[Bridge] RCT_REMAP_METHOD(js_name, selector)

Summary: cc @a2 @nicklockwood This diff introduces a new macro called `RCT_EXPORT_NAMED_METHOD`, which is like `RCT_EXPORT_METHOD` but lets you choose the name of the method in JS. This diff is backwards compatible with the `RCT_EXPORT_METHOD` and legacy `RCT_EXPORT` macros. The entries in the data segment now contain `__func__`, the Obj-C selector signature, and the JS name. If the JS name is `NULL`, we take the legacy `RCT_EXPORT` code path. If the JS name is an empty string, we use the Obj-C selector's name up to the first colon (that is, the behavior of `RCT_EXPORT_METHOD`). Since there are three values in each data segment entry, the macros now specify 1-byte alignment. Without the byte alignment, the compiler defaults to 2-byte alignment meaning that each entry takes up 4 bytes instead of 3. The extra byte isn't a concern but being explicit about the alignment should reduce compiler surprises. Closes #802 Github Author: James Ide <[email protected]> Test Plan: Imported from GitHub, without a `Test Plan:` line.
facebook · Apr 14, 2015 · e193a13 · e193a13
1 parent 5bbb351
commit e193a13
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Showing 4 changed files with 122 additions and 102 deletions.
diff --git a/React/Base/RCTBridge.m b/React/Base/RCTBridge.m
@@ -219,20 +219,22 @@ @implementation RCTModuleMethod
 
 static Class _globalExecutorClass;
 
-NS_INLINE NSString *RCTStringUpToFirstArgument(NSString *methodName) {
+static NSString *RCTStringUpToFirstArgument(NSString *methodName)
+{
   NSRange colonRange = [methodName rangeOfString:@":"];
   if (colonRange.length) {
     methodName = [methodName substringToIndex:colonRange.location];
   }
   return methodName;
 }
 
-- (instancetype)initWithMethodName:(NSString *)methodName
-                      JSMethodName:(NSString *)JSMethodName
+- (instancetype)initWithReactMethodName:(NSString *)reactMethodName
+                         objCMethodName:(NSString *)objCMethodName
+                           JSMethodName:(NSString *)JSMethodName
 {
   if ((self = [super init])) {
-    _methodName = methodName;
-    NSArray *parts = [[methodName substringWithRange:(NSRange){2, methodName.length - 3}] componentsSeparatedByString:@" "];
+    _methodName = reactMethodName;
+    NSArray *parts = [[reactMethodName substringWithRange:(NSRange){2, reactMethodName.length - 3}] componentsSeparatedByString:@" "];
 
     // Parse class and method
     _moduleClassName = parts[0];
@@ -246,7 +248,7 @@ - (instancetype)initWithMethodName:(NSString *)methodName
       // New format
       NSString *selectorString = [parts[1] substringFromIndex:14];
       _selector = NSSelectorFromString(selectorString);
-      _JSMethodName = RCTStringUpToFirstArgument(selectorString);
+      _JSMethodName = JSMethodName ?: RCTStringUpToFirstArgument(selectorString);
 
       static NSRegularExpression *regExp;
       if (!regExp) {
@@ -258,8 +260,8 @@ - (instancetype)initWithMethodName:(NSString *)methodName
       }
 
       argumentNames = [NSMutableArray array];
-      [regExp enumerateMatchesInString:JSMethodName options:0 range:NSMakeRange(0, JSMethodName.length) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
-        NSString *argumentName = [JSMethodName substringWithRange:[result rangeAtIndex:1]];
+      [regExp enumerateMatchesInString:objCMethodName options:0 range:NSMakeRange(0, objCMethodName.length) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
+        NSString *argumentName = [objCMethodName substringWithRange:[result rangeAtIndex:1]];
         [(NSMutableArray *)argumentNames addObject:argumentName];
       }];
     } else {
@@ -270,14 +272,15 @@ - (instancetype)initWithMethodName:(NSString *)methodName
     }
 
     // Extract class and method details
-    _isClassMethod = [methodName characterAtIndex:0] == '+';
+    _isClassMethod = [reactMethodName characterAtIndex:0] == '+';
     _moduleClass = NSClassFromString(_moduleClassName);
 
 #if DEBUG
+
     // Sanity check
     RCTAssert([_moduleClass conformsToProtocol:@protocol(RCTBridgeModule)],
               @"You are attempting to export the method %@, but %@ does not \
-              conform to the RCTBridgeModule Protocol", methodName, _moduleClassName);
+              conform to the RCTBridgeModule Protocol", objCMethodName, _moduleClassName);
 #endif
 
     // Get method signature
@@ -290,26 +293,26 @@ - (instancetype)initWithMethodName:(NSString *)methodName
     NSMutableArray *argumentBlocks = [[NSMutableArray alloc] initWithCapacity:numberOfArguments - 2];
 
