Add support for Objective-C

Closes #600

Co-authored-by: Nick Moore <nick@pilotmoon.com>

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## 0.55 (unreleased)
 
+### Parsing
+
+Added support for Objective-C.
+
 ## 0.54 (released 7th January 2024)
 
 ### Parsing

build.rs

@@ -241,6 +241,11 @@ fn main() {
             src_dir: "vendored_parsers/tree-sitter-nix-src",
             extra_files: vec!["scanner.c"],
         },
+        TreeSitterParser {
+            name: "tree-sitter-objc",
+            src_dir: "vendored_parsers/tree-sitter-objc-src",
+            extra_files: vec![],
+        },
         TreeSitterParser {
             name: "tree-sitter-ocaml",
             src_dir: "vendored_parsers/tree-sitter-ocaml-src/ocaml/src",

manual/src/languages_supported.md

@@ -36,6 +36,7 @@ with `difft --list-languages`.
 | Lua             | [nvim-treesitter/tree-sitter-lua](https://github.com/nvim-treesitter/tree-sitter-lua)       |
 | Make            | [alemuller/tree-sitter-make](https://github.com/alemuller/tree-sitter-make)                 |
 | Nix             | [cstrahan/tree-sitter-nix](https://github.com/cstrahan/tree-sitter-nix)                     |
+| Objective-C     | [amaanq/tree-sitter-objc](https://github.com/amaanq/tree-sitter-objc)                       |
 | OCaml           | [tree-sitter/tree-sitter-ocaml](https://github.com/tree-sitter/tree-sitter-ocaml)           |
 | Perl            | [ganezdragon/tree-sitter-perl](https://github.com/ganezdragon/tree-sitter-perl)             |
 | PHP             | [tree-sitter/tree-sitter-php](https://github.com/tree-sitter/tree-sitter-php)               |

sample_files/compare.expected

@@ -163,6 +163,12 @@ e00b95a4cf3fa3edf994155d8656063f  -
 sample_files/nullable_before.kt sample_files/nullable_after.kt
 66da628a2c20e18059b8669aaa14a163  -
 
+sample_files/objc_header_before.h sample_files/objc_header_after.h
+f65feb21b25bb7f2ba31ee8f49977193  -
+
+sample_files/objc_module_before.m sample_files/objc_module_after.m
+c04cdebd2da077cf28b53307ad0a3b02  -
+
 sample_files/ocaml_before.ml sample_files/ocaml_after.ml
 2113c6c7959b8099f678d13953f7f44a  -
 

sample_files/objc_header_after.h

@@ -0,0 +1,32 @@
+//
+//  HttpServer.h after file
+//
+//  Created by Nicholas Moore on 20/09/2022.
+//  A line added to the header.
+//
+//  Added to difftastic test suite by the author.
+//  This source file is released by the author into the public domain.
+
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+typedef NSDictionary *_Nullable (^PopHttpRequestHandler)(NSURL *url,
+                                                         NSString *method,
+                                                         NSDictionary *headers,
+                                                         NSData *body);
+
+@interface PopHttpServer : NSObjectqq
+@property(readonly) uint16_t port; // comment
+@property(readonly) NSString *host;
+@property(readonly) NSString *lastError;
+@property(readonly, getter=isListening) BOOL listening;
+- (id)initWithPort:(uint16_t)port;
+- (BOOL)start;
+- (void)stop;
+- (void)registerHandler:(NSString *_Nonnull)pathPrefix
+                  block:(PopHttpRequestHandler)myblock
+                  added:(BOOL *_Nullable)added;
+@end
+
+NS_ASSUME_NONNULL_END

sample_files/objc_header_before.h

@@ -0,0 +1,25 @@
+//
+//  HttpServer.h
+//
+//  Created by Nicholas Moore on 20/09/2022.
+//
+//  Added to difftastic test suite by the author.
+//  This source file is released by the author into the public domain.
+
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+typedef NSDictionary *_Nullable(^PopHttpRequestHandler)(NSURL *url, NSString *method, NSDictionary *headers, NSData *body);
+
+@interface PopHttpServer : NSObject
+@property (readonly) uint16_t port;
+@property (readonly) NSString *lastError;
+@property (readonly, getter=isListening) BOOL listening;
+- (id)initWithPort:(uint16_t)port;
+- (BOOL)start;
+- (void)stop;
+- (void)registerHandler:(NSString *)pathPrefix block:(PopHttpRequestHandler)myblock;
+@end
+
+NS_ASSUME_NONNULL_END

