Add a test for RCTBridgeModules that aren't auto-exported

Summary:Adds a test so that people can create RCTBridgeModules that aren't auto-exported. This is useful for when you have more than one RCTBridge and want a module to be exposed in one but not the other.

RCTBridge/RCTBatchedBridge already supports this functionality; this diff adds a test so that it doesn't break.
Closes facebook#6424

Differential Revision: D3044959

Pulled By: nicklockwood

fb-gh-sync-id: f8977249b1bf4023e704be6422ad77372d8f1714
shipit-source-id: f8977249b1bf4023e704be6422ad77372d8f1714

Examples/UIExplorer/UIExplorerUnitTests/RCTBridgeTests.m

@@ -107,12 +107,36 @@ - (void)invalidate
 
 @end
 
+// Define a module that is not explicitly registered with RCT_EXPORT_MODULE
+@interface UnregisteredTestModule : NSObject <RCTBridgeModule>
+
+@property (nonatomic, assign) BOOL testMethodCalled;
+
+@end
+
+@implementation UnregisteredTestModule
+
+@synthesize methodQueue = _methodQueue;
+
++ (NSString *)moduleName
+{
+  return @"UnregisteredTestModule";
+}
+
+RCT_EXPORT_METHOD(testMethod)
+{
+  _testMethodCalled = YES;
+}
+
+@end
+
 @interface RCTBridgeTests : XCTestCase <RCTBridgeModule>
 {
   RCTBridge *_bridge;
   __weak TestExecutor *_jsExecutor;
 
   BOOL _testMethodCalled;
+  UnregisteredTestModule *_unregisteredTestModule;
 }
 @end
 
@@ -126,8 +150,9 @@ - (void)setUp
 {
   [super setUp];
 
+  _unregisteredTestModule = [UnregisteredTestModule new];
   _bridge = [[RCTBridge alloc] initWithBundleURL:nil
-                                  moduleProvider:^{ return @[self]; }
+                                  moduleProvider:^{ return @[self, _unregisteredTestModule]; }
                                    launchOptions:nil];
 
   _bridge.executorClass = [TestExecutor class];
@@ -211,6 +236,37 @@ - (void)testCallNativeMethod
   });
 }
 
+- (void)testCallUnregisteredModuleMethod
+{
+  NSString *injectedStuff;
+  RUN_RUNLOOP_WHILE(!(injectedStuff = _jsExecutor.injectedStuff[@"__fbBatchedBridgeConfig"]));
+  XCTAssertNotNil(injectedStuff);
+
+  __block NSNumber *testModuleID = nil;
+  __block NSNumber *testMethodID = nil;
+
+  NSArray *remoteModuleConfig = RCTJSONParse(injectedStuff, NULL)[@"remoteModuleConfig"];
+  [remoteModuleConfig enumerateObjectsUsingBlock:^(id moduleConfig, NSUInteger i, __unused BOOL *stop) {
+    if ([moduleConfig isKindOfClass:[NSArray class]] && [moduleConfig[0] isEqualToString:@"UnregisteredTestModule"]) {
+      testModuleID = @(i);
+      testMethodID = @([moduleConfig[1] indexOfObject:@"testMethod"]);
+      *stop = YES;
+    }
+  }];
+
+  XCTAssertNotNil(testModuleID);
+  XCTAssertNotNil(testMethodID);
+
+  NSArray *args = @[];
+  NSArray *buffer = @[@[testModuleID], @[testMethodID], @[args]];
+
+  [_bridge.batchedBridge handleBuffer:buffer];
+
+  dispatch_sync(_unregisteredTestModule.methodQueue, ^{
+    XCTAssertTrue(_unregisteredTestModule.testMethodCalled);
+  });
+}
+
 - (void)DISABLED_testBadArgumentsCount
 {
   //NSArray *bufferWithMissingArgument = @[@[@1], @[@0], @[@[@1234, @5678, @"stringy", @{@"a": @1}/*, @42*/]], @[], @1234567];