From 32e5c97d11e390e6a3d3ce6a2ab7443daed09747 Mon Sep 17 00:00:00 2001
From: Joshua Gross <joshua.gross@gmail.com>
Date: Tue, 24 Sep 2019 17:46:21 -0700
Subject: [PATCH] [React Native] Improve errors for invalid ViewConfig getter
 functions (#16879)

* [React Native] Improve logging for missing view configs and invalid view config getter functions

* [React Native] Improve logging for missing view configs and invalid view config getter functions
---
 .../ReactPrivate/ReactNativeViewConfigRegistry.js    |  9 ++++++++-
 .../src/__tests__/ReactNativeError-test.internal.js  | 12 ++++++++++++
 .../react-native/ReactNativeViewConfigRegistry.js    |  9 ++++++++-
 3 files changed, 28 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..4fe8e6c56fe5b 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 for component `%s` must be a function (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 getter callback for component `%s` must be a function (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..f6a78667eda36 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 +32,18 @@ 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 for component `View` must be a function (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..2173fc84b3e70 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 for component `%s` must be a function (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 getter callback for component `%s` must be a function (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.'
           : '',