Merge "Fix for a crash in IntervalList" into snap-temp-L22600000955094635

4 files changed, 69 insertions, 1 deletions

diff --git a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/grid/LazyGridTest.kt b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/grid/LazyGridTest.kt
index 7b5e760aad2..396ec8dbb82 100644
--- a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/grid/LazyGridTest.kt
+++ b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/grid/LazyGridTest.kt
@@ -721,6 +721,26 @@ class LazyGridTest(
     }
 
     @Test
+    fun maxIntElements_withKey_startInMiddle() {
+        val itemSize = with(rule.density) { 15.toDp() }
+
+        rule.setContent {
+            LazyGrid(
+                cells = 1,
+                modifier = Modifier.size(itemSize),
+                state = LazyGridState(firstVisibleItemIndex = Int.MAX_VALUE / 2)
+            ) {
+                items(Int.MAX_VALUE, key = { it }) {
+                    Box(Modifier.size(itemSize).testTag("$it"))
+                }
+            }
+        }
+
+        rule.onNodeWithTag("${Int.MAX_VALUE / 2}")
+            .assertMainAxisStartPositionInRootIsEqualTo(0.dp)
+    }
+
+    @Test
     fun pointerInputScrollingIsAllowedWhenUserScrollingIsEnabled() {
         val itemSize = with(rule.density) { 30.toDp() }
         rule.setContentWithTestViewConfiguration {
diff --git a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/list/LazyListTest.kt b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/list/LazyListTest.kt
index e38956c49e4..48a7d4bc94e 100644
--- a/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/list/LazyListTest.kt
+++ b/compose/foundation/foundation/src/androidAndroidTest/kotlin/androidx/compose/foundation/lazy/list/LazyListTest.kt
@@ -1508,6 +1508,28 @@ class LazyListTest(orientation: Orientation) : BaseLazyListTestWithOrientation(o
     }
 
     @Test
+    fun maxIntElements_withKey_startInMiddle() {
+        val itemSize = with(rule.density) { 15.toDp() }
+
+        rule.setContent {
+            LazyColumnOrRow(
+                modifier = Modifier.requiredSize(itemSize),
+                state = LazyListState(firstVisibleItemIndex = Int.MAX_VALUE / 2)
+            ) {
+                items(Int.MAX_VALUE, key = { it }) {
+                    Box(
+                        Modifier
+                            .size(itemSize)
+                            .testTag("$it"))
+                }
+            }
+        }
+
+        rule.onNodeWithTag("${Int.MAX_VALUE / 2}")
+            .assertStartPositionInRootIsEqualTo(0.dp)
+    }
+
+    @Test
     fun scrollingByExactlyTheItemSize_switchesTheFirstVisibleItem() {
         val itemSize = with(rule.density) { 30.toDp() }
         lateinit var state: LazyListState
diff --git a/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/IntervalList.kt b/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/IntervalList.kt
index 19c8d19e586..f855bea50b5 100644
--- a/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/IntervalList.kt
+++ b/compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/lazy/layout/IntervalList.kt
@@ -147,7 +147,7 @@ class MutableIntervalList<T> : IntervalList<T> {
         }
 
         var intervalIndex = intervals.binarySearch(fromIndex)
-        var itemIndex = fromIndex
+        var itemIndex = intervals[intervalIndex].startIndex
         while (itemIndex <= toIndex) {
             val interval = intervals[intervalIndex]
             block(interval)
diff --git a/compose/foundation/foundation/src/test/kotlin/androidx/compose/foundation/lazy/MutableIntervalListTest.kt b/compose/foundation/foundation/src/test/kotlin/androidx/compose/foundation/lazy/MutableIntervalListTest.kt
index 9ec910c8a65..78b57260a32 100644
--- a/compose/foundation/foundation/src/test/kotlin/androidx/compose/foundation/lazy/MutableIntervalListTest.kt
+++ b/compose/foundation/foundation/src/test/kotlin/androidx/compose/foundation/lazy/MutableIntervalListTest.kt
@@ -211,6 +211,20 @@ class MutableIntervalListTest {
     }
 
     @Test
+    fun forEach_fromIndexIsInTheMiddleOfInterval() {
+        intervalList.addInterval(10, 0) // startIndex = 0
+        intervalList.addInterval(1, 1) // startIndex = 10
+        intervalList.addInterval(1, 2) // startIndex = 11
+        val intervals = mutableListOf<IntervalList.Interval<Int>>()
+
+        intervalList.forEach(fromIndex = 5, toIndex = 10) {
+            intervals.add(it)
+        }
+
+        assertThat(intervals.map { it.startIndex }).isEqualTo(listOf(0, 10))
+    }
+
+    @Test
     fun forEach_startLargerThanEndThrows() {
         addFiveSingleIntervals()
 
@@ -261,6 +275,18 @@ class MutableIntervalListTest {
         assertThat(wasException4).isTrue()
     }
 
+    @Test
+    fun forEach_MAX_VALUE_size_andFromIndexIsInTheMiddle() {
+        intervalList.addInterval(Int.MAX_VALUE, 0)
+        val intervals = mutableListOf<IntervalList.Interval<Int>>()
+
+        intervalList.forEach(fromIndex = Int.MAX_VALUE / 2, toIndex = Int.MAX_VALUE - 1) {
+            intervals.add(it)
+        }
+
+        assertThat(intervals.map { it.startIndex }).isEqualTo(listOf(0))
+    }
+
     private fun addFiveSingleIntervals() {
         intervalList.addInterval(1, 10)
         intervalList.addInterval(1, 20)