sample_files/objc_module_after.m

@@ -0,0 +1,346 @@
+//
+//  HttpServer.m
+//  Simple HTTP server.
+//  by Nicholas Moore 2023
+//  inspired by http://www.cocoawithlove.com/2009/07/simple-extensible-http-server-in-cocoa.html
+//
+//  Added to difftastic test suite by the author.
+//  This source file is released by the author into the public domain.
+
+
+#import "PopHttpServer.h"
+#import "NMKit.h"
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+
+@interface PopHttpServer ()
+@property (readonly) CFSocketRef socket;
+@property (readonly) NSFileHandle *listenHandle;
+@property (readonly) NSMapTable<NSFileHandle *, NSObject *> *httpMessages;
+@property (readonly) NSMutableDictionary<NSString *, PopHttpRequestHandler> *handlers;
+@property NSString *lastError;
+@end
+
+const NSArray *expressions=@[@NO, @7, @(YES), @3.15, @(9), @-11, @"Goodbye"];
+
+@implementation PopHttpServer
+
+- (id)initWithPort:(uint16_t)port
+{
+    self=[super init];
+    if (self) {
+        self->_port=port;
+        self->_httpMessages=[NSMapTable weakToStrongObjectsMapTable];
+        self->_handlers=[NSMutableDictionary dictionary];
+    }
+    return self;
+}
+
+// warning: handlers will be called on a background thread!!
+- (void)registerHandler:(NSString *)pathPrefix block:(PopHttpRequestHandler)myblock
+{
+    [self.handlers setObject:myblock forKey:pathPrefix];
+}
+
+- (void)newHttpMessageForHandle:(NSFileHandle *const)connectionHandle
+{
+    [self.httpMessages setObject:CFBridgingRelease(CFHTTPMessageCreateEmpty(kCFAllocatorDefault, TRUE))
+                          forKey:connectionHandle];
+}
+
+- (BOOL)start
+{
+    NMLogFine(@"Attempting to start HTTP server on port %@", @(self.port));
+
+    // create socket
+    self->_socket = CFSocketCreate(kCFAllocatorDefault,
+        PF_INET, SOCK_STREAM, IPPROTO_TCP, 0, 6, NULL
+    );
+    if (!self.socket)
+    {
+        self.lastError=@"Unable to create socket";
+        return NO;
+    }
+
+    // set reuse flag
+    // "This lets us reclaim the port if it is open but idle (a common occurrence if we restart the program immediately after a crash or killing the application)."
+    const int reuse = true;
+    const int fileDescriptor = CFSocketGetNative(self.socket);
+    if (setsockopt(fileDescriptor, SOL_SOCKET, SO_REUSEADDR, (void *)&reuse, sizeof(int)) != 0)
+    {
+        self.lastError=@"Unable to set socket options.";
+        [self stop];
+        return NO;
+    }
+
+    // create address and port
+    struct sockaddr_in address;
+    memset(&address, 0, sizeof(address));
+    address.sin_len = sizeof(address);
+    address.sin_family = AF_INET;
+    address.sin_addr.s_addr = htonl(INADDR_ANY);
+    address.sin_port = htons(self.port);
+    NSData *const addressData = [NSData dataWithBytes:&address length:sizeof(address)];
+    if (CFSocketSetAddress(self.socket, (__bridge CFDataRef)addressData) != kCFSocketSuccess)
+    {
+        self.lastError=@"Unable to bind socket.";
+        [self stop]; return NO;
+    }
+
+    // add listener for connections
+    self->_listenHandle = [[NSFileHandle alloc]
+                           initWithFileDescriptor:fileDescriptor
+                           closeOnDealloc:YES];
+
+    // register for notifications
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(receiveIncomingConnectionNotification:)
+                                                 name:NSFileHandleConnectionAcceptedNotification
+                                               object:self.listenHandle];
+    [self.listenHandle acceptConnectionInBackgroundAndNotify];
+
+    NMLogFine(@"HTTP server started on port %@", @(self.port));
+    return YES;
+
+}
+
+// Undo everything that was done in start
+- (void)stop
+{
+    // close down all open connections
+    for (NSFileHandle *connectionHandle in [self.httpMessages keyEnumerator]) {
+        NMLogFine(@"Closing connection %@", connectionHandle);
+        [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                        name:NSFileHandleDataAvailableNotification
+                                                      object:connectionHandle];
+        [connectionHandle closeFile];
+    }
+
+    if (self.listenHandle)
+    {
+        [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                        name:NSFileHandleConnectionAcceptedNotification
+                                                      object:self.listenHandle];
+        [self.listenHandle closeFile];
