From 61e95e5cbf550d446a0bc2e656a603d5bce19563 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Osadnik?= <osdnk@fb.com>
Date: Tue, 2 Jul 2019 02:59:04 -0700
Subject: [PATCH] Force WithDefault not to be an optional value

Summary:
`WithDefault` appears not to be required to be prefixed with `?` because it's option value per se.

Fixed tests, removed `?` where needed, updated snapshots and review them. Added mechanism fro throwing error when `?WithDefault` found. Add tests for it.

Reviewed By: rubennorte

Differential Revision: D16048463

fbshipit-source-id: f55ed7454aacf0b8c42944a9b5c1037ad1b360fe
---
 .../ActivityIndicatorViewNativeComponent.js   |  6 +--
 .../AndroidDialogPickerNativeComponent.js     |  4 +-
 .../AndroidDropdownPickerNativeComponent.js   |  4 +-
 .../ProgressBarAndroidNativeComponent.js      |  4 +-
 .../RCTProgressViewNativeComponent.js         |  4 +-
 ...ndroidSwipeRefreshLayoutNativeComponent.js |  8 ++--
 .../PullToRefreshViewNativeComponent.js       |  2 +-
 .../RCTSegmentedControlNativeComponent.js     |  6 +--
 .../Slider/SliderNativeComponent.js           | 14 +++----
 .../Switch/SwitchNativeComponent.js           |  4 +-
 .../UnimplementedNativeViewNativeComponent.js |  2 +-
 .../Modal/RCTModalHostViewNativeComponent.js  | 16 ++++----
 Libraries/Types/CodegenTypes.js               |  2 +-
 .../__test_fixtures__/fixtures.js             |  2 +-
 .../__snapshots__/index-test.js.snap          |  2 +-
 .../flow/__test_fixtures__/failures.js        | 31 ++++++++++++++
 .../flow/__test_fixtures__/fixtures.js        | 40 +++++++++----------
 .../__snapshots__/parser-test.js.snap         | 37 +----------------
 .../src/parsers/flow/props.js                 | 23 ++++++++---
 19 files changed, 110 insertions(+), 101 deletions(-)

diff --git a/Libraries/Components/ActivityIndicator/ActivityIndicatorViewNativeComponent.js b/Libraries/Components/ActivityIndicator/ActivityIndicatorViewNativeComponent.js
index 9cdb6f027e4..47c8fa1692a 100644
--- a/Libraries/Components/ActivityIndicator/ActivityIndicatorViewNativeComponent.js
+++ b/Libraries/Components/ActivityIndicator/ActivityIndicatorViewNativeComponent.js
@@ -25,14 +25,14 @@ type NativeProps = $ReadOnly<{|
    *
    * See http://facebook.github.io/react-native/docs/activityindicator.html#hideswhenstopped
    */
-  hidesWhenStopped?: ?WithDefault<boolean, false>,
+  hidesWhenStopped?: WithDefault<boolean, false>,
 
   /**
    * Whether to show the indicator (true, the default) or hide it (false).
    *
    * See http://facebook.github.io/react-native/docs/activityindicator.html#animating
    */
-  animating?: ?WithDefault<boolean, false>,
+  animating?: WithDefault<boolean, false>,
 
   /**
    * The foreground color of the spinner (default is gray).
@@ -47,7 +47,7 @@ type NativeProps = $ReadOnly<{|
    *
    * See http://facebook.github.io/react-native/docs/activityindicator.html#size
    */
-  size?: ?WithDefault<'small' | 'large', 'small'>,
+  size?: WithDefault<'small' | 'large', 'small'>,
 |}>;
 
 export default codegenNativeComponent<NativeProps>('ActivityIndicatorView', {
diff --git a/Libraries/Components/Picker/AndroidDialogPickerNativeComponent.js b/Libraries/Components/Picker/AndroidDialogPickerNativeComponent.js
index 77444816ef3..dd5f5a10912 100644
--- a/Libraries/Components/Picker/AndroidDialogPickerNativeComponent.js
+++ b/Libraries/Components/Picker/AndroidDialogPickerNativeComponent.js
@@ -37,9 +37,9 @@ type NativeProps = $ReadOnly<{|
 
