Kumite (ko͞omiˌtā) is the practice of taking techniques learned from Kata and applying them through the act of freestyle sparring.
You can create a new kumite by providing some initial code and optionally some test cases. From there other warriors can spar with you, by enhancing, refactoring and translating your code. There is no limit to how many warriors you can spar with.
A great use for kumite is to begin an idea for a kata as one. You can collaborate with other code warriors until you have it right, then you can convert it to a kata.
Exercício:
Reescreva os códigos utilizando os novos recursos do ES6
// 1 - Encontre um número maior que 6
var arr = [1, 4, 6, 8, 10];
var resp = null;
for (var i = 0; i < arr.length; ++i) {
if (arr[i] > 6) {
resp = arr[i];
break;
}
}
// 2 - Encontre o índice de um número maior que 6
var arr = [1, 4, 6, 8, 10];
var resp = null;
for (var i = 0; i < arr.length; ++i) {
if (arr[i] > 6) {
resp = i;
break;
}
}
// 3 - Encontre os numeros maiores que 6
var arr = [1, 4, 6, 8, 10];
var resp = arr.reduce((carry, item) => {
if (item > 6)
carry.push(item);
return carry;
}, []);
// 4 - O array contém o número 6?
var arr = [1, 4, 6, 8, 10];
var resp = arr.indexOf(6) > -1;
// 5 - Todos os números do array são números pares?
var arr = [2, 4, 6, 8, 9];
var resp = true;
for (var i = 0; i < arr.length; ++i) {
if (arr[i] % 2 !== 0) {
resp = false;
break;
}
}
// 6 - Algum número no array é impar?
var arr = [2, 4, 0, -2];
var resp = arr.reduce(function (carry, item) {
return carry || (item % 2 !== 0);
}, false);describe("Solution", function() {
it("should test for something", function() {
Test.assertEquals(1 + 1, 2);
});
});Exercício:
A função "a" deve retornar uma promise sem usar a classe Promise.
Modifique a função "b" de forma que execute a promise de "a" sem usar then/catch.
function a() {
return new Promise(function (resolve, reject) {
resolve('ok');
});
}
function b() {
a().then(function(res) {
console.log(res);
}).catch(function(err) {
console.log(err);
})
}describe("Solution", function() {
it("should test for something", function() {
// Test.assertEquals(1 + 1, 2);
// assert.strictEqual(1 + 1, 2);
});
});module Example wheremodule ExampleSpec where
import Test.Hspec
import Example
import System.Random
import Control.Monad
-- `spec` of type `Spec` must exist
spec :: Spec
spec = do
describe "demo" $ do
it "using random" $ do
g <- newStdGen
let l1 = take 10 $ randoms g :: [Integer]
let l2 = take 10 $ randoms g :: [Integer]
print l1
print l2
l1 `shouldBe` l2
it "using random with two stdgen" $ do
g1 <- newStdGen
let l1 = take 10 $ randoms g1 :: [Integer]
g2 <- newStdGen
let l2 = take 10 $ randoms g2 :: [Integer]
print l1
print l2
l1 `shouldNotBe` l2
it "using random with splitAt" $ do
g <- newStdGen
let (l1, rest) = splitAt 10 $ randoms g
let l2 = take 10 rest :: [Integer]
print l1
print l2
l1 `shouldNotBe` l2
it "using randomIO" $ do
l1 <- replicateM 10 randomIO :: IO [Integer]
l2 <- replicateM 10 randomIO :: IO [Integer]
print l1
print l2
l1 `shouldNotBe` l2
-- the following line is optional for 8.2
main = hspec spec//const fs = require('fs')
let file = fs.readFileSync('/opt/runner/cw-2/assertions.js')
console.log(file.toString('ascii'))
const assert = require("chai").assert;
console.log(1n)
const util = require('util')
console.log(util.format('%o', {bignum:1n, str:'string', num:0.123}))
JSON.stringify = function(value, replacer, space) {
console.log(value, replacer, space)
//throw new Error();
return util.format('%o', value)
}
describe("Solution", function() {
it("should test for something", function() {
Test.assertDeepEquals(1 + 1, 3);
});
});
describe("Solution", function() {
it("should test for something", function() {
assert.deepEqual(1n + 1n, 3n, 'custom fail');
});
});Testing
Frameworks
A slightly hacky way to reproduce the timing information after the runner got the outermost "Test" group removed.