+        self->_listenHandle=nil;
+    }
+
+    if (self.socket)
+    {
+        CFSocketInvalidate(self.socket);
+        CFRelease(self.socket);
+        self->_socket=nil;
+    }
+    NMLogFine(@"HTTP server on port %@ stopped", @(self.port));
+}
+
+- (BOOL)isListening
+{
+    return self.socket;
+}
+
+// notification sent by the listenHandle
+- (void)receiveIncomingConnectionNotification:(NSNotification *)notification
+{
+    NSFileHandle *const connectionHandle=[[notification userInfo] objectForKey:NSFileHandleNotificationFileHandleItem];
+    if(connectionHandle)
+    {
+        [self newHttpMessageForHandle:connectionHandle];
+        [[NSNotificationCenter defaultCenter] addObserver:self
+                                                 selector:@selector(receiveIncomingDataNotification:)
+                                                     name:NSFileHandleDataAvailableNotification
+                                                   object:connectionHandle];
+        [connectionHandle waitForDataInBackgroundAndNotify];
+    }
+    NMLogFine(@"Incoming connection %@", connectionHandle);
+
+    // accept another connection
+    [self.listenHandle acceptConnectionInBackgroundAndNotify];
+}
+
+typedef NS_ENUM(NSUInteger, DataOutcome) {
+    DataOutcomeContinue,
+    DataOutcomeClose,
+    DataOutcomeKeepAlive,
+    DataOutcomeUnknown,
+};
+- (void)receiveIncomingDataNotification:(NSNotification *)notification
+{
+    NSFileHandle *const connectionHandle=[notification object];
+
+    // get our stored partial http message for this connection
+    const CFHTTPMessageRef httpMessage=(__bridge CFHTTPMessageRef)[self.httpMessages objectForKey:connectionHandle];
+
+    // perform remaining processing in backgroumd thread
+    NMRunAsyncInBackground(^{
+        const DataOutcome outcome=[self processHttpDataForMessage:httpMessage
+                                                       connection:connectionHandle];
+        NMRunAsyncOnMainThread(^{
+            switch (outcome) {
+                case DataOutcomeClose:
+                    [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                                    name:NSFileHandleDataAvailableNotification
+                                                                  object:connectionHandle];
+                    [connectionHandle closeFile];
+                    NMLogFine(@"Closed connection %@; there are %@", connectionHandle, @(self.httpMessages.count));
+                    break;
+                case DataOutcomeKeepAlive:
+                    [self newHttpMessageForHandle:connectionHandle];
+                    NMLogFine(@"Ready for new message on connection %@; there are %@", connectionHandle, @(self.httpMessages.count));
+                    // here we deliberately fall through to the Continue case
+                case DataOutcomeContinue:
+                default:
+                    NMLogFine(@"Awaiting more data on connection %@", connectionHandle);
+                    [connectionHandle waitForDataInBackgroundAndNotify];
+                    break;
+            }
+        });
+    });
+}
+
+- (DataOutcome)processHttpDataForMessage:(CFHTTPMessageRef)httpMessage connection:(NSFileHandle *)connectionHandle
+{
+    // get the data (if any)
+    NSData *data=nil;
+    @try {
+        data=[connectionHandle availableData];
+    }
+    @catch(NSException *e) {
+        // Ignore the exception, it normally just means the client
+        // closed the connection from the other end.
+    }
+    NMLogFine(@"Data: %@ bytes received on connection %@", @(data.length), connectionHandle);
+
+    // close if EOF or error parsing into http message
+    if (!data.length || httpMessage ||
+        !CFHTTPMessageAppendBytes(httpMessage, data.bytes, data.length)) {
+        return DataOutcomeClose;
+    }
+
+    // continue if we don't have the full header yet
+    if (!CFHTTPMessageIsHeaderComplete(httpMessage)) {
+        return DataOutcomeContinue;
+    }
+
+    // get the Content-Length value
+    NSInteger contentLength=0;
+    CFStringRef contentLengthStr = CFHTTPMessageCopyHeaderFieldValue(httpMessage, CFSTR("Content-Length"));
+    if (contentLengthStr) {
+        contentLength = CFStringGetIntValue(contentLengthStr);
+        CFRelease(contentLengthStr);
+    }
+
+    // get the Connection header
+    BOOL closeWhenDone=NO;
+    CFStringRef connectionStr = CFHTTPMessageCopyHeaderFieldValue(httpMessage, CFSTR("Connection"));
