Support mapNotNull intermediate operation

idea/idea-jvm/src/com/intellij/debugger/streams/kotlin/lib/sequence/KotlinSequencesSupport.kt

@@ -1,6 +1,7 @@
 // Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.debugger.streams.kotlin.lib.sequence
 
+import com.intellij.debugger.streams.kotlin.resolve.MapNotNullResolver
 import com.intellij.debugger.streams.lib.IntermediateOperation
 import com.intellij.debugger.streams.lib.impl.*
 import com.intellij.debugger.streams.resolve.AppendResolver
@@ -30,6 +31,8 @@ class KotlinSequencesSupport : LibrarySupportBase() {
     addIntermediateOperationsSupport(ConcatOperation("plusElement", AppendResolver()))
 
     addIntermediateOperationsSupport(OrderBasedOperation("zipWithNext", PairMapResolver()))
+
+    addIntermediateOperationsSupport(OrderBasedOperation("mapNotNull", MapNotNullResolver()))
   }
 
   private fun filterOperations(vararg names: String): Array<IntermediateOperation> =

idea/idea-jvm/src/com/intellij/debugger/streams/kotlin/resolve/MapNotNullResolver.kt

@@ -0,0 +1,40 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.debugger.streams.kotlin.resolve
+
+import com.intellij.debugger.streams.resolve.ValuesOrderResolver
+import com.intellij.debugger.streams.trace.TraceElement
+import com.intellij.debugger.streams.trace.TraceInfo
+
+/**
+ * @author Vitaliy.Bibaev
+ */
+class MapNotNullResolver : ValuesOrderResolver {
+  override fun resolve(info: TraceInfo): ValuesOrderResolver.Result {
+    val before = info.valuesOrderBefore
+    val after = info.valuesOrderAfter
+
+    val invertedOrder = mutableMapOf<Int, Int>()
+    val beforeTimes = before.keys.sorted().toIntArray()
+    val afterTimes = after.keys.sorted().toIntArray()
+    var beforeIndex = 0
+    for (afterTime in afterTimes) {
+      while (beforeIndex < beforeTimes.size && afterTime > beforeTimes[beforeIndex]) beforeIndex += 1
+      val beforeTime = beforeTimes[beforeIndex - 1]
+      if (beforeTime < afterTime) {
+        invertedOrder[afterTime] = beforeTime
+      }
+    }
+
+    val direct = mutableMapOf<TraceElement, List<TraceElement>>()
+    val reverse = mutableMapOf<TraceElement, List<TraceElement>>()
+
+    for ((afterTime, beforeTime) in invertedOrder) {
+      val beforeElement = before.getValue(beforeTime)
+      val afterElement = after.getValue(afterTime)
+      direct[beforeElement] = listOf(afterElement)
+      reverse[afterElement] = listOf(beforeElement)
+    }
+
+    return ValuesOrderResolver.Result.of(direct, reverse)
+  }
+}

idea/testData/debugger/sequence/exec/sequence/outs/mapNotNull.out

@@ -13,21 +13,19 @@ toList
     after: nothing
 mappings for mapNotNull
   direct:
-    1 -> nothing
+    1 -> 2
     3 -> nothing
     4 -> nothing
-    5 -> nothing
+    5 -> 6
   reverse:
-    nothing <- 2
-    nothing <- 6
+    1 <- 2
+    5 <- 6
 mappings for toList
   direct:
     2 -> nothing
     6 -> nothing
   reverse:
     empty
-
-WRONG! Support will be implemented later
 Disconnected from the target VM
 
 Process finished with exit code 0