Lorem ipsum dolor sit a met, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation.
Clojure.spec provides seamless integration with clojure.test.check’s generators. Write a spec, get a functioning generator, and you can use that generator in a REPL as you’re developing, or in a generative test.
If you like, you can follow along by evaluating the forms (in order of appearance – some redef vars that are defd earlier in the namespace) in codebreaker.clj.
Image source: Stack Overflow
Problem
We want a function that accepts a secret code and a guess, and returns a score for that guess. Codes are made of 4 to 6 colored pegs, selected from six colors: [r]edr [y]ellow, [g]reen, [c][/c]yan, [b]lack, and [w]hite. The score is based on the number of pegs in the guess that match the secret code. A peg in the guess that matches the color of the peg in the same position in the secret code is considered an exact match, and a peg that matches a peg in a different position in the secret code is considered a loose match.
For example, if the secret code is [:r :y :g :c] and the guess is [:c :y :g :b], the score would be {:codebreaker/exact-matches 2 :codebreaker/loose-matches 1} because :y and :g appear in the same positions and :c appears in a different position.
We want to invoke this fn with two codes and get back a map like the one above, e.g.
1
2
3
4
5
6
7
8
publicclassMyApplicationextendsApplication{
@Override
publicvoidonCreate(){
super.onCreate();
Realm.init(this);
// Other initializers
}
}
Properties and property-based testing
In property-based testing, we make assertions about properties of a function and provide test data generators. The testing tool then generates test data, applies the function to it, and invokes the assertions. Properties are more general than examples in example based tests. For example, rather than writing a test that expresses the example above and asserts that the resulting map looks exactly like the one above, we’d write expressions that express more general properties like:
The return value should be a map with the two keys :codebreaker/exact-matches and :codebreaker/loose-matches
the values should be natural (i.e. non-negative) integers
the sum of the values should be >= 0
the sum of the values should be <= the number of pegs in the secret code
We’ll express all of these properties using clojure.spec, and we’re also going to describe the arguments to the function using the same tooling. This is one way in clojure.spec departs from other property-based testing tools.
Properties and property-based testing
In property-based testing, we make assertions about properties of a function and provide test data generators. The testing tool then generates test data, applies the function to it, and invokes the assertions. Properties are more general than examples in example based tests. For example, rather than writing a test that expresses the example above and asserts that the resulting map looks exactly like the one above, we’d write expressions that express more general properties like:
The return value should be a map with the two keys :codebreaker/exact-matches and :codebreaker/loose-matches
the values should be natural (i.e. non-negative) integers
the sum of the values should be >= 0
the sum of the values should be <= the number of pegs in the secret code
We’ll express all of these properties using clojure.spec, and we’re also going to describe the arguments to the function using the same tooling. This is one way in clojure.spec departs from other property-based testing tools.
Properties and property-based testing
In property-based testing, we make assertions about properties of a function and provide test data generators. The testing tool then generates test data, applies the function to it, and invokes the assertions. Properties are more general than examples in example based tests. For example, rather than writing a test that expresses the example above and asserts that the resulting map looks exactly like the one above, we’d write expressions that express more general properties like:
You can easily scan these examples visually and validate that they’re all producing the correct result for :codebreaker/exact-matches.
Н4 Body Subheading
We’ll express all of these properties using clojure.spec, and we’re also going to describe the arguments to the function using the same tooling. This is one way in clojure.spec departs from other property-based testing tools.
:args
We have a few more questions to answer, but that’s enough to get started, which we’ll do with a function spec. We’ll start with just the spec for the arguments, and a couple of supporting definitions.
1
2
3
4
5
6
7
8
9
10
11
12
13
// Authenticating the User
User.authenticate(with:.google("google token"),
server:URL(string:"https://realm.example.com:9443")){user,error in
iflet user=user{
// Opening a remote Realm
let realmURL=URL(string:"realm://realm.example.com:9080/~/userRealm")!
let config=Realm.Configuration(syncConfiguration:(user,realmURL))
let realm=try!Realm(configuration:config)
// Any changes made to this Realm will be synced across all devices!
}elseiflet error=error{
// handle error
}
}
Experience report
The exact match calculation is easy to imagine: we need to compare each peg in the guess to the peg in the same position in the secret:
You can easily scan these examples visually and validate that they’re all producing the correct result for :codebreaker/exact-matches.
I’ve been using TDD in some form or another for many years, and when clojure.spec appeared I was curious to see how it would fit into or change my approach. I won’t go as far as to say that this post represents “my approach” as that is still evolving in light of the presence of spec, but there are clear similarities to and differences from TDD in this example.
Like TDD, there is a tight feedback loop: write a spec and exercise it right away, all before any implementation code. The spec itself is not a test, but it is a reusable source for generated sample data that we can use in an interactive REPL session and in a repeatable test.
Like TDD, I did some refactoring as I discovered opportunities to improve the code. Sometimes I used visual inspection of the result of exercising specs and sometimes I used test.check to cast a wider net.
Unlike TDD, I didn’t go through a consistent cycle of watching a test fail and then making it pass, and then refactoring (red/green/refactor). You can use these tools for that cycle, but generative tests are, by design, more coarse than example based tests, so it might be more of a challenge to keep that very granular cycle consistent. Perhaps a subject for another post (perhaps written by you!).
Prediksi Togel Totojitu Online Singapore Di Garuda4D – Di pita Anda dapat memutuskan opsi apa togel totojitu yang akan dibuat tetapi semua ambang di atas meja garuda4d sebagai penyelenggara togel sama dengan rumah sehingga Anda hanya memiliki satu keputusan tentang apa yang harus dilakukan. Anda ingin uang Anda terbuan…
Prediksi Togel Hongkong Saat Ini Oleh Agen PediaTogel.com, berikut ini sebuah contoh jika Anda telah menyiapkan sejumlah besar uang, misalnya maka pilih taruhan yang ingin Anda mainkan apakah ekornya aneh ekor lurus ayam besar atau ayam kecil. Jelas bahwa Anda harus mengambil angka pada titik ujung yaitu ekor sebagai p…
Ingin sekali menang togel King4D online pasti sangat untung banget dan semua itu meungkin saja bisa anda dapatkan karena sebagai agen resmi akan kami berikan link alternatif yaitu Senior4D.com unuk anda yang ingin merasakan kemenangan togel tentu tidak bro sepertinya merek itu bukan posisi utama raja egret, Anda hanya …