refactor: add code review recommendations

android/cpp-adapter.cpp

@@ -5,6 +5,22 @@
 using namespace facebook::jsi;
 
 // Optional:
+void bridgePlatformFunctions(Runtime &jsi);
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_jsimodule_JsiModuleModule_jniBridgeJSIFunctions(JNIEnv *env, jobject thiz, jobject context,
+                                                         jlong jsi_pointer)
+{
+    Runtime *jsi = reinterpret_cast<Runtime *>(jsi_pointer);
+    if (jsi)
+    {
+        jsimodule::bridgeJSIFunctions(*jsi);
+
+        // Optional: bridge some platform specific logic too.
+        bridgePlatformFunctions(*jsi);
+    }
+}
+
 void bridgePlatformFunctions(Runtime &jsi)
 {
     auto getDeviceName = Function::createFromHostFunction(jsi,
@@ -20,18 +36,4 @@ void bridgePlatformFunctions(Runtime &jsi)
                                                           });
 
     jsi.global().setProperty(jsi, "getDeviceName", std::move(getDeviceName));
-}
-
-extern "C" JNIEXPORT void JNICALL
-Java_com_jsimodule_JsiModuleModule_jniBridgeJSIFunctions(JNIEnv *env, jobject thiz, jobject context,
-                                                         jlong jsi_pointer)
-{
-    Runtime *jsi = reinterpret_cast<Runtime *>(jsi_pointer);
-    if (jsi)
-    {
-        jsimodule::bridgeJSIFunctions(*jsi);
-
-        // Optional: bridge some platform specific logic too.
-        bridgePlatformFunctions(*jsi);
-    }
 }

cpp/react-native-jsi-module.cpp

@@ -1,16 +1,15 @@
-#include <jsi/jsi.h>
 #include "react-native-jsi-module.h"
 
 extern "C"
 {
-  double multiply(double a, double b); // Declaration of the Rust function
+  // For instance, C++'s `double` type is the equivalent of Rust's `f64`
+  double rust_multiply(double a, double b);
 }
 
 namespace jsimodule
 {
   void bridgeJSIFunctions(Runtime &jsi)
   {
-    // Define `multiplyJSI` using JSI idioms.
     auto multiplyJSI = Function::createFromHostFunction(
         jsi,
         PropNameID::forAscii(jsi, "multiplyJSI"),
@@ -25,10 +24,11 @@ namespace jsimodule
           double a = arguments[0].asNumber();
           double b = arguments[1].asNumber();
 
-          return multiply(a, b);
+          double ret = rust_multiply(a, b);
+
+          return Value(ret);
         });
 
-    // Export the `multiply` function to React Native's global object
     jsi.global().setProperty(jsi, "multiply", std::move(multiplyJSI));
   }
 

ios/JsiModule.h

@@ -4,5 +4,4 @@
 
 #import <React/RCTBridgeModule.h>
 @interface JsiModule : NSObject <RCTBridgeModule>
-
 @end

rust_multiply_lib/.cargo/config.toml

@@ -0,0 +1,16 @@
+# Convenience shorthands.
+[alias]
+build-ios = ["build", "--target", "aarch64-apple-ios"]
+build-android = ["build", "--target", "aarch64-linux-android"]
+
+# Linker configuration settings.
+[target.aarch64-apple-ios]
+rustflags = [
+  "-C", "link-arg=-isysroot", "-C", "link-arg=$(xcrun --sdk iphoneos --show-sdk-path)",
+  "-C", "link-arg=-arch", "-C", "link-arg=arm64",
+  "-C", "link-arg=-mios-version-min=10.0"
+]
+
+[target.aarch64-linux-android]
+linker = "aarch64-linux-android21-clang"
+ar = "aarch64-linux-android-ar"

rust_multiply_lib/Cargo.toml

@@ -3,10 +3,10 @@ name = "rust_multiply_lib"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-
 [lib]
-crate-type = ["staticlib"]
-
+crate-type = [
+    "staticlib", # Generates a C-compatible static library.
+    # Optional: Also compile as a Rust library to enable Cargo features 
+    # like `tests/`, doc tests, and `examples/`
+    "lib",
+]

rust_multiply_lib/src/lib.rs

@@ -1,4 +1,4 @@
-#[no_mangle]
-pub extern "C" fn multiply(a: f64, b: f64) -> f64 {
+#[no_mangle] pub extern "C"
+fn rust_multiply(a: f64, b: f64) -> f64 {
     a * b
-}
+}

src/index.tsx

@@ -6,16 +6,16 @@ const LINKING_ERROR =
   '- You rebuilt the app after installing the package\n' +
   '- You are not using Expo Go\n';
 
-const JsiModule = NativeModules.JsiModule
-  ? NativeModules.JsiModule
-  : new Proxy(
-      {},
-      {
-        get() {
-          throw new Error(LINKING_ERROR);
-        },
-      }
-    );
+const JsiModule =
+  NativeModules.JsiModule ??
+  new Proxy(
+    {},
+    {
+      get() {
+        throw new Error(LINKING_ERROR);
+      },
+    }
+  );
 
 const jsiCore = global as unknown as {
   multiply(a: number, b: number): number;