 #define RCT_ARG_BLOCK(_logic) \
-[argumentBlocks addObject:^(RCTBridge *bridge, NSInvocation *invocation, NSUInteger index, id json) { \
-_logic \
-[invocation setArgument:&value atIndex:index]; \
-}]; \
+  [argumentBlocks addObject:^(RCTBridge *bridge, NSInvocation *invocation, NSUInteger index, id json) { \
+    _logic \
+    [invocation setArgument:&value atIndex:index]; \
+  }]; \
 
     void (^addBlockArgument)(void) = ^{
       RCT_ARG_BLOCK(
-                    if (json && ![json isKindOfClass:[NSNumber class]]) {
-                      RCTLogError(@"Argument %tu (%@) of %@.%@ should be a number", index,
-                                  json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName);
-                      return;
-                    }
-
-                    // Marked as autoreleasing, because NSInvocation doesn't retain arguments
-                    __autoreleasing id value = (json ? ^(NSArray *args) {
-        [bridge _invokeAndProcessModule:@"BatchedBridge"
-                                 method:@"invokeCallbackAndReturnFlushedQueue"
-                              arguments:@[json, args]];
-      } : ^(NSArray *unused) {});
-                    )
+        if (json && ![json isKindOfClass:[NSNumber class]]) {
+          RCTLogError(@"Argument %tu (%@) of %@.%@ should be a number", index,
+                      json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName);
+          return;
+        }
+
+        // Marked as autoreleasing, because NSInvocation doesn't retain arguments
+        __autoreleasing id value = (json ? ^(NSArray *args) {
+          [bridge _invokeAndProcessModule:@"BatchedBridge"
+                                   method:@"invokeCallbackAndReturnFlushedQueue"
+                                arguments:@[json, args]];
+        } : ^(NSArray *unused) {});
+      )
     };
 
     void (^defaultCase)(const char *) = ^(const char *argumentType) {
@@ -333,11 +336,11 @@ - (instancetype)initWithMethodName:(NSString *)methodName
           switch (argumentType[0]) {
 
 #define RCT_CONVERT_CASE(_value, _type) \
-case _value: { \
-_type (*convert)(id, SEL, id) = (typeof(convert))[RCTConvert methodForSelector:selector]; \
-RCT_ARG_BLOCK( _type value = convert([RCTConvert class], selector, json); ) \
-break; \
-}
+  case _value: { \
+    _type (*convert)(id, SEL, id) = (typeof(convert))[RCTConvert methodForSelector:selector]; \
+    RCT_ARG_BLOCK( _type value = convert([RCTConvert class], selector, json); ) \
+    break; \
+  }
 
               RCT_CONVERT_CASE(':', SEL)
               RCT_CONVERT_CASE('*', const char *)
@@ -371,33 +374,33 @@ - (instancetype)initWithMethodName:(NSString *)methodName
         switch (argumentType[0]) {
 
 #define RCT_CASE(_value, _class, _logic) \
-case _value: {                   \
-RCT_ARG_BLOCK( \
-if (json && ![json isKindOfClass:[_class class]]) { \
-RCTLogError(@"Argument %tu (%@) of %@.%@ should be of type %@", index, \
-json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName, [_class class]); \
-return; \
-} \
-_logic \
-) \
-break; \
-}
+  case _value: {                   \
+    RCT_ARG_BLOCK( \
+      if (json && ![json isKindOfClass:[_class class]]) { \
+        RCTLogError(@"Argument %tu (%@) of %@.%@ should be of type %@", index, \
+          json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName, [_class class]); \
+        return; \
+      } \
+      _logic \
+    ) \
+    break; \
+  }
 
             RCT_CASE(':', NSString, SEL value = NSSelectorFromString(json); )
             RCT_CASE('*', NSString, const char *value = [json UTF8String]; )
 
 #define RCT_SIMPLE_CASE(_value, _type, _selector) \
-case _value: {                              \
-RCT_ARG_BLOCK( \
-if (json && ![json respondsToSelector:@selector(_selector)]) { \
-RCTLogError(@"Argument %tu (%@) of %@.%@ does not respond to selector: %@", \
-index, json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName, @#_selector); \
-return; \
-} \
-_type value = [json _selector];                     \
-) \
-break; \
-}
+  case _value: {                              \
+    RCT_ARG_BLOCK( \
+      if (json && ![json respondsToSelector:@selector(_selector)]) { \
+        RCTLogError(@"Argument %tu (%@) of %@.%@ does not respond to selector: %@", \
+          index, json, RCTBridgeModuleNameForClass(_moduleClass), _JSMethodName, @#_selector); \
+        return; \
+      } \
+      _type value = [json _selector];                     \
+    ) \
+    break; \
+  }
 
