Wrap NullPointerExceptions when thrown by native code called from JS for readability

Author: hsource

Libraries/ReactNative/PaperUIManager.js

@@ -105,6 +105,23 @@ const UIManagerJS = {
   hasViewManagerConfig(viewManagerName: string): boolean {
     return getViewManagerConfig(viewManagerName) != null;
   },
+  dispatchViewManagerCommand(
+    reactTag: number,
+    commandName: number | string,
+    commandArgs: any[],
+  ) {
+    if (typeof reactTag !== 'number') {
+      let stringifiedArgs = '(failed to stringify)';
+      try {
+        stringifiedArgs = JSON.stringify(commandArgs);
+      } catch (err) {
+        // Do nothing. We have a default message
+      }
+      throw new Error(`dispatchViewManagerCommand: found null reactTag with args ${stringifiedArgs}`);
+    }
+
+    return NativeUIManager.dispatchViewManagerCommand(reactTag, commandName, commandArgs);
+  },
 };
 
 // TODO (T45220498): Remove this.

ReactAndroid/src/main/java/com/facebook/react/bridge/JavaMethodWrapper.java

@@ -10,6 +10,9 @@
 import static com.facebook.infer.annotation.Assertions.assertNotNull;
 import static com.facebook.systrace.Systrace.TRACE_TAG_REACT_JAVA_BRIDGE;
 
+import android.text.Editable;
+import android.text.SpannableStringBuilder;
+
 import androidx.annotation.Nullable;
 import com.facebook.debug.holder.PrinterHolder;
 import com.facebook.debug.tags.ReactDebugOverlayTags;
@@ -356,37 +359,44 @@ public void invoke(JSInstance jsInstance, ReadableArray parameters) {
               mArgumentExtractors[i].extractArgument(jsInstance, parameters, jsArgumentsConsumed);
           jsArgumentsConsumed += mArgumentExtractors[i].getJSArgumentsNeeded();
         }
-      } catch (UnexpectedNativeTypeException e) {
+      } catch (UnexpectedNativeTypeException | NullPointerException e) {
         throw new NativeArgumentsParseException(
             e.getMessage()
                 + " (constructing arguments for "
                 + traceName
                 + " at argument index "
                 + getAffectedRange(
                     jsArgumentsConsumed, mArgumentExtractors[i].getJSArgumentsNeeded())
-                + ")",
+                + ") with parameters "
+                + parameters.toArrayList(),
             e);
       }
 
       try {
         mMethod.invoke(mModuleWrapper.getModule(), mArguments);
-      } catch (IllegalArgumentException ie) {
-        throw new RuntimeException("Could not invoke " + traceName, ie);
-      } catch (IllegalAccessException iae) {
-        throw new RuntimeException("Could not invoke " + traceName, iae);
+      } catch (IllegalArgumentException | IllegalAccessException e) {
+        throw new RuntimeException(createInvokeExceptionMessage(traceName, parameters), e);
       } catch (InvocationTargetException ite) {
         // Exceptions thrown from native module calls end up wrapped in InvocationTargetException
         // which just make traces harder to read and bump out useful information
         if (ite.getCause() instanceof RuntimeException) {
           throw (RuntimeException) ite.getCause();
         }
-        throw new RuntimeException("Could not invoke " + traceName, ite);
+        throw new RuntimeException(createInvokeExceptionMessage(traceName, parameters), ite);
       }
     } finally {
       SystraceMessage.endSection(TRACE_TAG_REACT_JAVA_BRIDGE).flush();
     }
   }
 
+  /**
+   * Makes it easier to determine the cause of an error invoking a native method from Javascript
+   * code by adding the function and parameters.
+   */
+  private static String createInvokeExceptionMessage(String traceName, ReadableArray parameters) {
+    return "Could not invoke " + traceName + " with parameters " + parameters.toArrayList();
+  }
+
   /**
    * Determines how the method is exported in JavaScript: METHOD_TYPE_ASYNC for regular methods
    * METHOD_TYPE_PROMISE for methods that return a promise object to the caller. METHOD_TYPE_SYNC

WanderlogPatches.md

@@ -48,3 +48,6 @@ rebase on upstream's `main`
 - Prevent crash when runAnimationStep called with low frameTimeNanos
   - Summary: React Native was crashing on OnePlus and Oppo devices. This is a workaround
   - Pull request: https://github.com/facebook/react-native/pull/37487
+- Wrap NullPointerExceptions when thrown by native code called from JS for readability
+  - Summary: These crashing exceptions were really hard to debug in Bugsnag since they don't print the method name. We wrap it and add that.
+  - Pull request: https://github.com/facebook/react-native/pull/38060