   // Props
   color?: ?ColorValue,
-  enabled?: ?WithDefault<boolean, true>,
+  enabled?: WithDefault<boolean, true>,
   items: $ReadOnlyArray<PickerItem>,
-  prompt?: ?WithDefault<string, ''>,
+  prompt?: WithDefault<string, ''>,
   selected: Int32,
 
   // Events
diff --git a/Libraries/Components/Picker/AndroidDropdownPickerNativeComponent.js b/Libraries/Components/Picker/AndroidDropdownPickerNativeComponent.js
index 2b0e1773ef2..8f3976b4a66 100644
--- a/Libraries/Components/Picker/AndroidDropdownPickerNativeComponent.js
+++ b/Libraries/Components/Picker/AndroidDropdownPickerNativeComponent.js
@@ -37,9 +37,9 @@ type NativeProps = $ReadOnly<{|
 
   // Props
   color?: ?ColorValue,
-  enabled?: ?WithDefault<boolean, true>,
+  enabled?: WithDefault<boolean, true>,
   items: $ReadOnlyArray<PickerItem>,
-  prompt?: ?WithDefault<string, ''>,
+  prompt?: WithDefault<string, ''>,
   selected: Int32,
 
   // Events
diff --git a/Libraries/Components/ProgressBarAndroid/ProgressBarAndroidNativeComponent.js b/Libraries/Components/ProgressBarAndroid/ProgressBarAndroidNativeComponent.js
index fffa7c3f2c6..47af65b9f13 100644
--- a/Libraries/Components/ProgressBarAndroid/ProgressBarAndroidNativeComponent.js
+++ b/Libraries/Components/ProgressBarAndroid/ProgressBarAndroidNativeComponent.js
@@ -24,9 +24,9 @@ type NativeProps = $ReadOnly<{|
   typeAttr?: string,
   indeterminate: boolean,
   progress?: WithDefault<Float, 0>,
-  animating?: ?WithDefault<boolean, true>,
+  animating?: WithDefault<boolean, true>,
   color?: ?ColorValue,
-  testID?: ?WithDefault<string, ''>,
+  testID?: WithDefault<string, ''>,
 |}>;
 
 export default codegenNativeComponent<NativeProps>('AndroidProgressBar');
diff --git a/Libraries/Components/ProgressViewIOS/RCTProgressViewNativeComponent.js b/Libraries/Components/ProgressViewIOS/RCTProgressViewNativeComponent.js
index 3a9e4b138e0..ba8427354cb 100644
--- a/Libraries/Components/ProgressViewIOS/RCTProgressViewNativeComponent.js
+++ b/Libraries/Components/ProgressViewIOS/RCTProgressViewNativeComponent.js
@@ -21,8 +21,8 @@ type NativeProps = $ReadOnly<{|
   ...ViewProps,
 
   // Props
-  progressViewStyle?: ?WithDefault<'default' | 'bar', 'default'>,
-  progress?: ?WithDefault<Float, 0>,
+  progressViewStyle?: WithDefault<'default' | 'bar', 'default'>,
+  progress?: WithDefault<Float, 0>,
   progressTintColor?: ?ColorValue,
   trackTintColor?: ?ColorValue,
   progressImage?: ?ImageSource,
diff --git a/Libraries/Components/RefreshControl/AndroidSwipeRefreshLayoutNativeComponent.js b/Libraries/Components/RefreshControl/AndroidSwipeRefreshLayoutNativeComponent.js
index 9e8f0ea583b..4109dae7f82 100644
--- a/Libraries/Components/RefreshControl/AndroidSwipeRefreshLayoutNativeComponent.js
+++ b/Libraries/Components/RefreshControl/AndroidSwipeRefreshLayoutNativeComponent.js
@@ -27,7 +27,7 @@ type NativeProps = $ReadOnly<{|
   /**
    * Whether the pull to refresh functionality is enabled.
    */
-  enabled?: ?WithDefault<boolean, false>,
+  enabled?: WithDefault<boolean, false>,
   /**
    * The colors (at least one) that will be used to draw the refresh indicator.
    */
@@ -45,13 +45,13 @@ type NativeProps = $ReadOnly<{|
    * Also, 1 isn't actually a safe default. We are able to set this here
    * because native code isn't currently consuming the generated artifact.
    * This will end up being
-   * size?: ?WithDefault<'default' | 'large', 'default'>,
+   * size?: WithDefault<'default' | 'large', 'default'>,
    */
-  size?: ?WithDefault<Int32, 1>,
+  size?: WithDefault<Int32, 1>,
   /**
    * Progress view top offset
    */
-  progressViewOffset?: ?WithDefault<Float, 0>,
+  progressViewOffset?: WithDefault<Float, 0>,
 
