Merge object children fields when resolved to same keys

kgraphql/src/main/kotlin/com/apurebase/kgraphql/schema/execution/ParallelRequestExecutor.kt

@@ -177,7 +177,7 @@ class ParallelRequestExecutor(val schema: DefaultSchema) : RequestExecutor {
                 is Execution.Fragment -> objectNode.setAll<JsonNode>(handleFragment(ctx, value, child))
                 else -> {
                     val (key, jsonNode) = handleProperty(ctx, value, child, type, node.children.size)
-                    objectNode.set(key, jsonNode)
+                    objectNode.merge(key, jsonNode)
                 }
             }
         }

kgraphql/src/test/kotlin/com/apurebase/kgraphql/integration/github/GitHubIssue197.kt

@@ -0,0 +1,118 @@
+package com.apurebase.kgraphql.integration.github
+
+import com.apurebase.kgraphql.defaultSchema
+import com.apurebase.kgraphql.deserialize
+import org.hamcrest.CoreMatchers
+import org.hamcrest.CoreMatchers.equalTo
+import org.hamcrest.MatcherAssert
+import org.hamcrest.MatcherAssert.assertThat
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.fail
+
+class GitHubIssue197 {
+
+    data class Outer(val inner1: Inner, val inner2: Inner)
+    data class Inner(val name: String)
+
+    private val testedSchema = defaultSchema {
+        query("outer") {
+            resolver { ->
+                Outer(Inner("test1"), Inner("test2"))
+            }
+        }
+        type<Inner> {
+            property("testProperty1") {
+                resolver { "${it.name}.testProperty1" }
+            }
+            property("testProperty2") {
+                resolver { "${it.name}.testProperty2" }
+            }
+        }
+    }
+
+    @Test
+    fun `executor should merge fragment declaration and field declaration`() {
+        val response = testedSchema.executeBlocking(//language=graphql
+            """
+            { 
+                outer { 
+                    ...TestFragment
+                    inner1 { testProperty1 } 
+                    inner2 { testProperty2 } 
+                } 
+            } 
+            fragment TestFragment on Outer {
+                inner1 { name, testProperty2 }
+                inner2 { name, testProperty1 }
+            }
+        """.trimIndent()
+        ).also(::println)
+
+        val deserialized = deserialize(response)
+        assertThat(
+            deserialized, equalTo(
+                mapOf(
+                    "data" to mapOf(
+                        "outer" to mapOf(
+                            "inner1" to mapOf(
+                                "name" to "test1",
+                                "testProperty2" to "test1.testProperty2",
+                                "testProperty1" to "test1.testProperty1",
+                            ),
+                            "inner2" to mapOf(
+                                "name" to "test2",
+                                "testProperty1" to "test2.testProperty1",
+                                "testProperty2" to "test2.testProperty2",
+                            ),
+                        )
+                    )
+                )
+            )
+        )
+    }
+
+    @Test
+    fun `executor should merge several fragment declarations and field declaration`() {
+        val response = testedSchema.executeBlocking(//language=graphql
+            """
+            { 
+                outer { 
+                    ...TestFragment1
+                    ...TestFragment2
+                    inner2 {
+                        testProperty2
+                    }
+                } 
+            } 
+            fragment TestFragment1 on Outer {
+                inner1 { name, testProperty2 }
+            }
+            fragment TestFragment2 on Outer {
+                inner2 { name, testProperty1 }
+            }
+        """.trimIndent()
+        ).also(::println)
+
+        val deserialized = deserialize(response)
+        assertThat(
+            deserialized, equalTo(
+                mapOf(
+                    "data" to mapOf(
+                        "outer" to mapOf(
+                            "inner1" to mapOf(
+                                "name" to "test1",
+                                "testProperty2" to "test1.testProperty2",
+                            ),
+                            "inner2" to mapOf(
+                                "name" to "test2",
+                                "testProperty1" to "test2.testProperty1",
+                                "testProperty2" to "test2.testProperty2",
+                            ),
+                        )
+                    )
+                )
+            )
+        )
+    }
+
+}