Fix BInvokableType record fields of effective types not inheriting readonly flag

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/util/TypeDefBuilderHelper.java

@@ -330,7 +330,7 @@ public static void populateStructureFieldsAndTypeInclusions(Types types, SymbolT
                 invokableSymbol.params = tsymbol.params == null ? null : new ArrayList<>(tsymbol.params);
                 invokableSymbol.restParam = tsymbol.restParam;
                 invokableSymbol.retType = tsymbol.returnType;
-                invokableSymbol.flags = tsymbol.flags;
+                invokableSymbol.flags = invokableSymbol.flags | tsymbol.flags;
             } else if (fieldType == symTable.semanticError) {
                 // Can only happen for records.
                 fieldSymbol = new BVarSymbol(origField.symbol.flags | flag | Flags.OPTIONAL,

tests/jballerina-unit-test/src/test/java/org/ballerinalang/test/record/ReadonlyRecordFieldTest.java

@@ -40,6 +40,15 @@ public void testReadonlyRecordFields(String testFunction) {
         BRunUtil.invoke(result, testFunction);
     }
 
+    @Test
+    public void testReadonlyInheritanceForInvokableTypeRecordField() {
+        BCompileUtil.compileAndCacheBala(
+                "test-src/record/cloned_record_field_flag_inheritance/imported_module_with_readonly_records");
+        CompileResult result = BCompileUtil.compile(
+                "test-src/record/cloned_record_field_flag_inheritance/module_with_field_access_for_readonly_record");
+        assertEquals(result.getErrorCount(), 0);
+    }
+
     @DataProvider(name = "readonlyRecordFieldTestFunctions")
     public Object[][] readonlyRecordFieldTestFunctions() {
         return new Object[][]{

tests/jballerina-unit-test/src/test/resources/test-src/record/cloned_record_field_flag_inheritance/imported_module_with_readonly_records/Ballerina.toml

@@ -0,0 +1,4 @@
+[package]
+org = "test_org"
+name = "ReadonlyRecord"
+version = "0.1.0"

tests/jballerina-unit-test/src/test/resources/test-src/record/cloned_record_field_flag_inheritance/imported_module_with_readonly_records/util.bal

@@ -0,0 +1,25 @@
+// Copyright (c) 2024, WSO2 LLC. (http://www.wso2.com).
+//
+// WSO2 LLC. licenses this file to you under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except
+// in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+public type InvokableTypeDef function (int) returns int;
+
+public type RecA record {|
+    readonly & InvokableTypeDef preProcessor?;
+|};
+
+public type RecB record {|
+    readonly RecA[] recArr;
+|};

tests/jballerina-unit-test/src/test/resources/test-src/record/cloned_record_field_flag_inheritance/module_with_field_access_for_readonly_record/Ballerina.toml

@@ -0,0 +1,10 @@
+[package]
+org = "test_org"
+name = "LocalPkgUsage"
+version = "0.1.0"
+
+[[dependency]]
+org = "test_org"
+name = "ReadonlyRecord"
+version = "0.1.0"
+repository="local"

tests/jballerina-unit-test/src/test/resources/test-src/record/cloned_record_field_flag_inheritance/module_with_field_access_for_readonly_record/main.bal

@@ -0,0 +1,25 @@
+// Copyright (c) 2024, WSO2 LLC. (http://www.wso2.com).
+//
+// WSO2 LLC. licenses this file to you under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except
+// in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+import test_org/ReadonlyRecord;
+
+ReadonlyRecord:RecB rec = {
+    recArr: []
+};
+
+public function main() {
+    ReadonlyRecord:RecA[] & readonly ops = rec.recArr;
+}