   /**
    * Called when the view starts refreshing.
diff --git a/Libraries/Components/RefreshControl/PullToRefreshViewNativeComponent.js b/Libraries/Components/RefreshControl/PullToRefreshViewNativeComponent.js
index a38f28b4695..87851403fa2 100644
--- a/Libraries/Components/RefreshControl/PullToRefreshViewNativeComponent.js
+++ b/Libraries/Components/RefreshControl/PullToRefreshViewNativeComponent.js
@@ -30,7 +30,7 @@ type NativeProps = $ReadOnly<{|
   /**
    * The title displayed under the refresh indicator.
    */
-  title?: ?WithDefault<string, null>,
+  title?: WithDefault<string, null>,
 
   /**
    * Called when the view starts refreshing.
diff --git a/Libraries/Components/SegmentedControlIOS/RCTSegmentedControlNativeComponent.js b/Libraries/Components/SegmentedControlIOS/RCTSegmentedControlNativeComponent.js
index 9105deddd2a..b21f7148824 100644
--- a/Libraries/Components/SegmentedControlIOS/RCTSegmentedControlNativeComponent.js
+++ b/Libraries/Components/SegmentedControlIOS/RCTSegmentedControlNativeComponent.js
@@ -28,10 +28,10 @@ type NativeProps = $ReadOnly<{|
 
   // Props
   values?: $ReadOnlyArray<string>,
-  selectedIndex?: ?WithDefault<Int32, 0>,
-  enabled?: ?WithDefault<boolean, true>,
+  selectedIndex?: WithDefault<Int32, 0>,
+  enabled?: WithDefault<boolean, true>,
   tintColor?: ?ColorValue,
-  momentary?: ?WithDefault<boolean, false>,
+  momentary?: WithDefault<boolean, false>,
 
   // Events
   onChange?: ?BubblingEventHandler<OnChangeEvent>,
diff --git a/Libraries/Components/Slider/SliderNativeComponent.js b/Libraries/Components/Slider/SliderNativeComponent.js
index 9b809e1ca65..f6475bbd882 100644
--- a/Libraries/Components/Slider/SliderNativeComponent.js
+++ b/Libraries/Components/Slider/SliderNativeComponent.js
@@ -32,20 +32,20 @@ type NativeProps = $ReadOnly<{|
   ...ViewProps,
 
   // Props
-  disabled?: ?WithDefault<boolean, false>,
-  enabled?: ?WithDefault<boolean, false>,
+  disabled?: WithDefault<boolean, false>,
+  enabled?: WithDefault<boolean, false>,
   maximumTrackImage?: ?ImageSource,
   maximumTrackTintColor?: ?ColorValue,
-  maximumValue?: ?WithDefault<Float, 1>,
+  maximumValue?: WithDefault<Float, 1>,
   minimumTrackImage?: ?ImageSource,
   minimumTrackTintColor?: ?ColorValue,
-  minimumValue?: ?WithDefault<Float, 0>,
-  step?: ?WithDefault<Float, 0>,
-  testID?: ?WithDefault<string, ''>,
+  minimumValue?: WithDefault<Float, 0>,
+  step?: WithDefault<Float, 0>,
+  testID?: WithDefault<string, ''>,
   thumbImage?: ?ImageSource,
   thumbTintColor?: ?ColorValue,
   trackImage?: ?ImageSource,
-  value: ?WithDefault<Float, 0>,
+  value: WithDefault<Float, 0>,
 
