1012,9 @@ FROM
 
 SELECT
   email,
-  REGEXP_CONTAINS(email, '^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)$')
+  REGEXP_CONTAINS(email, '^([\w.+-]+@foo\.com|[\w.+-]+@bar\.org)\s+$')
     AS valid_email_address,
-  REGEXP_CONTAINS(email, '^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org$')
+  REGEXP_CONTAINS(email, '^[\w.+-]+@foo\.com|[\w.+-]+@bar\.org\s+$')
     AS without_parentheses
 FROM
   (SELECT

core/src/main/java/org/apache/calcite/sql/fun/SqlArrayValueConstructor.java

@@ -20,6 +20,7 @@
 import org.apache.calcite.sql.SqlKind;
 import org.apache.calcite.sql.SqlOperatorBinding;
 import org.apache.calcite.sql.type.SqlTypeUtil;
+import org.apache.calcite.sql.validate.SqlValidatorUtil;
 
 import static java.util.Objects.requireNonNull;
 
@@ -38,6 +39,10 @@ public SqlArrayValueConstructor() {
             opBinding.getTypeFactory(),
             opBinding.collectOperandTypes());
     requireNonNull(type, "inferred array element type");
+
+    // explicit cast elements to component type if they are not same
+    SqlValidatorUtil.adjustTypeForArrayConstructor(type, opBinding);
+
     return SqlTypeUtil.createArrayType(
         opBinding.getTypeFactory(), type, false);
   }

core/src/main/java/org/apache/calcite/sql/fun/SqlLibraryOperators.java

@@ -43,6 +43,7 @@
 import org.apache.calcite.sql.type.SqlTypeTransforms;
 import org.apache.calcite.sql.type.SqlTypeUtil;
 import org.apache.calcite.sql.validate.SqlValidator;
+import org.apache.calcite.sql.validate.SqlValidatorUtil;
 import org.apache.calcite.util.Litmus;
 import org.apache.calcite.util.Optionality;
 import org.apache.calcite.util.Static;
@@ -1060,6 +1061,10 @@ private static RelDataType arrayReturnType(SqlOperatorBinding opBinding) {
               : opBinding.getTypeFactory().createUnknownType();
     }
     requireNonNull(type, "inferred array element type");
+
+    // explicit cast elements to component type if they are not same
+    SqlValidatorUtil.adjustTypeForArrayConstructor(type, opBinding);
+
     return SqlTypeUtil.createArrayType(opBinding.getTypeFactory(), type, false);
   }
 

core/src/main/java/org/apache/calcite/sql/fun/SqlMapValueConstructor.java

@@ -22,6 +22,7 @@
 import org.apache.calcite.sql.SqlKind;
 import org.apache.calcite.sql.SqlOperatorBinding;
 import org.apache.calcite.sql.type.SqlTypeUtil;
+import org.apache.calcite.sql.validate.SqlValidatorUtil;
 import org.apache.calcite.util.Pair;
 import org.apache.calcite.util.Util;
 
@@ -44,10 +45,15 @@ public SqlMapValueConstructor() {
     super("MAP", SqlKind.MAP_VALUE_CONSTRUCTOR);
   }
 
+  @SuppressWarnings("argument.type.incompatible")
   @Override public RelDataType inferReturnType(SqlOperatorBinding opBinding) {
     Pair<@Nullable RelDataType, @Nullable RelDataType> type =
         getComponentTypes(
             opBinding.getTypeFactory(), opBinding.collectOperandTypes());
+
+    // explicit cast elements to component type if they are not same
+    SqlValidatorUtil.adjustTypeForMapConstructor(type, opBinding);
+
     return SqlTypeUtil.createMapType(
         opBinding.getTypeFactory(),
         requireNonNull(type.left, "inferred key type"),

core/src/main/java/org/apache/calcite/sql/validate/SqlValidatorUtil.java

@@ -38,6 +38,7 @@
 import org.apache.calcite.schema.impl.AbstractSchema;
 import org.apache.calcite.schema.impl.AbstractTable;
 import org.apache.calcite.sql.SqlCall;
+import org.apache.calcite.sql.SqlCallBinding;
 import org.apache.calcite.sql.SqlDataTypeSpec;
 import org.apache.calcite.sql.SqlDynamicParam;
 import org.apache.calcite.sql.SqlFunctionCategory;
@@ -48,6 +49,7 @@
 import org.apache.calcite.sql.SqlNode;
 import org.apache.calcite.sql.SqlNodeList;
 import org.apache.calcite.sql.SqlOperator;
+import org.apache.calcite.sql.SqlOperatorBinding;
 import org.apache.calcite.sql.SqlOperatorTable;
 import org.apache.calcite.sql.SqlSelect;
 import org.apache.calcite.sql.SqlSyntax;
@@ -1309,6 +1311,93 @@ public static boolean isMeasure(SqlNode selectItem) {
     return null;
   }
 