             RCT_SIMPLE_CASE('c', char, charValue)
             RCT_SIMPLE_CASE('C', unsigned char, unsignedCharValue)
@@ -432,6 +435,7 @@ - (void)invokeWithBridge:(RCTBridge *)bridge
 {
 
 #if DEBUG
+
   // Sanity check
   RCTAssert([module class] == _moduleClass, @"Attempted to invoke method \
             %@ on a module of class %@", _methodName, [module class]);
@@ -496,15 +500,24 @@ - (NSString *)description
 
     for (RCTHeaderValue addr = section->offset;
          addr < section->offset + section->size;
-         addr += sizeof(const char **) * 2) {
+         addr += sizeof(const char **) * 3) {
 
       // Get data entry
       const char **entries = (const char **)(mach_header + addr);
 
       // Create method
-      RCTModuleMethod *moduleMethod =
-      [[RCTModuleMethod alloc] initWithMethodName:@(entries[0])
-                                     JSMethodName:strlen(entries[1]) ? @(entries[1]) : nil];
+      RCTModuleMethod *moduleMethod;
+      if (entries[2] == NULL) {
+
+        // Legacy support for RCT_EXPORT()
+        moduleMethod = [[RCTModuleMethod alloc] initWithReactMethodName:@(entries[0])
+                                                         objCMethodName:@(entries[0])
+                                                           JSMethodName:strlen(entries[1]) ? @(entries[1]) : nil];
+      } else {
+        moduleMethod = [[RCTModuleMethod alloc] initWithReactMethodName:@(entries[0])
+                                                         objCMethodName:strlen(entries[1]) ? @(entries[1]) : nil
+                                                           JSMethodName:strlen(entries[2]) ? @(entries[2]) : nil];
+      }
 
       // Cache method
       NSArray *methods = methodsByModuleClassName[moduleMethod.moduleClassName];
@@ -560,15 +573,15 @@ - (NSString *)description
       NSMutableDictionary *methodsByName = [NSMutableDictionary dictionaryWithCapacity:methods.count];
       [methods enumerateObjectsUsingBlock:^(RCTModuleMethod *method, NSUInteger methodID, BOOL *_stop) {
         methodsByName[method.JSMethodName] = @{
-                                               @"methodID": @(methodID),
-                                               @"type": @"remote",
-                                               };
+          @"methodID": @(methodID),
+          @"type": @"remote",
+        };
       }];
 
       NSDictionary *module = @{
-                               @"moduleID": @(moduleID),
-                               @"methods": methodsByName
-                               };
+        @"moduleID": @(moduleID),
+        @"methods": methodsByName
+      };
 
       remoteModuleConfigByClassName[NSStringFromClass(moduleClass)] = module;
     }];
@@ -639,9 +652,9 @@ - (NSString *)description
       NSDictionary *module = localModules[moduleName];
       if (!module) {
         module = @{
-                   @"moduleID": @(localModules.count),
-                   @"methods": [[NSMutableDictionary alloc] init]
-                   };
+          @"moduleID": @(localModules.count),
+          @"methods": [[NSMutableDictionary alloc] init]
+        };
         localModules[moduleName] = module;
       }
 
@@ -650,9 +663,9 @@ - (NSString *)description
       NSMutableDictionary *methods = module[@"methods"];
       if (!methods[methodName]) {
         methods[methodName] = @{
-                                @"methodID": @(methods.count),
-                                @"type": @"local"
-                                };
+          @"methodID": @(methods.count),
+          @"type": @"local"
+        };
       }
 
       // Add module and method lookup
@@ -741,9 +754,9 @@ - (void)setUp
 
   // Inject module data into JS context
   NSString *configJSON = RCTJSONStringify(@{
-                                            @"remoteModuleConfig": RCTRemoteModulesConfig(_modulesByName),
-                                            @"localModulesConfig": RCTLocalModulesConfig()
-                                            }, NULL);
+    @"remoteModuleConfig": RCTRemoteModulesConfig(_modulesByName),
+    @"localModulesConfig": RCTLocalModulesConfig()
+  }, NULL);
   dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);
   [_javaScriptExecutor injectJSONText:configJSON
                   asGlobalObjectNamed:@"__fbBatchedBridgeConfig" callback:^(id err) {

diff --git a/React/Base/RCTBridgeModule.h b/React/Base/RCTBridgeModule.h
@@ -32,7 +32,7 @@ typedef void (^RCTResponseSenderBlock)(NSArray *response);
 @property (nonatomic, weak) RCTBridge *bridge;
 
 /**
- * Place this macro in your class implementation, to automatically register
+ * Place this macro in your class implementation to automatically register
  * your module with the bridge when it loads. The optional js_name argument
  * will be used as the JS module name. If omitted, the JS module name will
  * match the Objective-C class name.
@@ -41,23 +41,11 @@ typedef void (^RCTResponseSenderBlock)(NSArray *response);
   + (NSString *)moduleName { __attribute__((used, section("__DATA,RCTExportModule" \
   ))) static const char *__rct_export_entry__ = { __func__ }; return @#js_name; }
 