   // Events
   onChange?: ?BubblingEventHandler<Event>,
diff --git a/Libraries/Components/Switch/SwitchNativeComponent.js b/Libraries/Components/Switch/SwitchNativeComponent.js
index ea223bbde5e..1315d2addbd 100644
--- a/Libraries/Components/Switch/SwitchNativeComponent.js
+++ b/Libraries/Components/Switch/SwitchNativeComponent.js
@@ -24,8 +24,8 @@ type NativeProps = $ReadOnly<{|
   ...ViewProps,
 
   // Props
-  disabled?: ?WithDefault<boolean, false>,
-  value?: ?WithDefault<boolean, false>,
+  disabled?: WithDefault<boolean, false>,
+  value?: WithDefault<boolean, false>,
   tintColor?: ?ColorValue,
   onTintColor?: ?ColorValue,
   thumbTintColor?: ?ColorValue,
diff --git a/Libraries/Components/UnimplementedViews/UnimplementedNativeViewNativeComponent.js b/Libraries/Components/UnimplementedViews/UnimplementedNativeViewNativeComponent.js
index 353a3102d96..ed0622ab428 100644
--- a/Libraries/Components/UnimplementedViews/UnimplementedNativeViewNativeComponent.js
+++ b/Libraries/Components/UnimplementedViews/UnimplementedNativeViewNativeComponent.js
@@ -17,7 +17,7 @@ import codegenNativeComponent from '../../Utilities/codegenNativeComponent';
 
 type NativeProps = $ReadOnly<{|
   ...ViewProps,
-  name?: ?WithDefault<string, ''>,
+  name?: WithDefault<string, ''>,
 |}>;
 
 // NOTE: This compoenent is not implemented in paper
diff --git a/Libraries/Modal/RCTModalHostViewNativeComponent.js b/Libraries/Modal/RCTModalHostViewNativeComponent.js
index 1e305442d35..b8e8f06e9b3 100644
--- a/Libraries/Modal/RCTModalHostViewNativeComponent.js
+++ b/Libraries/Modal/RCTModalHostViewNativeComponent.js
@@ -32,14 +32,14 @@ type NativeProps = $ReadOnly<{|
    *
    * See https://facebook.github.io/react-native/docs/modal.html#animationtype
    */
-  animationType?: ?WithDefault<'none' | 'slide' | 'fade', 'none'>,
+  animationType?: WithDefault<'none' | 'slide' | 'fade', 'none'>,
 
   /**
    * The `presentationStyle` prop controls how the modal appears.
    *
    * See https://facebook.github.io/react-native/docs/modal.html#presentationstyle
    */
-  presentationStyle?: ?WithDefault<
+  presentationStyle?: WithDefault<
     'fullScreen' | 'pageSheet' | 'formSheet' | 'overFullScreen',
     'fullScreen',
   >,
@@ -50,7 +50,7 @@ type NativeProps = $ReadOnly<{|
    *
    * See https://facebook.github.io/react-native/docs/modal.html#transparent
    */
-  transparent?: ?WithDefault<boolean, false>,
+  transparent?: WithDefault<boolean, false>,
 
   /**
    * The `hardwareAccelerated` prop controls whether to force hardware
@@ -58,14 +58,14 @@ type NativeProps = $ReadOnly<{|
    *
    * See https://facebook.github.io/react-native/docs/modal.html#hardwareaccelerated
    */
-  hardwareAccelerated?: ?WithDefault<boolean, false>,
+  hardwareAccelerated?: WithDefault<boolean, false>,
 
   /**
    * The `visible` prop determines whether your modal is visible.
    *
    * See https://facebook.github.io/react-native/docs/modal.html#visible
    */
-  visible?: ?WithDefault<boolean, false>,
+  visible?: WithDefault<boolean, false>,
 
   /**
    * The `onRequestClose` callback is called when the user taps the hardware
@@ -96,14 +96,14 @@ type NativeProps = $ReadOnly<{|
   /**
    * Deprecated. Use the `animationType` prop instead.
    */
-  animated?: ?WithDefault<boolean, false>,
+  animated?: WithDefault<boolean, false>,
 
