Add Setter law test for optic conversion

arrow-kt · Feb 2, 2018 · 74bc110 · 74bc110
1 parent 9745952
commit 74bc110
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Showing 2 changed files with 53 additions and 1 deletion.
diff --git a/arrow-optics/src/test/kotlin/arrow/optics/SetterTest.kt b/arrow-optics/src/test/kotlin/arrow/optics/SetterTest.kt
@@ -1,6 +1,7 @@
 package arrow.optics
 
 import arrow.core.getOrElse
+import arrow.data.k
 import io.kotlintest.KTestJUnitRunner
 import io.kotlintest.properties.Gen
 import io.kotlintest.properties.forAll
@@ -11,12 +12,14 @@ import arrow.test.generators.genFunctionAToB
 import arrow.test.generators.genOption
 import arrow.syntax.either.left
 import arrow.syntax.either.right
+import arrow.syntax.foldable.combineAll
 import org.junit.runner.RunWith
 
 @RunWith(KTestJUnitRunner::class)
 class SetterTest : UnitSpec() {
 
     init {
+
         testLaws(SetterLaws.laws(
                 setter = Setter.id(),
                 aGen = Gen.int(),
@@ -41,6 +44,54 @@ class SetterTest : UnitSpec() {
                 EQA = Eq.any()
         ))
 
+        "asFold should behave as valid Fold: size" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().size(sum) == sumPrism.getOption(sum).map { 1 }.getOrElse { 0 }
+            }
+        }
+
+        "asFold should behave as valid Fold: nonEmpty" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().nonEmpty(sum) == sumPrism.getOption(sum).nonEmpty()
+            }
+        }
+
+        "asFold should behave as valid Fold: isEmpty" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().isEmpty(sum) == sumPrism.getOption(sum).isEmpty()
+            }
+        }
+
+        "asFold should behave as valid Fold: getAll" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().getAll(sum) == sumPrism.getOption(sum).toList().k()
+            }
+        }
+
+        "asFold should behave as valid Fold: combineAll" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().combineAll(sum) == sumPrism.getOption(sum).combineAll()
+            }
+        }
+
+        "asFold should behave as valid Fold: fold" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().fold(sum) == sumPrism.getOption(sum).combineAll()
+            }
+        }
+
+        "asFold should behave as valid Fold: headOption" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().headOption(sum) == sumPrism.getOption(sum)
+            }
+        }
+
+        "asFold should behave as valid Fold: lastOption" {
+            forAll(SumGen) { sum: SumType ->
+                sumPrism.asFold().lastOption(sum) == sumPrism.getOption(sum)
+            }
+        }
+
         "Joining two lenses together with same target should yield same result" {
             val userTokenStringSetter = userSetter compose tokenSetter
             val joinedSetter = tokenSetter.choice(userTokenStringSetter)

diff --git a/arrow-test/src/main/kotlin/arrow/test/laws/SetterLaws.kt b/arrow-test/src/main/kotlin/arrow/test/laws/SetterLaws.kt
@@ -6,10 +6,11 @@ import arrow.core.identity
 import io.kotlintest.properties.Gen
 import io.kotlintest.properties.forAll
 import arrow.optics.Setter
+import arrow.typeclasses.eq
 
 object SetterLaws {
 
-    inline fun <reified A, reified B> laws(setter: Setter<A, B>, aGen: Gen<A>, bGen: Gen<B>, funcGen: Gen<(B) -> B>, EQA: Eq<A>) = listOf(
+    inline fun <reified A, reified B> laws(setter: Setter<A, B>, aGen: Gen<A>, bGen: Gen<B>, funcGen: Gen<(B) -> B>, EQA: Eq<A> = eq()) = listOf(
             Law("Setter law: set is idempotent", { setIdempotent(setter, aGen, bGen, EQA) }),
             Law("Setter law: modify identity", { modifyIdentity(setter, aGen, EQA) }),
             Law("Setter law: compose modify", { composeModify(setter, aGen, EQA, funcGen) }),