+    if (connectionStr) {
+        closeWhenDone = (CFStringCompare(connectionStr, CFSTR("close"), kCFCompareCaseInsensitive)==kCFCompareEqualTo);
+        CFRelease(connectionStr);
+    }
+
+    // get received data length
+    NSInteger receivedLength;
+    CFDataRef bodyData = CFHTTPMessageCopyBody(httpMessage);
+    if (bodyData) {
+        receivedLength = CFDataGetLength(bodyData);
+        CFRelease(bodyData);
+    }
+
+    // check if full body is recieved
+    if (receivedLength>=contentLength) {
+        NMLogFine(@"Entire message received, responding on connection %@", connectionHandle);
+        [self respondToHttpMessage:httpMessage withConnection:connectionHandle];
+        return closeWhenDone?DataOutcomeClose:DataOutcomeKeepAlive;
+    } else {
+        return DataOutcomeContinue;
+    }
+}
+
+- (void)respondToHttpMessage:(CFHTTPMessageRef)httpMessage withConnection:(NSFileHandle *)connectionHandle
+{
+#ifdef DEBUG
+    NSMutableArray *const logMessage=[NSMutableArray array];
+    void(^log)(NSString *, ...) = ^(NSString *format, ...) {
+        va_list args;
+        va_start(args, format);
+        [logMessage addObject:[[NSString alloc] initWithFormat:format arguments:args]];
+        va_end(args);
+    };
+#endif
+
+    // get request info
+    NSURL *const url=CFBridgingRelease(CFHTTPMessageCopyRequestURL(httpMessage));
+    NSString *const method=CFBridgingRelease(CFHTTPMessageCopyRequestMethod(httpMessage));
+    NSDictionary *const headers=CFBridgingRelease(CFHTTPMessageCopyAllHeaderFields(httpMessage));
+    NSData *const body=CFBridgingRelease(CFHTTPMessageCopyBody(httpMessage));
+
+#ifdef DEBUG
+    log(@"%@ value is %@", method, url.absoluteURL);
+    log(@"Body: %@", body);
+#endif
+
+    // my very basic router
+    NSString *const firstPathPart=[[[url.path stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"/"]] componentsSeparatedByString:@"/"] safeFirstObject];
+    NSDictionary *res=nil;
+    PopHttpRequestHandler handler=[self.handlers objectForKey:firstPathPart];
+    if (handler) {
+#ifdef DEBUG
+        log(@"Route: %@", firstPathPart);
+#endif
+        res=handler(url, method, headers, body);
+    }
+#ifdef DEBUG
+    log(@"Response: %@", res);
+#endif
+
+    NMLogFine(@"%@", [logMessage componentsJoinedByString:@"\n"]);
+    // note: prevously was wrapping this in WarpToMain, but seems unnecessary
+    if (res) {
+        [self respondWithBody:res[@"body"] status:res[@"status"] contentType:res[@"contentType"] headers:res[@"headers"] handle:connectionHandle];
+    } else {
+        // redo
+    }
+}
+
+- (void)respondWithBody:(NSObject *)bodyObj status:(NSNumber *)status contentType:(NSString *)contentType headers:(NSDictionary<NSString *, NSString *> *)headers handle:(NSFileHandle *)connectionHandle
+{
+    NSData *bodyData=nil;
+    if ([bodyObj isKindOfClass:[NSString class]]) {
+        bodyData=[(NSString *)bodyObj dataUsingEncoding:NSUTF8StringEncoding];
+        contentType=[contentType stringByAppendingString:@"; charset=utf-8"];
+    }
+    else if ([bodyObj isKindOfClass:[NSData class]]) {
+        bodyData=(NSData *)bodyObj;
+    }
+    else {
+        NMLogError(@"Bad bodyObj: %@", bodyObj);
+        bodyData=[NSData data];
+    }
+
+    // create response message
+    CFHTTPMessageRef response=CFHTTPMessageCreateResponse(kCFAllocatorDefault, [status integerValue], NULL, kCFHTTPVersion1_1);
+    [headers enumerateKeysAndObjectsUsingBlock:^(NSString * _Nonnull key, NSString * _Nonnull val, BOOL * _Nonnull stop) {
+        CFHTTPMessageSetHeaderFieldValue(response, (__bridge CFStringRef)key, (__bridge CFStringRef)val);
+    }];
+    CFHTTPMessageSetHeaderFieldValue(response, CFSTR("content-type"), (__bridge CFStringRef)contentType);
+    CFHTTPMessageSetHeaderFieldValue(response, CFSTR("content-length"), (__bridge CFStringRef)[NSString stringWithFormat:@"%@", @(bodyData.length)]);
+    CFHTTPMessageSetBody(response, (__bridge CFDataRef)bodyData);
+    CFDataRef messageData = CFHTTPMessageCopySerializedMessage(response);
+    @try
+    {
+        [connectionHandle writeData:(__bridge NSData *)messageData];
+    }
+    @catch (NSException *exception)
+    {
+        // Ignore the exception, it normally just means the client
+        // closed the connection from the other end.
+    }
+    @finally
+    {
+        CFRelease(messageData);
+        CFRelease(response);
+    }
+}
+
+@end

