Expecta matcher for collection containing an instance of a given class

EXPMatchers+containObject.h

//
//  EXPMatchers+containObject.h
//  Created by Jonathan Crooke on 28/01/2014.
//

#import "Expecta.h"

/**
 *  Match a collection that contains at least one object that is
 *  an instance of expected
 */
EXPMatcherInterface(containInstanceOf, (Class expected));

/**
 *  Match a collection that contains at least one object that is
 *  a kind of expected
 */
EXPMatcherInterface(containKindOf, (Class expected));

// TODO: master matcher that uses a block?

EXPMatchers+containObject.m

//
//  EXPMatchers+containObject.m
//  Created by Jonathan Crooke on 28/01/2014.
//

EXPMatcherImplementationBegin(containInstanceOf, (Class expected)) {
  BOOL actualIsNil = (actual == nil);
  BOOL expectedIsNil = (expected == nil);
  BOOL actualIsCompatible = (!actualIsNil &&
                             ([actual isKindOfClass:[NSString class]] ||
                              [actual respondsToSelector:@selector(count)]));
  __block NSArray *matches = nil;

  prerequisite(^BOOL{
    return actualIsCompatible && !expectedIsNil;
  });

  match(^BOOL{
    if (actualIsCompatible) {
      matches = [actual filteredArrayUsingPredicate:
                 [NSPredicate predicateWithBlock:^BOOL(id evaluatedObject,
                                                       NSDictionary *bindings)
                  {
                    return [evaluatedObject class] == expected;
                  }]];
      return !!matches.count;
    }
    return NO;
  });

  NSString*(^incompatibilityMessage)(void) = ^NSString* (void) {
    if(!actualIsCompatible)
      return [NSString stringWithFormat:
              @"%@ is not an instance of NSString, "
              "NSArray, NSSet, NSOrderedSet, or NSDictionary",
              EXPDescribeObject(actual)];
    if(actualIsNil)
      return @"the actual value is nil/null";
    if(expectedIsNil)
      return @"the expected value is nil/null";
    return nil;
  };

  failureMessageForTo(^NSString *{
    return incompatibilityMessage() ?:
    [NSString stringWithFormat:
     @"expected: collection containing at least one instance of %@, "
     "got: collection containing %@",
     [expected class], actual];
  });

  failureMessageForNotTo(^NSString *{
    return incompatibilityMessage() ?:
    [NSString stringWithFormat:
     @"expected: collection not containing any instances of %@, "
     "got: collection containing %@, %d instance(s) of %@",
     [expected class], matches, matches.count, [expected class]];
  });
}
EXPMatcherImplementationEnd

#pragma mark -

EXPMatcherImplementationBegin(containKindOf, (Class expected)) {
  BOOL actualIsNil = (actual == nil);
  BOOL expectedIsNil = (expected == nil);
  BOOL actualIsCompatible = (!actualIsNil &&
                             ([actual isKindOfClass:[NSString class]] ||
                              [actual respondsToSelector:@selector(count)]));
  __block NSArray *matches = nil;

  prerequisite(^BOOL{
    return actualIsCompatible && !expectedIsNil;
  });

  match(^BOOL{
    if (actualIsCompatible) {
      matches = [actual filteredArrayUsingPredicate:
                 [NSPredicate predicateWithBlock:^BOOL(id evaluatedObject,
                                                       NSDictionary *bindings)
                  {
                    return [evaluatedObject isKindOfClass:[expected class]];
                  }]];
      return !!matches.count;
    }
    return NO;
  });

  NSString*(^incompatibilityMessage)(void) = ^NSString* (void) {
    if(!actualIsCompatible)
      return [NSString stringWithFormat:
              @"%@ is not an instance of NSString, "
              "NSArray, NSSet, NSOrderedSet, or NSDictionary",
              EXPDescribeObject(actual)];
    if(actualIsNil)
      return @"the actual value is nil/null";
    if(expectedIsNil)
      return @"the expected value is nil/null";
    return nil;
  };

  failureMessageForTo(^NSString *{
    return incompatibilityMessage() ?:
    [NSString stringWithFormat:
     @"expected: collection containing at least one object that's a kind of %@, "
     "got: collection containing %@",
     [expected class], actual];
  });

  failureMessageForNotTo(^NSString *{
    return incompatibilityMessage() ?:
    [NSString stringWithFormat:
     @"expected: collection not containing any objects that are a kind of %@, "
     "got: collection containing %@, %d instance(s) of %@",
     [expected class], matches, matches.count, [expected class]];
  });
}
EXPMatcherImplementationEnd

Copy & paste 😞, TODO: DRY out, and block matcher