+  /**
+   * When the array element does not equal the array component type, make explicit casting.
+   *
+   * @param componentType derived array component type
+   * @param opBinding description of call
+   */
+  public static void adjustTypeForArrayConstructor(
+      RelDataType componentType, SqlOperatorBinding opBinding) {
+    if (opBinding instanceof SqlCallBinding) {
+      requireNonNull(componentType, "array component type");
+      adjustTypeForMultisetConstructor(
+          componentType, componentType, (SqlCallBinding) opBinding);
+    }
+  }
+
+  /**
+   * When the map key or value does not equal the map component key type or value type,
+   * make explicit casting.
+   *
+   * @param componentType derived map pair component type
+   * @param opBinding description of call
+   */
+  public static void adjustTypeForMapConstructor(
+      Pair<RelDataType, RelDataType> componentType, SqlOperatorBinding opBinding) {
+    if (opBinding instanceof SqlCallBinding) {
+      requireNonNull(componentType.getKey(), "map key type");
+      requireNonNull(componentType.getValue(), "map value type");
+      adjustTypeForMultisetConstructor(
+          componentType.getKey(), componentType.getValue(), (SqlCallBinding) opBinding);
+    }
+  }
+
+  /**
+   * Adjusts the types for operands in a SqlCallBinding during the construction of a sql collection
+   * type such as Array or Map. This method iterates from the operands of a {@link SqlCall}
+   * obtained from the provided {@link SqlCallBinding}.
+   * It modifies each operand to match the specified 'evenType' or 'oddType' depending on whether
+   * the operand's position is even or odd, respectively. The type adjustment is performed by
+   * explicitly casting each operand to the desired type if the existing operand type does not
+   * match the desired type without considering field names.
+   * If we adjust array, we should set 'evenType' and 'oddType' to same desired type,
+   * if we adjust map, we should set 'evenType' as map key type and 'oddType' as map value type.
+   *
+   * <p>For example, if the operand types are {@code [INT, STRING, INT, STRING]}
+   * with {@code evenType} as {@code BOOLEAN} and {@code oddType} as {@code DOUBLE},
+   * after executing this method, the types should be {@code [BOOLEAN, DOUBLE, BOOLEAN, DOUBLE]},
+   * then the corresponding operands are cast to these types.
+   *
+   * @param evenType the {@link RelDataType} to which the operands at even positions should be cast
+   * @param oddType the {@link RelDataType} to which the operands at odd positions should be cast
+   * @param sqlCallBinding the {@link SqlCallBinding} containing the operands to be adjusted
+   */
+  private static void adjustTypeForMultisetConstructor(
+      RelDataType evenType, RelDataType oddType, SqlCallBinding sqlCallBinding) {
+    SqlCall call = sqlCallBinding.getCall();
+    List<RelDataType> operandTypes = sqlCallBinding.collectOperandTypes();
+    List<SqlNode> operands = call.getOperandList();
+    RelDataType elementType;
+    for (int i = 0; i < operands.size(); i++) {
+      if (i % 2 == 0) {
+        elementType = evenType;
+      } else {
+        elementType = oddType;
+      }
+      if (!operandTypes.get(i).equalsSansFieldNames(elementType)) {
+        call.setOperand(i, castTo(operands.get(i), elementType));
+      }
+    }
+  }
+
+  /**
+   * Creates a CAST operation to cast a given {@link SqlNode} to a specified {@link RelDataType}.
+   * This method uses the {@link SqlStdOperatorTable#CAST} operator to create a new {@link SqlCall}
+   * node representing a CAST operation. The original 'node' is cast to the desired 'type',
+   * preserving the nullability of the 'type'.
+   *
+   * @param node the {@link SqlNode} which is to be cast
+   * @param type the target {@link RelDataType} to which 'node' should be cast
+   * @return a new {@link SqlNode} representing the CAST operation
+   */
+  private static SqlNode castTo(SqlNode node, RelDataType type) {
+    return SqlStdOperatorTable.CAST.createCall(
+        SqlParserPos.ZERO,
+        node,
+        SqlTypeUtil.convertTypeToSpec(type).withNullable(type.isNullable()));
+  }
+
   //~ Inner Classes ----------------------------------------------------------
 
   /**

core/src/test/java/org/apache/calcite/test/JdbcTest.java

@@ -8144,10 +8144,9 @@ private void checkGetTimestamp(Connection con) throws SQLException {
    * ClassCastException retrieving from ARRAY that has mixed INTEGER and DECIMAL
    * elements</a>. */
   @Test void testIntAndBigDecimalInArray() {
-    // Result should be "EXPR$0=[1, 1.1]\n"; [CALCITE-4850] logged.
     CalciteAssert.that()
         .query("select array[1, 1.1]")
-        .returns("EXPR$0=[0E+1, 1.1]\n");
+        .returns("EXPR$0=[1, 1.1]\n");
   }
 
   /** Test case for

core/src/test/resources/sql/misc.iq

@@ -2179,12 +2179,12 @@ select array[1,null,2] as a from (values (1));
 
 values array['a',null,'bcd'],
   array['efgh'];
-+----------------+
-| EXPR$0         |
-+----------------+
-| [a, null, bcd] |
-| [efgh]         |
-+----------------+
++------------------+
+| EXPR$0           |
++------------------+
+| [a  , null, bcd] |
+| [efgh]           |
++------------------+
 (2 rows)
 
 !ok