Refactor and test RNSentryModuleImpl.fetchNativeDeviceContexts (#4253)

* Refactor fetchNativeDeviceContexts for testability

* Test fetchNativeDeviceContexts

* Adds new line at the end

packages/core/RNSentryAndroidTester/app/src/androidTest/java/io/sentry/react/RNSentryModuleImplTest.kt

@@ -0,0 +1,86 @@
+package io.sentry.react
+
+import android.content.Context
+import androidx.test.platform.app.InstrumentationRegistry
+import com.facebook.react.bridge.PromiseImpl
+import com.facebook.react.bridge.ReactApplicationContext
+import com.facebook.react.bridge.WritableMap
+import com.facebook.soloader.SoLoader
+import io.sentry.Breadcrumb
+import io.sentry.Scope
+import io.sentry.SentryOptions
+import io.sentry.android.core.SentryAndroidOptions
+import org.junit.Assert.assertEquals
+import org.junit.Assert.fail
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.junit.runners.JUnit4
+
+@RunWith(JUnit4::class)
+class RNSentryModuleImplTest {
+
+    private lateinit var module: RNSentryModuleImpl
+    private lateinit var context: Context
+
+    @Before
+    fun setUp() {
+        context = InstrumentationRegistry.getInstrumentation().targetContext
+        SoLoader.init(context, false)
+        val reactContext = ReactApplicationContext(context)
+        module = RNSentryModuleImpl(reactContext)
+    }
+
+    @Test
+    fun fetchNativeDeviceContextsWithNullContext() {
+        val options = SentryAndroidOptions()
+        val scope = Scope(options)
+        val promise = PromiseImpl({
+            assertEquals(1, it.size)
+            assertEquals(null, it[0])
+        }, {
+            fail("Promise was rejected unexpectedly")
+        })
+        module.fetchNativeDeviceContexts(promise, options, null, scope)
+    }
+
+    @Test
+    fun fetchNativeDeviceContextsWithInvalidSentryOptions() {
+        class NotAndroidSentryOptions : SentryOptions()
+
+        val options = NotAndroidSentryOptions()
+        val scope = Scope(options)
+        val promise = PromiseImpl({
+            assertEquals(1, it.size)
+            assertEquals(null, it[0])
+        }, {
+            fail("Promise was rejected unexpectedly")
+        })
+        module.fetchNativeDeviceContexts(promise, options, context, scope)
+    }
+
+    @Test
+    fun fetchNativeDeviceContextsFiltersBreadcrumbs() {
+        val options = SentryAndroidOptions().apply { maxBreadcrumbs = 5 }
+        val scope = Scope(options)
+        scope.addBreadcrumb(Breadcrumb("Breadcrumb1-RN").apply { origin = "react-native" })
+        scope.addBreadcrumb(Breadcrumb("Breadcrumb2-Native"))
+        scope.addBreadcrumb(Breadcrumb("Breadcrumb3-Native").apply { origin = "java" })
+        scope.addBreadcrumb(Breadcrumb("Breadcrumb2-RN").apply { origin = "react-native" })
+        scope.addBreadcrumb(Breadcrumb("Breadcrumb2-RN").apply { origin = "react-native" })
+
+        val promise = PromiseImpl({
+            assertEquals(1, it.size)
+            assertEquals(true, it[0] is WritableMap)
+            val actual = it[0] as WritableMap
+            val breadcrumbs = actual.getArray("breadcrumbs")
+            assertEquals(2, breadcrumbs?.size())
+            assertEquals("Breadcrumb2-Native", breadcrumbs?.getMap(0)?.getString("message"))
+            assertEquals("Breadcrumb3-Native", breadcrumbs?.getMap(1)?.getString("message"))
+        }, {
+            fail("Promise was rejected unexpectedly")
+        })
+
+        module.fetchNativeDeviceContexts(promise, options, context, scope)
+    }
+}

packages/core/android/src/main/java/io/sentry/react/RNSentryModuleImpl.java

@@ -888,18 +888,24 @@ private String readStringFromFile(File path) throws IOException {
 
   public void fetchNativeDeviceContexts(Promise promise) {
     final @NotNull SentryOptions options = HubAdapter.getInstance().getOptions();
+    final @Nullable Context context = this.getReactApplicationContext().getApplicationContext();
+    final @Nullable IScope currentScope = InternalSentrySdk.getCurrentScope();
+    fetchNativeDeviceContexts(promise, options, context, currentScope);
+  }
+
+  protected void fetchNativeDeviceContexts(
+      Promise promise,
+      final @NotNull SentryOptions options,
+      final @Nullable Context context,
+      final @Nullable IScope currentScope) {
     if (!(options instanceof SentryAndroidOptions)) {
       promise.resolve(null);
       return;
     }
-
-    final @Nullable Context context = this.getReactApplicationContext().getApplicationContext();
     if (context == null) {
       promise.resolve(null);
       return;
     }
-
-    final @Nullable IScope currentScope = InternalSentrySdk.getCurrentScope();
     if (currentScope != null) {
       // Remove react-native breadcrumbs
       Iterator<Breadcrumb> breadcrumbsIterator = currentScope.getBreadcrumbs().iterator();