sample_files/objc_module_before.m

@@ -0,0 +1,341 @@
+//
+//  HttpServer.m
+//  Simple HTTP server.
+//  by Nicholas Moore 2023
+//  inspired by http://www.cocoawithlove.com/2009/07/simple-extensible-http-server-in-cocoa.html
+//
+//  Added to difftastic test suite by the author.
+//  This source file is released by the author into the public domain.
+
+
+#import "PopHttpServer.h"
+#import "NMKit.h"
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+@interface PopHttpServer ()
+@property (readonly) CFSocketRef socket;
+@property (readonly) NSFileHandle *listenHandle;
+@property (readonly) NSMapTable<NSFileHandle *, id> *httpMessages;
+@property (readonly) NSMutableDictionary<NSString *, PopHttpRequestHandler> *handlers;
+@property NSString *lastError;
+@end
+
+const NSArray *expressions=@[@YES, @6, @(NO), @3.14, @(-9), @-10, @"Hello"];
+
+@implementation PopHttpServer
+
+- (id)initWithPort:(uint16_t)port
+{
+    self=[super init];
+    if (self) {
+        self->_port=port;
+        self->_httpMessages=[NSMapTable weakToStrongObjectsMapTable];
+        self->_handlers=[NSMutableDictionary dictionary];
+    }
+    return self;
+}
+
+// warning: handlers will be called on a background thread
+- (void)registerHandler:(NSString *)pathPrefix block:(PopHttpRequestHandler)myblock
+{
+    [self.handlers setObject:myblock forKey:pathPrefix];
+}
+
+- (void)newHttpMessageForHandle:(NSFileHandle *)connectionHandle
+{
+    [self.httpMessages setObject:CFBridgingRelease(CFHTTPMessageCreateEmpty(kCFAllocatorDefault, TRUE)) forKey:connectionHandle];
+}
+
+- (BOOL)start
+{
+    NMLogFine(@"Attempting to start HTTP server on port %@", @(self.port));
+
+    // create socket
+    self->_socket = CFSocketCreate(kCFAllocatorDefault, PF_INET, SOCK_STREAM, IPPROTO_TCP, 0, NULL, NULL);
+    if (!self.socket)
+    {
+        self.lastError=@"Unable to create socket";
+        return NO;
+    }
+
+    // set reuse flag
+    // "This lets us reclaim the port if it is open but idle (a common occurrence if we restart the program immediately after a crash or killing the application)."
+    const int reuse = true;
+    const int fileDescriptor = CFSocketGetNative(self.socket);
+    if (setsockopt(fileDescriptor, SOL_SOCKET, SO_REUSEADDR, (void *)&reuse, sizeof(int)) != 0)
+    {
+        self.lastError=@"Unable to set socket options.";
+        [self stop];
+        return NO;
+    }
+
+    // create address and port
+    struct sockaddr_in address;
+    memset(&address, 0, sizeof(address));
+    address.sin_len = sizeof(address);
+    address.sin_family = AF_INET;
+    address.sin_addr.s_addr = htonl(INADDR_ANY);
+    address.sin_port = htons(self.port);
+    NSData *const addressData = [NSData dataWithBytes:&address length:sizeof(address)];
+    if (CFSocketSetAddress(self.socket, (__bridge CFDataRef)addressData) != kCFSocketSuccess)
+    {
+        self.lastError=@"Unable to bind socket to address.";
+        [self stop];
+        return NO;
+    }
+
+    // add listener for connections
+    self->_listenHandle = [[NSFileHandle alloc]
+                           initWithFileDescriptor:fileDescriptor
+                           closeOnDealloc:YES];
+
+    // register for notifications
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(receiveIncomingConnectionNotification:)
+                                                 name:NSFileHandleConnectionAcceptedNotification
+                                               object:self.listenHandle];
+    [self.listenHandle acceptConnectionInBackgroundAndNotify];
+
+    NMLogFine(@"HTTP server started on port %@", @(self.port));
+    return YES;
+
+}
+
+// Undo everything in start
+- (void)stop
+{
+    // close down all open connections
+    for (NSFileHandle *connectionHandle in [self.httpMessages keyEnumerator]) {
+        NMLogFine(@"Closing connection %@", connectionHandle);
+        [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                        name:NSFileHandleDataAvailableNotification
+                                                      object:connectionHandle];
+        [connectionHandle closeFile];
+    }
+
+    if (self.listenHandle)
+    {
+        [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                        name:NSFileHandleConnectionAcceptedNotification
+                                                      object:self.listenHandle];
+        [self.listenHandle closeFile];
+        self->_listenHandle=nil;
+    }
+