-/**
- * Place this macro inside the method body of any method you want to expose
- * to JS. The optional js_name argument will be used as the JS method name
- * (the method will be namespaced to the module name, as specified above).
- * If omitted, the JS method name will match the first part of the Objective-C
- * method selector name (up to the first colon).
- */
-#define RCT_EXPORT(js_name) \
-  _Pragma("message(\"RCT_EXPORT is deprecated. Use RCT_EXPORT_METHOD instead.\")") \
-  __attribute__((used, section("__DATA,RCTExport"))) \
-  static const char *__rct_export_entry__[] = { __func__, #js_name }
-
 /**
  * Wrap the parameter line of your method implementation with this macro to
- * expose it to JS. Unlike the deprecated RCT_EXPORT, this macro does not take
- * a js_name argument and the exposed method will match the first part of the
- * Objective-C method selector name (up to the first colon).
+ * expose it to JS. By default the exposed method will match the first part of
+ * the Objective-C method selector name (up to the first colon). Use
+ * RCT_REMAP_METHOD to specify the JS name of the method.
  *
  * For example, in ModuleName.m:
  *
@@ -74,12 +62,33 @@ typedef void (^RCTResponseSenderBlock)(NSArray *response);
  * and is exposed to JavaScript as `NativeModules.ModuleName.doSomething`.
  */
 #define RCT_EXPORT_METHOD(method) \
+  RCT_REMAP_METHOD(, method)
+
+/**
+ * Similar to RCT_EXPORT_METHOD but lets you set the JS name of the exported
+ * method. Example usage:
+ *
+ * RCT_REMAP_METHOD(executeQueryWithParameters,
+ *   executeQuery:(NSString *)query parameters:(NSDictionary *)parameters)
+ * { ... }
+ */
+#define RCT_REMAP_METHOD(js_name, method) \
   - (void)__rct_export__##method { \
     __attribute__((used, section("__DATA,RCTExport"))) \
-    static const char *__rct_export_entry__[] = { __func__, #method }; \
+    __attribute__((__aligned__(1))) \
+    static const char *__rct_export_entry__[] = { __func__, #method, #js_name }; \
   } \
   - (void)method
 
+/**
+ * Deprecated, do not use.
+ */
+#define RCT_EXPORT(js_name) \
+  _Pragma("message(\"RCT_EXPORT is deprecated. Use RCT_EXPORT_METHOD instead.\")") \
+  __attribute__((used, section("__DATA,RCTExport"))) \
+  __attribute__((__aligned__(1))) \
+  static const char *__rct_export_entry__[] = { __func__, #js_name, NULL }
+
 /**
  * Injects constants into JS. These constants are made accessible via
  * NativeModules.ModuleName.X. This method is called when the module is

diff --git a/React/Base/RCTConvert.h b/React/Base/RCTConvert.h
@@ -135,6 +135,11 @@ BOOL RCTSetProperty(id target, NSString *keyPath, SEL type, id json);
  */
 BOOL RCTCopyProperty(id target, id source, NSString *keyPath);
 
+/**
+ * Underlying implementation of RCT_ENUM_CONVERTER macro. Ignore this.
+ */
+NSNumber *RCTConverterEnumValue(const char *, NSDictionary *, NSNumber *, id);
+
 #ifdef __cplusplus
 }
 #endif
@@ -169,13 +174,11 @@ RCT_CUSTOM_CONVERTER(type, name, [json getter])
 /**
  * This macro is similar to RCT_CONVERTER, but specifically geared towards
  * numeric types. It will handle string input correctly, and provides more
- * detailed error reporting if a wrong value is passed in.
+ * detailed error reporting if an invalid value is passed in.
  */
 #define RCT_NUMBER_CONVERTER(type, getter) \
 RCT_CUSTOM_CONVERTER(type, type, [[self NSNumber:json] getter])
 
-NSNumber *RCTEnumConverterImpl(const char *typeName, NSDictionary *values, NSNumber *defaultValue, id json);
-
 /**
  * This macro is used for creating converters for enum types.
  */
@@ -187,7 +190,7 @@ NSNumber *RCTEnumConverterImpl(const char *typeName, NSDictionary *values, NSNum
   dispatch_once(&onceToken, ^{                            \
     mapping = values;                                     \
   });                                                     \
-  NSNumber *converted = RCTEnumConverterImpl(#type, mapping, @(default), json); \
+  NSNumber *converted = RCTConverterEnumValue(#type, mapping, @(default), json); \
   return ((type(*)(id, SEL))objc_msgSend)(converted, @selector(getter)); \
 }