   /**
    * The `supportedOrientations` prop allows the modal to be rotated to any of the specified orientations.
    *
    * See https://facebook.github.io/react-native/docs/modal.html#supportedorientations
    */
-  supportedOrientations?: ?WithDefault<
+  supportedOrientations?: WithDefault<
     $ReadOnlyArray<
       | 'portrait'
       | 'portrait-upside-down'
@@ -124,7 +124,7 @@ type NativeProps = $ReadOnly<{|
   /**
    * The `identifier` is the unique number for identifying Modal components.
    */
-  identifier?: ?WithDefault<Int32, 0>,
+  identifier?: WithDefault<Int32, 0>,
 |}>;
 
 export default codegenNativeComponent<NativeProps>('ModalHostView', {
diff --git a/Libraries/Types/CodegenTypes.js b/Libraries/Types/CodegenTypes.js
index 8a385d850f8..0ef355ddbd6 100644
--- a/Libraries/Types/CodegenTypes.js
+++ b/Libraries/Types/CodegenTypes.js
@@ -36,4 +36,4 @@ type DefaultTypes = number | boolean | string | $ReadOnlyArray<string>;
 //  but that is currently not supported in the codegen since we require a default
 //
 // eslint-disable-next-line no-unused-vars
-export type WithDefault<Type: DefaultTypes, Value: ?Type | string> = Type;
+export type WithDefault<Type: DefaultTypes, Value: ?Type | string> = ?Type;
diff --git a/packages/babel-plugin-inline-view-configs/__test_fixtures__/fixtures.js b/packages/babel-plugin-inline-view-configs/__test_fixtures__/fixtures.js
index d4ad955d4d0..c40d4ed27f7 100644
--- a/packages/babel-plugin-inline-view-configs/__test_fixtures__/fixtures.js
+++ b/packages/babel-plugin-inline-view-configs/__test_fixtures__/fixtures.js
@@ -39,7 +39,7 @@ type ModuleProps = $ReadOnly<{|
   ...ViewProps,
 
   // Props
-  boolean_default_true_optional_both?: ?WithDefault<boolean, true>,
+  boolean_default_true_optional_both?: WithDefault<boolean, true>,
 
   // Events
   onDirectEventDefinedInlineNull: DirectEventHandler<null>,
diff --git a/packages/babel-plugin-inline-view-configs/__tests__/__snapshots__/index-test.js.snap b/packages/babel-plugin-inline-view-configs/__tests__/__snapshots__/index-test.js.snap
index 1e29afabb80..9d203135ccd 100644
--- a/packages/babel-plugin-inline-view-configs/__tests__/__snapshots__/index-test.js.snap
+++ b/packages/babel-plugin-inline-view-configs/__tests__/__snapshots__/index-test.js.snap
@@ -14,7 +14,7 @@ interface NativeCommands {
 }
 type ModuleProps = $ReadOnly<{| ...ViewProps,
   // Props
-  boolean_default_true_optional_both?: ?WithDefault<boolean, true>,
+  boolean_default_true_optional_both?: WithDefault<boolean, true>,
   // Events
   onDirectEventDefinedInlineNull: DirectEventHandler<null>,
   onBubblingEventDefinedInlineNull: BubblingEventHandler<null>,
diff --git a/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/failures.js b/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/failures.js
index 19907602b12..88681a062d5 100644
--- a/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/failures.js
+++ b/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/failures.js
@@ -120,6 +120,36 @@ export type ModuleProps = $ReadOnly<{|
 
 export const Commands = codegenNativeCommands<NativeCommands>();
 
+export default codegenNativeComponent<ModuleProps>('Module');
+`;
+const NULLABLE_WITH_DEFAULT = `
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @flow
+ */
+
+'use strict';
+
+const codegenNativeComponent = require('codegenNativeComponent');
+
+import type {
+  WithDefault,
+  Float,
+} from 'CodegenTypes';
+
+import type {ViewProps} from 'ViewPropTypes';
+
+
+export type ModuleProps = $ReadOnly<{|
+  ...ViewProps,
+  nullable_with_default: ?WithDefault<Float, 1.0>,
+|}>;
+
 export default codegenNativeComponent<ModuleProps>('Module');
 `;
 
@@ -127,4 +157,5 @@ module.exports = {
   COMMANDS_DEFINED_INLINE,
   COMMANDS_DEFINED_MULTIPLE_TIMES,
   COMMANDS_DEFINED_WITHOUT_REF,
+  NULLABLE_WITH_DEFAULT,
 };
diff --git a/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/fixtures.js b/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/fixtures.js
index de6e81d7d7b..617f7039fdc 100644
--- a/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/fixtures.js
+++ b/packages/react-native-codegen/src/parsers/flow/__test_fixtures__/fixtures.js
@@ -89,7 +89,7 @@ type ModuleProps = $ReadOnly<{|
   ...ViewProps,
 