+    if (self.socket)
+    {
+        CFSocketInvalidate(self.socket);
+        CFRelease(self.socket);
+        self->_socket=nil;
+    }
+    NMLogFine(@"HTTP server on port %@ stopped", @(self.port));
+}
+
+- (BOOL)isListening
+{
+    return self.socket;
+}
+
+// notification sent by the listenHandle
+- (void)receiveIncomingConnectionNotification:(NSNotification *)notification
+{
+    NSFileHandle *const connectionHandle=[[notification userInfo] objectForKey:NSFileHandleNotificationFileHandleItem];
+    if(connectionHandle)
+    {
+        [self newHttpMessageForHandle:connectionHandle];
+        [[NSNotificationCenter defaultCenter] addObserver:self
+                                                 selector:@selector(receiveIncomingDataNotification:)
+                                                     name:NSFileHandleDataAvailableNotification
+                                                   object:connectionHandle];
+        [connectionHandle waitForDataInBackgroundAndNotify];
+    }
+    NMLogFine(@"Incoming connection %@", connectionHandle);
+    // accept another connection
+    [self.listenHandle acceptConnectionInBackgroundAndNotify];
+}
+
+typedef NS_ENUM(NSUInteger, DataOutcome) {
+    DataOutcomeContinue,
+    DataOutcomeClose,
+    DataOutcomeKeepAlive,
+};
+- (void)receiveIncomingDataNotification:(NSNotification *)notification
+{
+    NSFileHandle *const connectionHandle=[notification object];
+
+    // get our stored partial http message for this connection
+    const CFHTTPMessageRef httpMessage=(__bridge CFHTTPMessageRef)[self.httpMessages objectForKey:connectionHandle];
+
+    // perform remaining processing in backgroumd thread
+    NMRunAsyncInBackground(^{
+        const DataOutcome outcome=[self processHttpDataForMessage:httpMessage connection:connectionHandle];
+        NMRunAsyncOnMainThread(^{
+            switch (outcome) {
+                case DataOutcomeClose:
+                    [[NSNotificationCenter defaultCenter] removeObserver:self
+                                                                    name:NSFileHandleDataAvailableNotification
+                                                                  object:connectionHandle];
+                    [connectionHandle closeFile];
+                    NMLogFine(@"Closed connection %@; there are %@", connectionHandle, @(self.httpMessages.count));
+                    break;
+                case DataOutcomeKeepAlive:
+                    [self newHttpMessageForHandle:connectionHandle];
+                    NMLogFine(@"Ready for new message on connection %@; there are %@", connectionHandle, @(self.httpMessages.count));
+                    // here we deliberately fall through to the Continue case
+                case DataOutcomeContinue:
+                default:
+                    NMLogFine(@"Awaiting more data on connection %@", connectionHandle);
+                    [connectionHandle waitForDataInBackgroundAndNotify];
+                    break;
+            }
+        });
+    });
+}
+
+- (DataOutcome)processHttpDataForMessage:(CFHTTPMessageRef)httpMessage connection:(NSFileHandle *)connectionHandle
+{
+    // get the data (if any)
+    NSData *data=nil;
+    @try {
+        data=[connectionHandle availableData];
+    }
+    @catch(NSException *e) {
+        // Ignore the exception, it normally just means the client
+        // closed the connection from the other end.
+    }
+    NMLogFine(@"Data: %@ bytes received on connection %@", @(data.length), connectionHandle);
+
+    // close if EOF or error parsing into http message
+    if (!data.length ||
+        !httpMessage ||
+        !CFHTTPMessageAppendBytes(httpMessage, data.bytes, data.length)) {
+        return DataOutcomeClose;
+    }
+
+    // continue if we don't have the full header yet
+    if (!CFHTTPMessageIsHeaderComplete(httpMessage)) {
+        return DataOutcomeContinue;
+    }
+
+    // get the Content-Length value
+    NSInteger contentLength=0;
+    CFStringRef contentLengthStr = CFHTTPMessageCopyHeaderFieldValue(httpMessage, CFSTR("Content-Length"));
+    if (contentLengthStr) {
+        contentLength = CFStringGetIntValue(contentLengthStr);
+        CFRelease(contentLengthStr);
+    }
+
+    // get the Connection header
+    BOOL closeWhenDone=NO;
+    CFStringRef connectionStr = CFHTTPMessageCopyHeaderFieldValue(httpMessage, CFSTR("Connection"));
+    if (connectionStr) {
