Fix ObjC structs with id properties

Summary:
## Problem
Suppose we have this NativeModule spec, that uses Object literals that contain a property called "id":

```
export interface Spec extends TurboModule {
  // Exported methods.
  +getConstants: () => {|
    id: string,
  |};

  +getObject: (arg: {id: Object}) => Object;
}
```

For both object literals, we'll generate C++ structs, backed by NSDictionaries. The method in each struct will be named "id_" to avoid a name clash with ObjC's `id` identifier. However, calling that id_ method should still access the "id" property in the corresponding NSDictionary.

## Expected Output
```
inline id<NSObject> JS::NativeSampleTurboModule::SpecGetObjectArg::id_() const
{
  id const p = _v[@"id"];
  return p;
}
inline JS::NativeSampleTurboModule::Constants::Builder::Builder(const Input i) : _factory(^{
  NSMutableDictionary *d = [NSMutableDictionary new];
  auto id_ = i.id_.get();
  d[@"id"] = id_;
  return d;
}) {}
```

## Actual Output
```
inline id<NSObject> JS::NativeSampleTurboModule::SpecGetObjectArg::id_() const
{
  id const p = _v[@"id_"]; // <-- HERE!
  return p;
}
inline JS::NativeSampleTurboModule::Constants::Builder::Builder(const Input i) : _factory(^{
  NSMutableDictionary *d = [NSMutableDictionary new];
  auto id_ = i.id_.get();
  d[@"id_"] = id_; // <-- HERE!
  return d;
}) {}
```

NOTE: This code was generated by running `jf get --version 119805822 && buck build //xplat/js:FBReactNativeSpec_Sample-flow-types-ios --show-output`

This diff fixes this mistake.

Changelog: [Internal]

Reviewed By: fkgozali

Differential Revision: D25907493

fbshipit-source-id: cb37cbf49db4f871b3f4046f7397a7b1b7df0357

packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeConstantsStruct.js

@@ -222,15 +222,15 @@ function serializeConstantsStruct(
     builderInputProps: struct.properties
       .map(property => {
         const {typeAnnotation, optional} = property;
-        const propName = getSafePropertyName(property);
+        const safePropName = getSafePropertyName(property);
         const objCType = toObjCType(hasteModuleName, typeAnnotation, optional);
 
         if (!optional) {
-          return `RCTRequired<${objCType}> ${propName};`;
+          return `RCTRequired<${objCType}> ${safePropName};`;
         }
 
         const space = ' '.repeat(objCType.endsWith('*') ? 0 : 1);
-        return `${objCType}${space}${propName};`;
+        return `${objCType}${space}${safePropName};`;
       })
       .join('\n          '),
   });
@@ -240,17 +240,17 @@ function serializeConstantsStruct(
     structName: struct.name,
     properties: struct.properties
       .map(property => {
-        const {typeAnnotation, optional} = property;
-        const propName = getSafePropertyName(property);
+        const {typeAnnotation, optional, name: propName} = property;
+        const safePropName = getSafePropertyName(property);
         const objCValue = toObjCValue(
           hasteModuleName,
           typeAnnotation,
-          propName,
+          safePropName,
           0,
           optional,
         );
 
-        let varDecl = `auto ${propName} = i.${propName}`;
+        let varDecl = `auto ${safePropName} = i.${safePropName}`;
         if (!optional) {
           varDecl += '.get()';
         }

packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/header/serializeRegularStruct.js

@@ -52,13 +52,15 @@ const MethodTemplate = ({
   hasteModuleName,
   structName,
   propertyName,
+  safePropertyName,
 }: $ReadOnly<{
   returnType: string,
   returnValue: string,
   hasteModuleName: string,
   structName: string,
   propertyName: string,
-}>) => `inline ${returnType}JS::${hasteModuleName}::${structName}::${propertyName}() const
+  safePropertyName: string,
+}>) => `inline ${returnType}JS::${hasteModuleName}::${structName}::${safePropertyName}() const
 {
   id const p = _v[@"${propertyName}"];
   return ${returnValue};
@@ -211,7 +213,7 @@ function serializeRegularStruct(
     structProperties: struct.properties
       .map(property => {
         const {typeAnnotation, optional} = property;
-        const propName = getSafePropertyName(property);
+        const safePropName = getSafePropertyName(property);
         const returnType = toObjCType(
           hasteModuleName,
           typeAnnotation,
@@ -219,15 +221,15 @@ function serializeRegularStruct(
         );
 
         const padding = ' '.repeat(returnType.endsWith('*') ? 0 : 1);
-        return `${returnType}${padding}${propName}() const;`;
+        return `${returnType}${padding}${safePropName}() const;`;
       })
       .join('\n      '),
   });
 
   const methods = struct.properties
     .map<string>(property => {
-      const {typeAnnotation, optional} = property;
-      const propName = getSafePropertyName(property);
+      const {typeAnnotation, optional, name: propName} = property;
+      const safePropertyName = getSafePropertyName(property);
       const returnType = toObjCType(hasteModuleName, typeAnnotation, optional);
       const returnValue = toObjCValue(
         hasteModuleName,
@@ -244,6 +246,7 @@ function serializeRegularStruct(
         returnType: returnType + padding,
         returnValue: returnValue,
         propertyName: propName,
+        safePropertyName,
       });
     })
     .join('\n');