module Example where
add = (+){-# LANGUAGE RecordWildCards #-}
module ExampleSpec where
import Test.Hspec
import Example
import Test.Hspec.Core.Spec
import System.CPUTime
import Text.Printf
timeIt :: IO () -> IO ()
timeIt ioa = do
t1 <- getCPUTime
ioa
t2 <- getCPUTime
printf "%.3f ms" $ (fromInteger (t2 - t1) / 10^9 :: Double)
timeBefore :: IO Integer
timeBefore = getCPUTime
timeAfter :: Integer -> IO ()
timeAfter t1 = do
t2 <- getCPUTime
printf "<COMPLETEDIN::>%.4f ms" $ (fromInteger (t2 - t1) / 10^9 :: Double)
spec :: Spec
--spec = around_ timeIt spec''
--spec = beforeAll timeBefore $ afterAll timeAfter spec'
spec = beforeAll timeBefore $ afterAll timeAfter $ aroundWith (\ioa _ -> ioa ()) spec''
spec' :: SpecWith Integer
spec' = mapSpecItem mapAction mapItem spec'' where
mapAction ioa _ = ioa ()
mapItem item@Item{..} = item{itemExample = itemExample' itemExample}
itemExample' ex params action callback
= ex params (mapExAction action) callback
mapExAction :: ((Integer -> IO ()) -> IO ()) -> (() -> IO ()) -> IO ()
mapExAction action unitAction
= action (mapExAction' unitAction)
mapExAction' :: (() -> IO ()) -> Integer -> IO ()
mapExAction' action _ = action ()
spec'' :: Spec
spec'' = do
describe "add" $ do
it "adds Nums" $ do
(add 1 1) `shouldBe` (2 :: Integer)
it "foo" $ do
(add 1 1) `shouldBe` (2 :: Integer)
describe "add2" $ do
it "adds Nums" $ do
(add 1 1) `shouldBe` (2 :: Integer)
it "bar" $ do
(add 1 1) `shouldBe` (2 :: Integer)
main = hspec specJust a demo that passing -Ox flags does work (GHC 8 only).
{-# OPTIONS_GHC -O2 -optc-O3 #-}
module Example where
factorial n = product [1..n]module ExampleSpec where
import Test.Hspec
import Example
spec :: Spec
spec = do
describe "factorial" $ do
it "should work" $ do
factorial 200 `shouldBe` product [1..200]
main = hspec specindex.js is a combination of preloaded, code and test cases with a bit of error handling. Other three files are required modules to run the tests.
const fs = require('fs')
//console.log(this)
const file1 = fs.readFileSync('/home/codewarrior/index.js')
console.log(file1.toString())
const file2 = fs.readFileSync('/runner/frameworks/javascript/cw-2.js')
console.log(file2.toString())
const file3 = fs.readFileSync('/runner/frameworks/javascript/chai-display.js')
console.log(file3.toString())
const file4 = fs.readFileSync('/runner/frameworks/javascript/display.js')
console.log(file4.toString())const assert = require('chai').assert
describe("Solution", function() {
it("should test for something", function() {
assert.strictEqual(1 + 1, 2);
});
});function add1(a, b) {
return a + b;
}
function add2(a, b) {
return a + b + 1;
}
function add3(a, b) {
throw new Error('boo');
}const {expect} = require('chai');
const fc = require('fast-check');
function addRefImpl(a, b) { return a + b; }
describe('independent generators', () => {
const gen1 =
fc.integer(-100, 100);
const prop = add => fc.property(gen1, gen1, (a, b) => add(a, b) === addRefImpl(a, b));
const params = {
verbose: true,
};
for (const add of [add1, add2, add3]) {
it(add.name, () => {
fc.assert(prop(add), params);
});
}
});
describe('combined generator, arguments as array', () => {
const gen =
fc.tuple(fc.integer(-100, 100), fc.integer(-100, 100));
const prop = add => fc.property(gen, ([a, b]) => add(a, b) === addRefImpl(a, b));
const params = {
verbose: true,
};
for (const add of [add1, add2, add3]) {
it(add.name, () => {
fc.assert(prop(add), params);
});
}
});
describe('combined generator, arguments and result as array', () => {
const gen =
fc.tuple(fc.integer(-100, 100), fc.integer(-100, 100)).map(([a, b]) =>
[a, b, addRefImpl(a, b)]);
const prop = add => fc.property(gen, ([a, b, expectedResult]) => add(a, b) === expectedResult);
const params = {
examples: [
[[1, 2, 3]],
],
verbose: true,
};
for (const add of [add1, add2, add3]) {
it(add.name, () => {
fc.assert(prop(add), params);
});
}
});
describe('combined generator, arguments and result as object', () => {
const gen =
fc.tuple(fc.integer(-100, 100), fc.integer(-100, 100)).map(([a, b]) =>
({a, b, expectedResult: addRefImpl(a, b)}));
const prop = add => fc.property(gen, ({a, b, expectedResult}) => add(a, b) === expectedResult);
const params = {
examples: [
[{a: 1, b: 2, expectedResult: 3}],
],
verbose: true,
};
for (const add of [add1, add2, add3]) {
it(add.name, () => {
fc.assert(prop(add), params);
});
}
});We are working for a Delivery company.This Kata requires the user to calculate the closest daily routes for Delivery based on the nearest location first to be delivered in the daily routes of deliveries to be made.
There is a single method - public List<List> ClosestXDestinations(int numDestinations,
List<List> allLocations, int numDeliveries), which takes in 3 parameters.
1. numDestinations - the number of destinations for the driver to deliver products to for today.
2. allLocations - A list of list having all locations of x and y coordinates of locations.
