Minor code improvements for IntegralRange and IntegralRangeTest.

Author: ianbrandt

subprojects/user-defined-integrals-in-kotlin/src/main/kotlin/org/sdkotlin/integral/IntegralRange.kt

@@ -22,7 +22,7 @@ class IntegralRange<I : Integral<I>>(
 	}
 
 	override fun contains(value: I): Boolean =
-		start <= value && value <= endInclusive
+		value in start..endInclusive
 
 	override fun isEmpty(): Boolean = start > endInclusive
 

subprojects/user-defined-integrals-in-kotlin/src/test/kotlin/org/sdkotlin/integral/IntegralRangeTest.kt

@@ -10,7 +10,7 @@ class IntegralRangeTest {
 	fun `test equals, hashCode, and toString`() {
 
 		EqualsVerifier.forClass(IntegralRange::class.java)
-			.withIgnoredFields("endExclusive\$delegate", "$\$delegate_0")
+			.withIgnoredFields($$"endExclusive$delegate", $$$"$$delegate_0")
 			// Required per https://github.com/jqno/equalsverifier/issues/1082.
 			.withPrefabValues(
 				Integral::class.java,
@@ -30,7 +30,7 @@ class IntegralRangeTest {
 		val blue: ClosedRange<SignedIntegral> = one..two
 
 		EqualsVerifier.forExamples(red, blue)
-			.withIgnoredFields("endExclusive\$delegate", "$\$delegate_0")
+			.withIgnoredFields($$"endExclusive$delegate", $$$"$$delegate_0")
 			.verify()
 	}
 }