+        closeWhenDone = (CFStringCompare(connectionStr, CFSTR("close"), kCFCompareCaseInsensitive)==kCFCompareEqualTo);
+        CFRelease(connectionStr);
+    }
+
+    // get received data length
+    NSInteger receivedLength=0;
+    CFDataRef bodyData = CFHTTPMessageCopyBody(httpMessage);
+    if (bodyData) {
+        receivedLength = CFDataGetLength(bodyData);
+        CFRelease(bodyData);
+    }
+
+    // check if full body is recieved
+    if (receivedLength>=contentLength) {
+        NMLogFine(@"Entire message received, responding on connection %@", connectionHandle);
+        [self respondToHttpMessage:httpMessage withConnection:connectionHandle];
+        return closeWhenDone?DataOutcomeClose:DataOutcomeKeepAlive;
+    } else {
+        return DataOutcomeContinue;
+    }
+}
+
+- (void)respondToHttpMessage:(CFHTTPMessageRef)httpMessage withConnection:(NSFileHandle *)connectionHandle
+{
+#ifdef DEBUG
+    NSMutableArray *const logMessage=[NSMutableArray array];
+    void(^log)(NSString *, ...) = ^(NSString *format, ...) {
+        va_list args;
+        va_start(args, format);
+        [logMessage addObject:[[NSString alloc] initWithFormat:format arguments:args]];
+        va_end(args);
+    };
+#endif
+
+    // get request info
+    NSURL *const url=CFBridgingRelease(CFHTTPMessageCopyRequestURL(httpMessage));
+    NSString *const method=CFBridgingRelease(CFHTTPMessageCopyRequestMethod(httpMessage));
+    NSDictionary *const headers=CFBridgingRelease(CFHTTPMessageCopyAllHeaderFields(httpMessage));
+    NSData *const body=CFBridgingRelease(CFHTTPMessageCopyBody(httpMessage));
+
+#ifdef DEBUG
+    log(@"%@ %@", method, url.absoluteURL);
+    log(@"Body: %@", body);
+#endif
+
+    // my very basic router
+    NSString *const firstPathPart=[[[url.path stringByTrimmingCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"/"]] componentsSeparatedByString:@"/"] safeFirstObject];
+    NSDictionary *res=nil;
+    PopHttpRequestHandler handler=[self.handlers objectForKey:firstPathPart];
+    if (handler) {
+#ifdef DEBUG
+        log(@"Route: %@", firstPathPart);
+#endif
+        res=handler(url, method, headers, body);
+    }
+#ifdef DEBUG
+    log(@"Response: %@", res);
+#endif
+
+    NMLogFine(@"%@", [logMessage componentsJoinedByString:@"\n"]);
+    // note: prevously was wrapping this in WarpToMain, but seems unnecessary
+    if (res) {
+        [self respondWithBody:res[@"body"] status:res[@"status"] contentType:res[@"contentType"] headers:res[@"headers"] handle:connectionHandle];
+    } else {
+        [self respondWithBody:@"Not found\n" status:@(404) contentType:@"text/plain" headers:@{} handle:connectionHandle];
+    }
+}
+
+- (void)respondWithBody:(NSObject *)bodyObj status:(NSNumber *)status contentType:(NSString *)contentType headers:(NSDictionary<NSString *, NSString *> *)headers handle:(NSFileHandle *)connectionHandle
+{
+    NSData *bodyData=nil;
+    if ([bodyObj isKindOfClass:[NSString class]]) {
+        bodyData=[(NSString *)bodyObj dataUsingEncoding:NSUTF8StringEncoding];
+        contentType=[contentType stringByAppendingString:@"; charset=utf-8"];
+    }
+    else if ([bodyObj isKindOfClass:[NSData class]]) {
+        bodyData=(NSData *)bodyObj;
+    }
+    else {
+        NMLogError(@"Bad bodyObj: %@", bodyObj);
+        bodyData=[NSData data];
+    }
+
+    // create response message
+    CFHTTPMessageRef response=CFHTTPMessageCreateResponse(kCFAllocatorDefault, [status integerValue], NULL, kCFHTTPVersion1_1);
+    [headers enumerateKeysAndObjectsUsingBlock:^(NSString * _Nonnull key, NSString * _Nonnull val, BOOL * _Nonnull stop) {
+        CFHTTPMessageSetHeaderFieldValue(response, (__bridge CFStringRef)key, (__bridge CFStringRef)val);
+    }];
+    CFHTTPMessageSetHeaderFieldValue(response, CFSTR("Content-Type"), (__bridge CFStringRef)contentType);
+    CFHTTPMessageSetHeaderFieldValue(response, CFSTR("Content-Length"), (__bridge CFStringRef)[NSString stringWithFormat:@"%@", @(bodyData.length)]);
+    CFHTTPMessageSetBody(response, (__bridge CFDataRef)bodyData);
+    CFDataRef messageData = CFHTTPMessageCopySerializedMessage(response);
+    @try
+    {
+        [connectionHandle writeData:(__bridge NSData *)messageData];
+    }
+    @catch (NSException *exception)
+    {
+        // Ignore the exception, it normally just means the client
+        // closed the connection from the other end.
+    }
+    @finally
+    {
+        CFRelease(messageData);
+        CFRelease(response);
+    }
+}
+
+@end

