🆖 📘 👧 为Kotlin项目选择一个断言库 🌈 🐑 👩🏽‍🍳

在一个旧项目中，JUnit的断言，kotlin.test和AssertJ被堆积了。这不是他唯一的问题：它通常是费奥多尔叔叔写的一封信，没有时间停下来把它变成一个单一的形式。现在这个时候到了。

本文将包含一项小型研究，根据主观标准，哪些主张更好。最初，我想做一些简单的事情：进行一组测试，以便快速复制和粘贴铆钉选项。然后他重点介绍了常规测试数据，自动进行了一些检查，以及一切进行得如何...结果是一块小的Rosetta石头，对于选择适合您实际情况的断言库，本文可能对您有用。

我将立即保留一点，即本文不会比较测试框架，测试方法和一些棘手的数据验证方法。我们将讨论简单的断言。

如果您懒得阅读无聊的推理，我的磨难历史和其他细节，那么您可以直接进入比较结果。

有点背景

Scala, — ScalaTest. , - , - .

Kotlin, - , , Kotest ( , ).

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ScalaTest — .
JUnit 5 — Java-.
kotlin.test — multiplatform . — JUnit, .
AssertJ — . FestAssert, - .
Kotest — KotlinTest, kotlin.test. , ScalaTest. 1-22 — scala.
Truth — . , AssertJ.
Hamrest — . valid4j.
Strikt — AssertJ .
Kluent — , JUnit ( — kotlin.test), Kotest. — , .
Atrium — , AssertJ, . — ( maven/gradle).
Expekt — Chai.js. : — 4 .
AssertK — AssertJ, AssertK ( ).
HamKrest — Hamrest, HamKrest ( Hamcrest ).

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assertThrows<T>{...}

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assertThrows(expectedClass){...}

. , kotlin.test Asserter: , . , ?:)

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: 0 — , 0.5 — , 1 — . — 9 .

-, , . . , . , - , " " , " " . .


Kotest	±	±	+	+	+	+	+	-	6.0
Kluent	±	±	+	+	+	+	+	-	6.0
AssertJ	±	+	±	+	±	+	+	±	6.0
Truth	±	+	+	+	-	+	+	-	5.5
Strikt	±	±	±	+	+	+	+	-	5.5
ScalaTest	±	±	±	+	+	+	+	-	5.5
HamKrest	±	-	±	+	+	±	+	-	5.5
AssertK	±	±	±	+	±	+	+	-	5.0
Atrium	±	±	±	+	+	±	+	-	5.0
Hamrest	±	±	±	+	-	±	+	-	5.0
JUnit	+	+	-	±	+	-	±	-	4.5
kotlin.test	+	±	-	-	+	-	-	-	3.5
Expekt	±	±	-	+	-	±	+	-	3.5

Kotest

要仅连接断言，您需要更深入地研究。我认为，很难立即理解这一点。
, reified, : .
: . .
: <Click to see difference> .
: .
: , .

Kluent

"hello".shouldBeEqualTo("hello"), "hello" `should be equal to` "hello". DSL .

invoking { block() } shouldThrow expectedClass.kotlin withMessage expectedMessage

, , . Expected Iterable to contain none of "[1, 3]" — , Iterable .
: <Click to see difference> .
: .

AssertJ

— … , containsExactly, — hasSameElementsAs, — .usingRecursiveComparison().isEqualTo.
: <Click to see difference> .
: - , . , , .

: .usingRecursiveComparison(), . : , , . , , ,

assertThat(actual)
    .usingRecursiveComparison()
    .isNotEqualTo(unexpected)

: .

: . , DSL.

Truth

, .
: , , assertThrows JUnit5. , JUnit , ?
: , , : containsAtLeastElementsIn. , assertThat(actual).isEqualTo(expected).
: <Click to see difference> .
: .
: , .

" ":

expected: 1
but was : 2
at asserts.truth.TruthAsserts.simpleAssert(TruthAsserts.kt:10)
at common.FailedAssertsTestBase.simple assert should have descriptive message(FailedAssertsTestBase.kt:20)
at [[Reflective call: 4 frames collapsed (https://goo.gl/aH3UyP)]].(:0)
at [[Testing framework: 27 frames collapsed (https://goo.gl/aH3UyP)]].(:0)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at [[Testing framework: 9 frames collapsed (https://goo.gl/aH3UyP)]].(:0)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at [[Testing framework: 9 frames collapsed (https://goo.gl/aH3UyP)]].(:0)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
at [[Testing framework: 17 frames collapsed (https://goo.gl/aH3UyP)]].(:0)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99)
...

