From 8f2bcf3563d6234030243b47e7967394ae0ba6a7 Mon Sep 17 00:00:00 2001
From: Joshua Gross <joshua.gross@gmail.com>
Date: Tue, 24 Sep 2019 16:26:08 -0700
Subject: [PATCH] [React Native] Improve logging for missing view configs and
 invalid view config getter functions

---
 .../ReactPrivate/ReactNativeViewConfigRegistry.js      |  9 ++++++++-
 .../src/__tests__/ReactNativeError-test.internal.js    | 10 ++++++++++
 .../react-native/ReactNativeViewConfigRegistry.js      |  9 ++++++++-
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/packages/react-native-renderer/src/__mocks__/react-native/Libraries/ReactPrivate/ReactNativeViewConfigRegistry.js b/packages/react-native-renderer/src/__mocks__/react-native/Libraries/ReactPrivate/ReactNativeViewConfigRegistry.js
index 05c8b93c9ee58..a4dd86df63f21 100644
--- a/packages/react-native-renderer/src/__mocks__/react-native/Libraries/ReactPrivate/ReactNativeViewConfigRegistry.js
+++ b/packages/react-native-renderer/src/__mocks__/react-native/Libraries/ReactPrivate/ReactNativeViewConfigRegistry.js
@@ -78,6 +78,12 @@ exports.register = function(name: string, callback: ViewConfigGetter): string {
     'Tried to register two views with the same name %s',
     name,
   );
+  invariant(
+    typeof callback === 'function',
+    'View config getter callback must be a function: %s (received %s)',
+    name,
+    callback === null ? 'null' : typeof callback,
+  );
   viewConfigCallbacks.set(name, callback);
   return name;
 };
@@ -94,8 +100,9 @@ exports.get = function(name: string): ReactNativeBaseComponentViewConfig<> {
     if (typeof callback !== 'function') {
       invariant(
         false,
-        'View config not found for name %s.%s',
+        'View config registration not found for name %s (received %s).%s',
         name,
+        callback === null ? 'null' : typeof callback,
         typeof name[0] === 'string' && /[a-z]/.test(name[0])
           ? ' Make sure to start component names with a capital letter.'
           : '',
diff --git a/packages/react-native-renderer/src/__tests__/ReactNativeError-test.internal.js b/packages/react-native-renderer/src/__tests__/ReactNativeError-test.internal.js
index 9abf0ee21aecb..bb49369fe4399 100644
--- a/packages/react-native-renderer/src/__tests__/ReactNativeError-test.internal.js
+++ b/packages/react-native-renderer/src/__tests__/ReactNativeError-test.internal.js
@@ -32,6 +32,16 @@ describe('ReactNativeError', () => {
         .computeComponentStackForErrorReporting;
   });
 
+  it('should throw error if null component registration getter is used', () => {
+    expect(() => {
+      try {
+        createReactNativeComponentClass('View', null)
+      } catch (e) {
+        throw new Error(e.toString());
+      }
+    }).toThrow('Invariant Violation: View config getter callback must be a function: View (received null)');
+  });
+
   it('should be able to extract a component stack from a native view', () => {
     const View = createReactNativeComponentClass('View', () => ({
       validAttributes: {foo: true},
diff --git a/scripts/rollup/shims/react-native/ReactNativeViewConfigRegistry.js b/scripts/rollup/shims/react-native/ReactNativeViewConfigRegistry.js
index 7290c84546c50..b43ad39ded9a2 100644
--- a/scripts/rollup/shims/react-native/ReactNativeViewConfigRegistry.js
+++ b/scripts/rollup/shims/react-native/ReactNativeViewConfigRegistry.js
@@ -75,6 +75,12 @@ exports.register = function(name: string, callback: ViewConfigGetter): string {
     'Tried to register two views with the same name %s',
     name,
   );
+  invariant(
+    typeof callback === 'function',
+    'View config getter callback must be a function: %s (received %s)',
+    name,
+    callback === null ? 'null' : typeof callback,
+  );
   viewConfigCallbacks.set(name, callback);
   return name;
 };
@@ -91,8 +97,9 @@ exports.get = function(name: string): ReactNativeBaseComponentViewConfig<> {
     if (typeof callback !== 'function') {
       invariant(
         false,
-        'View config not found for name %s.%s',
+        'View config registration not found for name %s (received %s).%s',
         name,
+        callback === null ? 'null' : typeof callback,
         typeof name[0] === 'string' && /[a-z]/.test(name[0])
           ? ' Make sure to start component names with a capital letter.'
           : '',