src/parse/guess_language.rs

@@ -53,6 +53,7 @@ pub(crate) enum Language {
     Make,
     Newick,
     Nix,
+    ObjC,
     OCaml,
     OCamlInterface,
     Pascal,
@@ -140,6 +141,7 @@ pub(crate) fn language_name(language: Language) -> &'static str {
         Make => "Make",
         Newick => "Newick",
         Nix => "Nix",
+        ObjC => "Objective-C",
         OCaml => "OCaml",
         OCamlInterface => "OCaml Interface",
         Pascal => "Pascal",
@@ -317,6 +319,7 @@ pub(crate) fn language_globs(language: Language) -> Vec<glob::Pattern> {
         ],
         Newick => &["*.nhx", "*.nwk", "*.nh"],
         Nix => &["*.nix"],
+        ObjC => &["*.m"],
         OCaml => &["*.ml"],
         OCamlInterface => &["*.mli"],
         Pascal => &["*.pas", "*.dfm", "*.dpr", "*.lpr", "*.pascal"],
@@ -391,6 +394,24 @@ fn looks_like_hacklang(path: &Path, src: &str) -> bool {
     false
 }
 
+/// Use a heuristic to determine if a '.h' file looks like Objective-C.
+/// We look for a line starting with '#import', '@interface' or '@protocol'
+/// near the top of the file.  These keywords are not valid C or C++, so this
+/// should not produce false positives.
+fn looks_like_objc(path: &Path, src: &str) -> bool {
+    if let Some(extension) = path.extension() {
+        if extension == "h" {
+            return src.lines().take(100).any(|line| {
+                ["#import", "@interface", "@protocol"]
+                    .iter()
+                    .any(|keyword| line.starts_with(keyword))
+            });
+        }
+    }
+
+    false
+}
+
 pub(crate) fn guess(
     path: &Path,
     src: &str,
@@ -421,6 +442,9 @@ pub(crate) fn guess(
     if looks_like_hacklang(path, src) {
         return Some(Language::Hack);
     }
+    if looks_like_objc(path, src) {
+        return Some(Language::ObjC);
+    }
     if let Some(lang) = from_glob(path) {
         return Some(lang);
     }
@@ -468,6 +492,7 @@ fn from_emacs_mode_header(src: &str) -> Option<Language> {
             "js" | "js2" => Some(JavaScript),
             "lisp" => Some(CommonLisp),
             "nxml" => Some(Xml),
+            "objc" => Some(ObjC),
             "perl" => Some(Perl),
             "python" => Some(Python),
             "racket" => Some(Racket),

src/parse/tree_sitter_parser.rs

@@ -94,6 +94,7 @@ extern "C" {
     fn tree_sitter_make() -> ts::Language;
     fn tree_sitter_newick() -> ts::Language;
     fn tree_sitter_nix() -> ts::Language;
+    fn tree_sitter_objc() -> ts::Language;
     fn tree_sitter_ocaml() -> ts::Language;
     fn tree_sitter_ocaml_interface() -> ts::Language;
     fn tree_sitter_pascal() -> ts::Language;
@@ -739,6 +740,27 @@ pub(crate) fn from_language(language: guess::Language) -> TreeSitterConfig {
                 sub_languages: vec![],
             }
         }
+        ObjC => {
+            let language = unsafe { tree_sitter_objc() };
+            TreeSitterConfig {
+                language,
+                atom_nodes: vec!["string_literal"].into_iter().collect(),
+                delimiter_tokens: vec![
+                    ("(", ")"),
+                    ("{", "}"),
+                    ("[", "]"),
+                    ("@(", ")"),
+                    ("@{", "}"),
+                    ("@[", "]"),
+                ],
+                highlight_query: ts::Query::new(
+                    language,
+                    include_str!("../../vendored_parsers/highlights/objc.scm"),
+                )
+                .unwrap(),
+                sub_languages: vec![],
+            }
+        }
         OCaml => {
             let language = unsafe { tree_sitter_ocaml() };
             TreeSitterConfig {

vendored_parsers/highlights/objc.scm

@@ -0,0 +1 @@
+../tree-sitter-objc/queries/highlights.scm

vendored_parsers/tree-sitter-objc-src

@@ -0,0 +1 @@
+tree-sitter-objc/src