Disable init when using field merging

Tests/ApolloCodegenTests/CodeGeneration/Templates/FragmentTemplateTests.swift

@@ -621,6 +621,50 @@ class FragmentTemplateTests: XCTestCase {
     expect(actual).to(equalLineByLine(expected, atLine: 20, ignoringExtraLines: true))
   }
 
+  func test__render_givenOperationSelectionSet_initializerConfig_all_fieldMergingConfig_notAll_doesNotRenderInitializer() async throws {
+    let tests: [ApolloCodegenConfiguration.FieldMerging] = [
+      .none,
+      .ancestors,
+      .namedFragments,
+      .siblings,
+      [.ancestors, .namedFragments],
+      [.siblings, .ancestors],
+      [.siblings, .namedFragments]
+    ]
+
+    for test in tests {
+      // given
+      schemaSDL = """
+      type Query {
+        allAnimals: [Animal!]
+      }
+
+      type Animal {
+        species: String!
+      }
+      """
+
+      document = """
+      fragment TestFragment on Animal {
+        species
+      }
+      """
+
+      // when
+      try await buildSubjectAndFragment(config: .mock(
+        options: .init(
+          selectionSetInitializers: [.all],
+          fieldMerging: test
+        )
+      ))
+
+      let actual = renderSubject()
+
+      // then
+      expect(actual).to(equalLineByLine("}", atLine: 16, ignoringExtraLines: true))
+    }
+  }
+
   // MARK: Local Cache Mutation Tests
   func test__render__givenFragment__asLocalCacheMutation_generatesFragmentDeclarationDefinitionAsMutableSelectionSetAndBoilerplate() async throws {
     // given

Tests/ApolloCodegenTests/CodeGeneration/Templates/OperationDefinitionTemplateTests.swift

@@ -636,6 +636,54 @@ class OperationDefinitionTemplateTests: XCTestCase {
     expect(actual).to(equalLineByLine("    }", atLine: 35, ignoringExtraLines: true))
   }
 
+  func test__render_givenOperationSelectionSet_initializerConfig_all_fieldMergingConfig_notAll_doesNotRenderInitializer() async throws {
+    let tests: [ApolloCodegenConfiguration.FieldMerging] = [
+      .none,
+      .ancestors,
+      .namedFragments,
+      .siblings,
+      [.ancestors, .namedFragments],
+      [.siblings, .ancestors],
+      [.siblings, .namedFragments]
+    ]
+
+    for test in tests {
+      // given
+      schemaSDL = """
+      type Query {
+        allAnimals: [Animal!]
+      }
+
+      type Animal {
+        species: String!
+      }
+      """
+
+      document = """
+      query TestOperation {
+        allAnimals {
+          species
+        }
+      }
+      """
+
+      config = .mock(
+        options: .init(
+          selectionSetInitializers: [.all],
+          fieldMerging: test
+        )
+      )
+
+      // when
+      try await buildSubjectAndOperation()
+
+      let actual = renderSubject()
+
+      // then
+      expect(actual).to(equalLineByLine("    }", atLine: 35, ignoringExtraLines: true))
+    }
+  }
+
   // MARK: - Variables
 
   func test__generate__givenQueryWithScalarVariable_generatesQueryOperationWithVariable() async throws {

Tests/ApolloCodegenTests/CodeGeneration/Templates/SelectionSet/SelectionSetTemplate_FieldMerging_Tests.swift

@@ -543,7 +543,7 @@ class SelectionSetTemplate_FieldMerging_Tests: XCTestCase {
       allAnimals {
         predator {
           species
-        }        
+        }
         ... on Dog {
           species
         }
@@ -1218,82 +1218,4 @@ class SelectionSetTemplate_FieldMerging_Tests: XCTestCase {
     expect(actual).to(equalLineByLine(expected, atLine: 12, ignoringExtraLines: true))
   }
 
-  // MARK: - SelectionSetInitializers
-
-  func test__render_selectionSetInitializer__givenFieldMerging_none_withMergedSelections_rendersInitializerWithAllMergedSelections() async throws {
-    // given
-    schemaSDL = """
-    type Query {
-      allAnimals: [Animal!]
-    }
-
-    interface Animal {
-      species: String!
-      age: Int!
-    }
-
-    interface Pet implements Animal {
-      species: String!
-      age: Int!
-    }
-
-    type Dog implements Animal & Pet {
-      species: String!
-      age: Int!
-      bark: Boolean!
-    }
-    """
-
-    document = """
-    query TestOperation {
-      allAnimals {
-        age
-        ... on Pet {
-          species
-        }
-        ... on Dog {
-          bark
-        }
-      }
-    }
-    """
-
-    let expected =
-    """
-      public init(
-        bark: Bool,
-        age: Int,
-        species: String
-      ) {
-        self.init(_dataDict: DataDict(
-          data: [
-            "__typename": TestSchema.Objects.Dog.typename,
-            "bark": bark,
-            "age": age,
-            "species": species,
-          ],
-          fulfilledFragments: [
-            ObjectIdentifier(TestOperationQuery.Data.AllAnimal.self),
-            ObjectIdentifier(TestOperationQuery.Data.AllAnimal.AsDog.self),
-            ObjectIdentifier(TestOperationQuery.Data.AllAnimal.AsPet.self)
-          ]
-        ))
-      }
-    """
-
-    // when
-    try await buildSubjectAndOperation(
-      fieldMerging: .none,
-      selectionSetInitializers: true
-    )
-
-    let allAnimals_asDog = try XCTUnwrap(
-      operation[field: "query"]?[field: "allAnimals"]?[as: "Dog"]
-    )
-
-    let actual = subject.test_render(childEntity: allAnimals_asDog.computed)
-
-    // then
-    expect(actual).to(equalLineByLine(expected, atLine: 14, ignoringExtraLines: true))
-  }
 }

apollo-ios-codegen/Sources/ApolloCodegenLib/ApolloCodegenConfiguration.swift

@@ -1177,6 +1177,8 @@ extension ApolloCodegenConfiguration.OperationsFileOutput {
 extension ApolloCodegenConfiguration.OutputOptions {
   /// Determine whether the operations files are output to the schema types module.
   func shouldGenerateSelectionSetInitializers(for operation: IR.Operation) -> Bool {
+    guard fieldMerging == .all else { return false }
+
     switch operation.definition.isLocalCacheMutation {
     case true where selectionSetInitializers.contains(.localCacheMutations):
       return true
@@ -1191,6 +1193,8 @@ extension ApolloCodegenConfiguration.OutputOptions {
 
   /// Determine whether the operations files are output to the schema types module.
   func shouldGenerateSelectionSetInitializers(for fragment: IR.NamedFragment) -> Bool {
+    guard fieldMerging == .all else { return false }
+
     if selectionSetInitializers.contains(.namedFragments) { return true }
 
     if fragment.definition.isLocalCacheMutation &&