From 3a3e787b32ea1630cd5d4e0311b445e9701aea16 Mon Sep 17 00:00:00 2001
From: Olga Klisho <olga.klisho@jetbrains.com>
Date: Wed, 25 Feb 2026 12:40:06 +0000
Subject: [PATCH] [kotlin] KTIJ-37692 fix open range in
 ReplaceManualRangeWithIndicesCallsInspection

(cherry picked from commit 976cf795ab226678e66d45b1164309cf99971cde)

IJ-CR-193475

GitOrigin-RevId: 1549148f078ee0374c7af4c07a8d73c154618480
---
 .../tests/K2LocalInspectionTestGenerated.java          | 10 ++++++++++
 .../ReplaceManualRangeWithIndicesCallsInspection.kt    |  6 +++++-
 .../openRangeLastIndex.kt                              |  6 ++++++
 .../untilLastIndex.kt                                  |  5 +++++
 4 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/openRangeLastIndex.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/untilLastIndex.kt

diff --git a/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2LocalInspectionTestGenerated.java b/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2LocalInspectionTestGenerated.java
index c494040d4ebd..92c01f5dd994 100644
--- a/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2LocalInspectionTestGenerated.java
+++ b/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2LocalInspectionTestGenerated.java
@@ -9851,6 +9851,11 @@ public abstract class K2LocalInspectionTestGenerated extends AbstractK2LocalInsp
             runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/notUsedAsIndex.kt");
         }
 
+        @TestMetadata("openRangeLastIndex.kt")
+        public void testOpenRangeLastIndex() throws Exception {
+            runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/openRangeLastIndex.kt");
+        }
+
         @TestMetadata("qualifiedReceiverDifferentCollection.kt")
         public void testQualifiedReceiverDifferentCollection() throws Exception {
             runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/qualifiedReceiverDifferentCollection.kt");
@@ -9921,6 +9926,11 @@ public abstract class K2LocalInspectionTestGenerated extends AbstractK2LocalInsp
             runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/typeMismatch.kt");
         }
 
+        @TestMetadata("untilLastIndex.kt")
+        public void testUntilLastIndex() throws Exception {
+            runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/untilLastIndex.kt");
+        }
+
         @TestMetadata("usedForOtherArray.kt")
         public void testUsedForOtherArray() throws Exception {
             runTest("../../../idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/usedForOtherArray.kt");
diff --git a/plugins/kotlin/code-insight/inspections-shared/src/org/jetbrains/kotlin/idea/codeInsight/inspections/shared/ReplaceManualRangeWithIndicesCallsInspection.kt b/plugins/kotlin/code-insight/inspections-shared/src/org/jetbrains/kotlin/idea/codeInsight/inspections/shared/ReplaceManualRangeWithIndicesCallsInspection.kt
index 85f7c8f53e5b..1168dc66f514 100644
--- a/plugins/kotlin/code-insight/inspections-shared/src/org/jetbrains/kotlin/idea/codeInsight/inspections/shared/ReplaceManualRangeWithIndicesCallsInspection.kt
+++ b/plugins/kotlin/code-insight/inspections-shared/src/org/jetbrains/kotlin/idea/codeInsight/inspections/shared/ReplaceManualRangeWithIndicesCallsInspection.kt
@@ -201,7 +201,11 @@ class ReplaceManualRangeWithIndicesCallsInspection : KotlinApplicableInspectionB
         val target = extractTargetExpression(type, expression) ?: return null
         val selector = (target as? KtDotQualifiedExpression)?.selectorExpression ?: target
         val receiverType = resolveReceiverType(target) ?: return null
-        
+
+        // lastIndex is only valid for inclusive ranges (RANGE_TO)
+        // For open ranges (UNTIL, RANGE_UNTIL), 0..<lastIndex excludes the last element
+        if (selector.text == "lastIndex" && type != RANGE_TO) return null
+
         return when (selector.text) {
             "size", "lastIndex" -> if (receiverType.isArrayOrPrimitiveArray || receiverType.isSubtypeOf(StandardClassIds.Collection)) target else null
             "length" -> if (receiverType.isSubtypeOf(StandardClassIds.CharSequence)) target else null
diff --git a/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/openRangeLastIndex.kt b/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/openRangeLastIndex.kt
new file mode 100644
index 000000000000..e5da3e0d4a03
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/openRangeLastIndex.kt
@@ -0,0 +1,6 @@
+// WITH_STDLIB
+// LANGUAGE_VERSION: 1.9
+// PROBLEM: none
+fun test(list: List<String>) {
+    val x = 42 in 0<caret>..<list.lastIndex
+}
diff --git a/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/untilLastIndex.kt b/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/untilLastIndex.kt
new file mode 100644
index 000000000000..fe956e9b139f
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/inspectionsLocal/replaceManualRangeWithIndicesCalls/untilLastIndex.kt
@@ -0,0 +1,5 @@
+// WITH_STDLIB
+// PROBLEM: none
+fun test(list: List<String>) {
+    val x = 42 in 0 <caret>until list.lastIndex
+}