feat(#31): add div operations for AnyInt

changelog.md

@@ -32,8 +32,8 @@ class NotEmptyList<out E> : NotEmptyCollection<E>
 class NotEmptySet<out E> : NotEmptyCollection<E>
 ```
 
-- Binary operations (`plus`, `minus`, `times`) for the `AnyInt` hierarchy (issue
-  [#31](https://github.com/kotools/types/issues/31)).
+- Binary operations (`plus`, `minus`, `times`, `div`) for the `AnyInt` hierarchy
+  (issue [#31](https://github.com/kotools/types/issues/31)).
 
 ```kotlin
 val x: AnyInt = NonZeroInt.random()

src/commonMain/kotlin/kotools/types/number/AnyInt.kt

@@ -59,6 +59,13 @@ public operator fun AnyInt.times(other: Int): Int = toInt() * other
 @SinceKotoolsTypes("4.1")
 public operator fun AnyInt.times(other: AnyInt): Int = toInt() * other
 
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun AnyInt.div(other: NonZeroInt): Int = toInt() / other
+
 internal sealed interface AnyIntSerializer<I : AnyInt> : KSerializer<I> {
     val serialName: Result<NotBlankString>
 

src/commonMain/kotlin/kotools/types/number/NegativeInt.kt

@@ -38,6 +38,28 @@ public sealed interface NegativeInt : AnyInt {
     override fun toString(): String
 }
 
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun NegativeInt.div(other: StrictlyPositiveInt): NegativeInt {
+    val result: Int = toInt() / other
+    return result.toNegativeInt()
+        .getOrThrow()
+}
+
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun NegativeInt.div(other: StrictlyNegativeInt): PositiveInt {
+    val result: Int = toInt() / other
+    return result.toPositiveInt()
+        .getOrThrow()
+}
+
 /**
  * Returns this number as an encapsulated [NegativeInt], which may involve
  * rounding or truncation, or returns an encapsulated [IllegalArgumentException]

src/commonMain/kotlin/kotools/types/number/NonZeroInt.kt

@@ -47,6 +47,13 @@ public sealed interface NonZeroInt : AnyInt {
     override fun toString(): String
 }
 
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun Int.div(other: NonZeroInt): Int = this / other.toInt()
+
 /**
  * Returns this number as an encapsulated [NonZeroInt], which may involve
  * rounding or truncation, or returns an encapsulated [IllegalArgumentException]

src/commonMain/kotlin/kotools/types/number/PositiveInt.kt

@@ -35,6 +35,28 @@ public sealed interface PositiveInt : AnyInt {
     override fun toString(): String
 }
 
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun PositiveInt.div(other: StrictlyPositiveInt): PositiveInt {
+    val result: Int = toInt() / other
+    return result.toPositiveInt()
+        .getOrThrow()
+}
+
+/**
+ * Divides this integer by the [other] one, truncating the result to an integer
+ * that is closer to [zero][ZeroInt].
+ */
+@SinceKotoolsTypes("4.1")
+public operator fun PositiveInt.div(other: StrictlyNegativeInt): NegativeInt {
+    val result: Int = toInt() / other
+    return result.toNegativeInt()
+        .getOrThrow()
+}
+
 /**
  * Returns this number as an encapsulated [PositiveInt], which may involve
  * rounding or truncation, or returns an encapsulated [IllegalArgumentException]

src/commonTest/kotlin/kotools/types/number/AnyIntTest.kt

@@ -81,6 +81,14 @@ class AnyIntTest {
         val result: Int = x * y
         result shouldEqual x.toInt() * y.toInt()
     }
+
+    @Test
+    fun div_should_pass_with_a_NonZeroInt() {
+        val x: AnyInt = PositiveInt.random()
+        val y: NonZeroInt = NonZeroInt.random()
+        val result: Int = x / y
+        result shouldEqual x.toInt() / y.toInt()
+    }
 }
 
 class AnyIntSerializerTest {

src/commonTest/kotlin/kotools/types/number/NegativeIntTest.kt

@@ -32,6 +32,22 @@ class NegativeIntCompanionTest {
 }
 
 class NegativeIntTest {
+    @Test
+    fun div_should_return_a_NegativeInt_with_a_StrictlyPositiveInt() {
+        val x: NegativeInt = NegativeInt.random()
+        val y: StrictlyPositiveInt = StrictlyPositiveInt.random()
+        val result: NegativeInt = x / y
+        result.toInt() shouldEqual x.toInt() / y.toInt()
+    }
+
+    @Test
+    fun div_should_return_a_PositiveInt_with_a_StrictlyNegativeInt() {
+        val x: NegativeInt = NegativeInt.random()
+        val y: StrictlyNegativeInt = StrictlyNegativeInt.random()
+        val result: PositiveInt = x / y
+        result.toInt() shouldEqual x.toInt() / y.toInt()
+    }
+
     @Test
     fun number_toNegativeInt_should_pass_with_a_negative_Int() {
         val value: Number = NegativeInt.random()

src/commonTest/kotlin/kotools/types/number/NonZeroIntTest.kt

@@ -9,6 +9,7 @@ import kotools.types.Package
 import kotools.types.shouldEqual
 import kotools.types.shouldHaveAMessage
 import kotools.types.shouldNotEqual
+import kotlin.random.Random
 import kotlin.test.Test
 import kotlin.test.assertFailsWith
 
@@ -33,6 +34,14 @@ class NonZeroIntCompanionTest {
 }
 
 class NonZeroIntTest {
+    @Test
+    fun int_div_should_pass_with_a_NonZeroInt() {
+        val x: Int = Random.nextInt()
+        val y: NonZeroInt = NonZeroInt.random()
+        val result: Int = x / y
+        result shouldEqual x / y.toInt()
+    }
+
     @Test
     fun number_toNonZeroInt_should_pass_with_an_Int_other_than_zero() {
         val value: Number = NonZeroInt.random()

src/commonTest/kotlin/kotools/types/number/PositiveIntTest.kt

@@ -33,6 +33,22 @@ class PositiveIntCompanionTest {
 }
 
 class PositiveIntTest {
+    @Test
+    fun div_should_return_a_PositiveInt_with_a_StrictlyPositiveInt() {
+        val x: PositiveInt = PositiveInt.random()
+        val y: StrictlyPositiveInt = StrictlyPositiveInt.random()
+        val result: PositiveInt = x / y
+        result.toInt() shouldEqual x.toInt() / y.toInt()
+    }
+
+    @Test
+    fun div_should_return_a_NegativeInt_with_a_StrictlyNegativeInt() {
+        val x: PositiveInt = PositiveInt.random()
+        val y: StrictlyNegativeInt = StrictlyNegativeInt.random()
+        val result: NegativeInt = x / y
+        result.toInt() shouldEqual x.toInt() / y.toInt()
+    }
+
     @Test
     fun number_toPositiveInt_should_pass_with_a_positive_Int() {
         val expected: Number = PositiveInt.random().toInt()