Add PromiseKit dependency

- Added PromiseKit dependency

Carthage/Checkouts/PromiseKit/Sources/PMKCallVariadicBlock.m

@@ -0,0 +1,120 @@
+#import "NSMethodSignatureForBlock.m"
+#import <Foundation/NSDictionary.h>
+#import <Foundation/NSException.h>
+#import "AnyPromise+Private.h"
+#import <Foundation/NSError.h>
+#import <dispatch/once.h>
+#import <string.h>
+
+#ifndef PMKLog
+#define PMKLog NSLog
+#endif
+
+@interface PMKArray : NSObject {
+@public
+    id objs[3];
+    NSUInteger count;
+} @end
+
+@implementation PMKArray
+
+- (id)objectAtIndexedSubscript:(NSUInteger)idx {
+    if (count <= idx) {
+        // this check is necessary due to lack of checks in `pmk_safely_call_block`
+        return nil;
+    }
+    return objs[idx];
+}
+
+@end
+
+id __PMKArrayWithCount(NSUInteger count, ...) {
+    PMKArray *this = [PMKArray new];
+    this->count = count;
+    va_list args;
+    va_start(args, count);
+    for (NSUInteger x = 0; x < count; ++x)
+        this->objs[x] = va_arg(args, id);
+    va_end(args);
+    return this;
+}
+
+
+static inline id _PMKCallVariadicBlock(id frock, id result) {
+    NSCAssert(frock, @"");
+
+    NSMethodSignature *sig = NSMethodSignatureForBlock(frock);
+    const NSUInteger nargs = sig.numberOfArguments;
+    const char rtype = sig.methodReturnType[0];
+
+    #define call_block_with_rtype(type) ({^type{ \
+        switch (nargs) { \
+            case 1: \
+                return ((type(^)(void))frock)(); \
+            case 2: { \
+                const id arg = [result class] == [PMKArray class] ? result[0] : result; \
+                return ((type(^)(id))frock)(arg); \
+            } \
+            case 3: { \
+                type (^block)(id, id) = frock; \
+                return [result class] == [PMKArray class] \
+                    ? block(result[0], result[1]) \
+                    : block(result, nil); \
+            } \
+            case 4: { \
+                type (^block)(id, id, id) = frock; \
+                return [result class] == [PMKArray class] \
+                    ? block(result[0], result[1], result[2]) \
+                    : block(result, nil, nil); \
+            } \
+            default: \
+                @throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"PromiseKit: The provided block’s argument count is unsupported." userInfo:nil]; \
+        }}();})
+
+    switch (rtype) {
+        case 'v':
+            call_block_with_rtype(void);
+            return nil;
+        case '@':
+            return call_block_with_rtype(id) ?: nil;
+        case '*': {
+            char *str = call_block_with_rtype(char *);
+            return str ? @(str) : nil;
+        }
+        case 'c': return @(call_block_with_rtype(char));
+        case 'i': return @(call_block_with_rtype(int));
+        case 's': return @(call_block_with_rtype(short));
+        case 'l': return @(call_block_with_rtype(long));
+        case 'q': return @(call_block_with_rtype(long long));
+        case 'C': return @(call_block_with_rtype(unsigned char));
+        case 'I': return @(call_block_with_rtype(unsigned int));
+        case 'S': return @(call_block_with_rtype(unsigned short));
+        case 'L': return @(call_block_with_rtype(unsigned long));
+        case 'Q': return @(call_block_with_rtype(unsigned long long));
+        case 'f': return @(call_block_with_rtype(float));
+        case 'd': return @(call_block_with_rtype(double));
+        case 'B': return @(call_block_with_rtype(_Bool));
+        case '^':
+            if (strcmp(sig.methodReturnType, "^v") == 0) {
+                call_block_with_rtype(void);
+                return nil;
+            }
+            // else fall through!
+        default:
+            @throw [NSException exceptionWithName:@"PromiseKit" reason:@"PromiseKit: Unsupported method signature." userInfo:nil];
+    }
+}
+
+static id PMKCallVariadicBlock(id frock, id result) {
+    @try {
+        return _PMKCallVariadicBlock(frock, result);
+    } @catch (id thrown) {
+        if ([thrown isKindOfClass:[NSString class]])
+            return thrown;
+        if ([thrown isKindOfClass:[NSError class]])
+            return thrown;
+
+        // we don’t catch objc exceptions: they are meant to crash your app
+        @throw thrown;
+    }
+}