diff --git a/domain/src/test/java/tachiyomi/domain/manga/interactor/SetFetchIntervalTest.kt b/domain/src/test/java/tachiyomi/domain/manga/interactor/SetFetchIntervalTest.kt
index d497d0b05..8c329ca22 100644
--- a/domain/src/test/java/tachiyomi/domain/manga/interactor/SetFetchIntervalTest.kt
+++ b/domain/src/test/java/tachiyomi/domain/manga/interactor/SetFetchIntervalTest.kt
@@ -6,8 +6,10 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.parallel.Execution
 import org.junit.jupiter.api.parallel.ExecutionMode
 import tachiyomi.domain.chapter.model.Chapter
-import java.time.Duration
 import java.time.ZonedDateTime
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.hours
+import kotlin.time.toJavaDuration
 
 @Execution(ExecutionMode.CONCURRENT)
 class SetFetchIntervalTest {
@@ -22,49 +24,34 @@ class SetFetchIntervalTest {
 
     @Test
     fun `calculateInterval returns default of 7 days when less than 3 distinct days`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..1).forEach {
-            val duration = Duration.ofHours(10)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..2).map {
+            chapterWithTime(chapter, 10.hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 7
     }
 
     @Test
     fun `calculateInterval returns 7 when 5 chapters in 1 day`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(10)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, 10.hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 7
     }
 
     @Test
     fun `calculateInterval returns 7 when 7 chapters in 48 hours, 2 day`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..2).forEach {
-            val duration = Duration.ofHours(24L)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
-        }
-        (1..5).forEach {
-            val duration = Duration.ofHours(48L)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..2).map {
+            chapterWithTime(chapter, 24.hours)
+        } + (1..5).map {
+            chapterWithTime(chapter, 48.hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 7
     }
 
     @Test
     fun `calculateInterval returns default of 1 day when interval less than 1`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(15L * it)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (15 * it).hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 1
     }
@@ -72,61 +59,46 @@ class SetFetchIntervalTest {
     // Normal interval calculation
     @Test
     fun `calculateInterval returns 1 when 5 chapters in 120 hours, 5 days`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(24L * it)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (24 * it).hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 1
     }
 
     @Test
     fun `calculateInterval returns 2 when 5 chapters in 240 hours, 10 days`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(48L * it)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (48 * it).hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 2
     }
 
     @Test
     fun `calculateInterval returns floored value when interval is decimal`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(25L * it)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (25 * it).hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 1
     }
 
     @Test
     fun `calculateInterval returns 1 when 5 chapters in 215 hours, 5 days`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(43L * it)
-            val newChapter = chapterAddTime(chapter, duration)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (43 * it).hours)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 1
     }
 
     @Test
     fun `calculateInterval returns interval based on fetch time if upload time not available`() {
-        val chapters = mutableListOf<Chapter>()
-        (1..5).forEach {
-            val duration = Duration.ofHours(25L * it)
-            val newChapter = chapterAddTime(chapter, duration).copy(dateUpload = 0L)
-            chapters.add(newChapter)
+        val chapters = (1..5).map {
+            chapterWithTime(chapter, (25 * it).hours).copy(dateUpload = 0L)
         }
         setFetchInterval.calculateInterval(chapters, testTime) shouldBe 1
     }
 
-    private fun chapterAddTime(chapter: Chapter, duration: Duration): Chapter {
-        val newTime = testTime.plus(duration).toEpochSecond() * 1000
+    private fun chapterWithTime(chapter: Chapter, duration: Duration): Chapter {
+        val newTime = testTime.plus(duration.toJavaDuration()).toEpochSecond() * 1000
         return chapter.copy(dateFetch = newTime, dateUpload = newTime)
     }
 }