3. numDeliveries - the number of deliveries to be made today.
The closest destination is calculated as below.
Example:
--------
input:
numDestinations = 3
allLocations = [[1,2],[3,4],[1,-1]]
numDeliveries = 1
Output:
[[1,-1]]
Explanation:
The distance of the truck from location [1,2] is squareroot(5) = 2.236
The distance of the truck from location [3,4] is squareroot(25) = 5
The distance of the truck from location [1,-1] is squareroot(2) = 1.141
numDeliveries is 1, hence the output is [1,-1]
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import java.util.TreeMap;
public class NearestDelivery {
Integer val = 0;
int x = 0, y = 0;
public List<List<Integer>> ClosestXDestinations(int numDestinations,
List<List<Integer>> allLocations, int numDeliveries) {
TreeMap<Double, List<Integer>> sortedMap = new TreeMap<>();
for (int i = 0; i < allLocations.size(); i++) {
List<Integer> list = allLocations.get(i);
if (!list.isEmpty()) {
if (list.size() == 1) {
x = ((Integer) list.get(0)).intValue();
y = 0;
} else if (list.size() == 2) {
x = ((Integer) list.get(0)).intValue();
y = ((Integer) list.get(1)).intValue();
}
val = x * x + y * y;
double dVal = Math.sqrt(val);
sortedMap.put(dVal, list);
}
}
ArrayList<List<Integer>> as = new ArrayList<>(sortedMap.values());
while (as.size() > numDeliveries) {
as.remove(as.size() - 1);
}
return as;
}
}import org.junit.Test;
import static org.junit.Assert.assertEquals;
import org.junit.runners.JUnit4;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
// TODO: Replace examples and use TDD development by writing your own tests
public class SolutionTest {
@Test
public void testSomething() {
NearestDelivery sol = new NearestDelivery();
List<List<Integer>> allLocations = new ArrayList<>();
allLocations.add(Arrays.asList());
allLocations.add(Arrays.asList(2, 4));
allLocations.add(Arrays.asList(5, 3));
allLocations.add(Arrays.asList(2, 7));
allLocations.add(Arrays.asList(1, 8));
allLocations.add(Arrays.asList(7, 9));
assertEquals("[[2, 4], [5, 3]]", sol.ClosestXDestinations(6, allLocations, 2).toString());
}
}The given code barely passes at the limit of 23, even with -O2 enabled on Preloaded. GHC actually does lots of GC during compilation, so I guess we can apply this article to reduce GC times. Unfortunately, +RTS option is not available in OPTIONS_GHC so I need kazk's help here.
{-# LANGUAGE GADTs #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeOperators #-}
{-# OPTIONS_GHC -Wall -O2 #-}
module Kata.AdditionCommutes
( plusCommutes ) where
import Kata.AdditionCommutes.Definitions
( Z, S
, Natural(..), Equal(..)
, (:+:))
-- | x == x
refl :: Natural n -> Equal n n
refl NumZ = EqlZ
refl (NumS n) = EqlS (refl n)
-- | a == b -> b == a
sym :: Equal a b -> Equal b a
sym EqlZ = EqlZ
sym (EqlS p) = EqlS (sym p)
-- | a == b && b == c -> a == c
(<&>) :: Equal a b -> Equal b c -> Equal a c
(<&>) EqlZ EqlZ = EqlZ
(<&>) (EqlS a) (EqlS b) = EqlS (a <&> b)
-- | s(a) + b == a + s(b)
shove :: Natural a -> Natural b -> Equal (S a :+: b) (a :+: S b)
shove NumZ m = EqlS (refl m)
shove (NumS n) m = EqlS (shove n m)
-- | a + b == b + a
plusCommutes :: Natural a -> Natural b -> Equal (a :+: b) (b :+: a)
plusCommutes NumZ NumZ = EqlZ
plusCommutes a (NumS b) = sym (shove a b) <&> EqlS (plusCommutes a b)
plusCommutes (NumS a) b = EqlS (plusCommutes a b) <&> shove b a{-# LANGUAGE GADTs #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE TemplateHaskell #-}
module Kata.AdditionCommutesSpec (spec) where
import Kata.AdditionCommutes
import Kata.AdditionCommutes.Definitions
import Test.Hspec
import Test.Hspec.Codewars
-- | Verify that the functions' signature is correct:
solution :: Natural a -> Natural b -> Equal (a :+: b) (b :+: a)
solution = plusCommutes
main :: IO ()
main = hspec spec
spec :: Spec
spec = do
describe "Proof checking" $ do
it "Doesn't use any unsafe modules" $
solutionShouldHide $ Module "Unsafe.Coerce"
it "Simple tests" $ do
solution $(nat 0) $(nat 0) `shouldBe` $(proof 0)
solution $(nat 1) $(nat 0) `shouldBe` $(proof 1)
solution $(nat 5) $(nat 2) `shouldBe` $(proof 7)
solution $(nat 2) $(nat 7) `shouldBe` $(proof 9)
it "Methodical tests" $ $(makeTests [| solution |])