Strikt

, reified, : .
: expectThat(haystack).not().contains(needle), expectThat(collection).doesNotContain(items).
: contentEquals. : expectThat(actual).not().contentEquals(unexpected). , , Array<T> Strikt - . — containsExactly, — containsExactlyInAnyOrder.

: . , . :

val actual: Array<String> = arrayOf("1")
val expected: Array<String> = arrayOf("2")
expectThat(actual).contentEquals(expected)

, contentEquals. , contentEquals :

infix fun <T> Assertion.Builder<Array<out T>>.contentEquals(other: Array<out T>)

val actual: Array<out String> = arrayOf("1")
val expected: Array<String> = arrayOf("2")
expectThat(actual).contentEquals(expected)

: <Click to see difference>.
: , .
: .

ScalaTest

: .
: , . .
: DSL contains, contains include, theSameElementsAs.
: , .
: , .

HamKrest

, , . — , .
, Hamcrest, - : -.

— :

assertThat( {
    block()
}, throws(has(RuntimeException::message, equalTo(expectedMessage))))

: . - 3,5 . : assertThat(collection, allOf(items.map { hasElement(it) })).
.
: .
: <Click to see difference>.

— - :

expected: a value that not contains 1 or contains 3
but contains 1 or contains 3

AssertK

— AssertJ. ( , -).
: AssertJ assertThat(collection).containsAll(items), AssertK , containsAll vararg. , containsAll(1,2,3), . , , — . — . , containsOnly containsExactly.
: <Click to see difference>.
: - , , .
: .usingRecursiveComparison() .

— ( ), :

expected to contain exactly:<[3, 4, 5]> but was:<[1, 2, 3]>
at index:0 unexpected:<1>
at index:1 unexpected:<2>
at index:1 expected:<4>
at index:2 expected:<5>

Atrium

: fluent infix. assertThat(x).isEqualTo(y) x shouldBe y, , expect(x).toBe(y) expect(x) toBe y. , , "". - o: expect(x) contains o atLeast 1 butAtMost 2 value "hello". , , . infix- ( - ), Atrium fluent-.
: : notToBe, containsNot. . , : contains vararg, containsElementsOf , . , contains(1,2,3), . expect(collection).containsNot.elementsOf(items).
, toList.
, reified, : .
: .
: <Click to see difference>.

: ( , ), :

expected that subject: [4, 2, 1]        (java.util.Arrays.ArrayList <938196491>)
◆ does not contain:
⚬ an entry which is: 1        (kotlin.Int <211381230>)
  ✘  number of such entries: 1
       is: 0        (kotlin.Int <1934798916>)
    has at least one element: true
       is: true

Hamcrest

: (

assertThat(actual, `is`(not(unexpected)))

assertThat(actual, not(unexpected))

containsString vs contains vs hasItem vs hasItems. , : hasItems vararg, Set<T> T . , hasItems(1,2,3), .

assertThat(collection, allOf(items.map { hasItem(it) }))

assertThat(collection, not(anyOf(items.map { hasItem(it) })))

hasItems, ± "", , .
: .
: <Click to see difference>.
: .
: .

JUnit

: - assertEquals(expected, actual), : assertArrayEquals, assertIterableEquals ..
: , JUnit - , .
: assertLinesMatch(listOf(".*$needle.*"), listOf(haystack)) , .
: assertLinesMatch, , assertIterableEquals.
: , assertIterableEquals Map Set , .
: .

kotlin.test

. JUnit, . , .
, JUnit, :
.
assertIterableEquals, .
: JUnit' assertEquals, kotlin.test , .
: .

Expekt

expect(x).equal(y) x.should.equal(y), . , .
: contains(item) should.have.elements(items) should.contain.elements(items). containsAll. , : should.have.elements vararg. , should.have.elements(1,2,3), . any: .should.not.contain.any.elements.
: , .
.
.
: .
: .
: <Click to see difference>.

Kotest, Kluent AssertJ. , Kotlin , AssertJ ( ). , .

— , , AssertJ. , , .

为Kotlin项目选择一个断言库

有点背景

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