[Fix-18074][Task-Plugin] Announce varPool as IN parameter instead of directly putting OUT-direction varPool into params map

Author: leocook

dolphinscheduler-service/src/main/java/org/apache/dolphinscheduler/service/expand/CuringParamsServiceImpl.java

@@ -212,8 +212,13 @@ public Map<String, Property> paramParsingPreparation(@NonNull TaskInstance taskI
                     // Existing IN parameter: override its value
                     targetParam.setValue(varPool.getValue());
                 } else if (targetParam == null) {
-                    // Parameter not in map: inject it for placeholder resolution
-                    prepareParamsMap.put(varPool.getProp(), varPool);
+                    // Parameter not in map: announce as IN parameter from varPool for placeholder resolution
+                    Property newParam = new Property();
+                    newParam.setProp(varPool.getProp());
+                    newParam.setValue(varPool.getValue());
+                    newParam.setType(varPool.getType());
+                    newParam.setDirect(Direct.IN);
+                    prepareParamsMap.put(varPool.getProp(), newParam);
                 }
             }
         }

dolphinscheduler-service/src/test/java/org/apache/dolphinscheduler/service/expand/CuringParamsServiceImplTest.java

@@ -606,9 +606,11 @@ public void testParamParsingPreparation_varPoolInjectionWhenParamNameNotInLocalP
 
         Assertions.assertNotNull(propertyMap);
 
-        // Assert: p1 should be injected from varPool
+        // Assert: p1 should be injected from varPool and announced as IN direction
         Assertions.assertTrue(propertyMap.containsKey("p1"), "p1 should be injected from varPool");
         Assertions.assertEquals("111", propertyMap.get("p1").getValue());
+        Assertions.assertEquals(Direct.IN, propertyMap.get("p1").getDirect(),
+                "injected varPool param should be announced as IN direction");
 
         // Assert: p2 should exist and its value should be resolved from ${p1} to 111
         Assertions.assertTrue(propertyMap.containsKey("p2"));