   // Props
-  boolean_default_true_optional_both?: ?WithDefault<boolean, true>,
+  boolean_default_true_optional_both?: WithDefault<boolean, true>,
 
   // Events
   onDirectEventDefinedInlineNull: DirectEventHandler<null>,
@@ -160,48 +160,47 @@ type ModuleProps = $ReadOnly<{|
   // Boolean props
   boolean_required: boolean,
   boolean_optional_key?: WithDefault<boolean, true>,
-  boolean_optional_value: ?WithDefault<boolean, true>,
-  boolean_optional_both?: ?WithDefault<boolean, true>,
+  boolean_optional_value: WithDefault<boolean, true>,
+  boolean_optional_both?: WithDefault<boolean, true>,
 
   // String props
   string_required: string,
   string_optional_key?: WithDefault<string, ''>,
-  string_optional_value: ?WithDefault<string, ''>,
-  string_optional_both?: ?WithDefault<string, ''>,
+  string_optional_value: WithDefault<string, ''>,
+  string_optional_both?: WithDefault<string, ''>,
 
   // String props, null default
   string_null_optional_key?: WithDefault<string, null>,
-  string_null_optional_value: ?WithDefault<string, null>,
-  string_null_optional_both?: ?WithDefault<string, null>,
+  string_null_optional_value: WithDefault<string, null>,
+  string_null_optional_both?: WithDefault<string, null>,
 
   // Stringish props
   stringish_required: Stringish,
   stringish_optional_key?: WithDefault<Stringish, ''>,
-  stringish_optional_value: ?WithDefault<Stringish, ''>,
-  stringish_optional_both?: ?WithDefault<Stringish, ''>,
+  stringish_optional_value: WithDefault<Stringish, ''>,
+  stringish_optional_both?: WithDefault<Stringish, ''>,
 
   // Stringish props, null default
   stringish_null_optional_key?: WithDefault<Stringish, null>,
-  stringish_null_optional_value: ?WithDefault<Stringish, null>,
-  stringish_null_optional_both?: ?WithDefault<Stringish, null>,
+  stringish_null_optional_value: WithDefault<Stringish, null>,
+  stringish_null_optional_both?: WithDefault<Stringish, null>,
 
   // Float props
   float_required: Float,
   float_optional_key?: WithDefault<Float, 1.1>,
-  float_optional_value: ?WithDefault<Float, 1.1>,
-  float_optional_both?: ?WithDefault<Float, 1.1>,
+  float_optional_value: WithDefault<Float, 1.1>,
+  float_optional_both?: WithDefault<Float, 1.1>,
 
   // Int32 props
   int32_required: Int32,
   int32_optional_key?: WithDefault<Int32, 1>,
-  int32_optional_value: ?WithDefault<Int32, 1>,
-  int32_optional_both?: ?WithDefault<Int32, 1>,
+  int32_optional_value: WithDefault<Int32, 1>,
+  int32_optional_both?: WithDefault<Int32, 1>,
 
   // String enum props
-  enum_required: WithDefault<('small' | 'large'), 'small'>,
   enum_optional_key?: WithDefault<('small' | 'large'), 'small'>,
-  enum_optional_value: ?WithDefault<('small' | 'large'), 'small'>,
-  enum_optional_both?: ?WithDefault<('small' | 'large'), 'small'>,
+  enum_optional_value: WithDefault<('small' | 'large'), 'small'>,
+  enum_optional_both?: WithDefault<('small' | 'large'), 'small'>,
 
   // ImageSource props
   image_required: ImageSource,
@@ -284,10 +283,9 @@ type ModuleProps = $ReadOnly<{|
   array_int32_optional_both?: ?$ReadOnlyArray<Int32>,
 
   // String enum props
-  array_enum_required: WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
   array_enum_optional_key?: WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
-  array_enum_optional_value: ?WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
-  array_enum_optional_both?: ?WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
+  array_enum_optional_value: WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
+  array_enum_optional_both?: WithDefault<$ReadOnlyArray<('small' | 'large')>, 'small'>,
 
