Generates a random string of real US English words using UITextChecker completions

random-string.m

@implementation NSArray (DHRandom)

- (nullable id)dh_random {
    if (self.count == 0) {
        return nil;
    }
    return self[arc4random_uniform((u_int32_t)self.count)];
}

@end

@implementation UITextChecker (DHNonnull)

- (nonnull NSArray<NSString *> *)dh_completionsForPartialWordRange:(NSRange)range inString:(NSString *)string language:(NSString *)language {
    return (NSArray *)([self completionsForPartialWordRange:range inString:string language:language] ?: @[]);
}

@end

NSString *DHRandomText(void) {
    id checker = [[UITextChecker alloc] init];

    id startingCharacters = @[@"q", @"w", @"e", @"r", @"t", @"y", @"u", @"i", @"o", @"p", @"l", @"k", @"j", @"h", @"g", @"f", @"d", @"s", @"a", @"z", @"x", @"c", @"v", @"b", @"n", @"m"];

    NSMutableArray<NSString *> *randomWords = [NSMutableArray array];

    while (arc4random_uniform(30) != 0) {
        NSString *startingCharacter = [startingCharacters dh_random];
        NSString *randomWord = [[checker dh_completionsForPartialWordRange:NSMakeRange(0, startingCharacter.length) inString:startingCharacter language:@"en_US"] dh_random];
        if (randomWord) {
            [randomWords addObject:randomWord];
        }
    }

    return [randomWords componentsJoinedByString:@" "];
}