   // ImageSource props
   array_image_required: $ReadOnlyArray<ImageSource>,
diff --git a/packages/react-native-codegen/src/parsers/flow/__tests__/__snapshots__/parser-test.js.snap b/packages/react-native-codegen/src/parsers/flow/__tests__/__snapshots__/parser-test.js.snap
index db03605d833..2171259177a 100644
--- a/packages/react-native-codegen/src/parsers/flow/__tests__/__snapshots__/parser-test.js.snap
+++ b/packages/react-native-codegen/src/parsers/flow/__tests__/__snapshots__/parser-test.js.snap
@@ -6,6 +6,8 @@ exports[`RN Codegen Flow Parser Fails with error message COMMANDS_DEFINED_MULTIP
 
 exports[`RN Codegen Flow Parser Fails with error message COMMANDS_DEFINED_WITHOUT_REF 1`] = `"The first argument of method hotspotUpdate must be of type React.Ref<>"`;
 
+exports[`RN Codegen Flow Parser Fails with error message NULLABLE_WITH_DEFAULT 1`] = `"WithDefault<> is optional and does not need to be marked as optional. Please remove the ? annotation in front of it."`;
+
 exports[`RN Codegen Flow Parser can generate fixture ALL_PROP_TYPES_NO_EVENTS 1`] = `
 Object {
   "modules": Object {
@@ -229,22 +231,6 @@ Object {
                 "type": "Int32TypeAnnotation",
               },
             },
-            Object {
-              "name": "enum_required",
-              "optional": false,
-              "typeAnnotation": Object {
-                "default": "small",
-                "options": Array [
-                  Object {
-                    "name": "small",
-                  },
-                  Object {
-                    "name": "large",
-                  },
-                ],
-                "type": "StringEnumTypeAnnotation",
-              },
-            },
             Object {
               "name": "enum_optional_key",
               "optional": true,
@@ -608,25 +594,6 @@ Object {
                 "type": "ArrayTypeAnnotation",
               },
             },
-            Object {
-              "name": "array_enum_required",
-              "optional": false,
-              "typeAnnotation": Object {
-                "elementType": Object {
-                  "default": "small",
-                  "options": Array [
-                    Object {
-                      "name": "small",
-                    },
-                    Object {
-                      "name": "large",
-                    },
-                  ],
-                  "type": "StringEnumTypeAnnotation",
-                },
-                "type": "ArrayTypeAnnotation",
-              },
-            },
             Object {
               "name": "array_enum_optional_key",
               "optional": true,
diff --git a/packages/react-native-codegen/src/parsers/flow/props.js b/packages/react-native-codegen/src/parsers/flow/props.js
index b07c444777a..9d7907ddf8d 100644
--- a/packages/react-native-codegen/src/parsers/flow/props.js
+++ b/packages/react-native-codegen/src/parsers/flow/props.js
@@ -176,13 +176,26 @@ function getTypeAnnotation(name, typeAnnotation, defaultValue) {
 
 function buildPropSchema(property): ?PropTypeShape {
   const name = property.key.name;
-  const optional =
-    property.value.type === 'NullableTypeAnnotation' || property.optional;
 
+  const {value} = property;
   let typeAnnotation =
-    property.value.type === 'NullableTypeAnnotation'
-      ? property.value.typeAnnotation
-      : property.value;
+    value.type === 'NullableTypeAnnotation' ? value.typeAnnotation : value;
+
+  const optional =
+    value.type === 'NullableTypeAnnotation' ||
+    property.optional ||
+    (value.type === 'GenericTypeAnnotation' &&
+      typeAnnotation.id.name === 'WithDefault');
+
+  if (
+    value.type === 'NullableTypeAnnotation' &&
+    (typeAnnotation.type === 'GenericTypeAnnotation' &&
+      typeAnnotation.id.name === 'WithDefault')
+  ) {
+    throw new Error(
+      'WithDefault<> is optional and does not need to be marked as optional. Please remove the ? annotation in front of it.',
+    );
+  }
 
   let type = typeAnnotation.type;
   if (