Split or glue together checks for not null and is instance + more intelligent use of filter vs filterTo

#KT-14284 Fixed
 #KT-14286 Fixed
 #KT-14287 Fixed
 #KT-14303 Fixed

idea/testData/intentions/loopToCallChain/filter/doNotSplitOutFilterIsInstance.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterIndexedTo(){}'"
+// IS_APPLICABLE_2: false
+fun foo(list: List<Any>, out: MutableList<Any>){
+    <caret>for ((i, any) in list.withIndex()) {
+        if (any is String && i % 2 == 0)
+            out.add(any)
+    }
+}

idea/testData/intentions/loopToCallChain/filter/doNotSplitOutFilterIsInstance.kt.after

@@ -0,0 +1,6 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterIndexedTo(){}'"
+// IS_APPLICABLE_2: false
+fun foo(list: List<Any>, out: MutableList<Any>){
+    list.filterIndexedTo(out) { i, any -> any is String && i % 2 == 0 }
+}

idea/testData/intentions/loopToCallChain/filter/doNotSplitOutFilterNotNull.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    <caret>for (l in list) {
+        if (l != null && l.startsWith("IMG:"))
+            println(l)
+    }
+}

idea/testData/intentions/loopToCallChain/filter/doNotSplitOutFilterNotNull.kt.after

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .filter { it != null && it.startsWith("IMG:") }
+            .forEach { println(it) }
+}

idea/testData/intentions/loopToCallChain/filter/doNotSplitOutFilterNotNull.kt.after2

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .asSequence()
+            .filter { it != null && it.startsWith("IMG:") }
+            .forEach { println(it) }
+}

idea/testData/intentions/loopToCallChain/filter/filterIndexedAndFlatMapWithContinue.kt

@@ -1,6 +1,6 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with '...flatMap{}.filterNot{}.mapTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filterNot{}.mapTo(){}'"
+// INTENTION_TEXT: "Replace with '...flatMap{}.filter{}.mapTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filter{}.mapTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<String>) {
     var i = 0
     <caret>for (s in list) {

idea/testData/intentions/loopToCallChain/filter/filterIndexedAndFlatMapWithContinue.kt.after

@@ -1,10 +1,10 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with '...flatMap{}.filterNot{}.mapTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filterNot{}.mapTo(){}'"
+// INTENTION_TEXT: "Replace with '...flatMap{}.filter{}.mapTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filter{}.mapTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<String>) {
     <caret>list
             .filterIndexed { i, s -> i % 10 != 0 }
             .flatMap { it.indices }
-            .filterNot { it == 10 }
+            .filter { it != 10 }
             .mapTo(target) { it.toString() }
 }

idea/testData/intentions/loopToCallChain/filter/filterIndexedAndFlatMapWithContinue.kt.after2

@@ -1,11 +1,11 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with '...flatMap{}.filterNot{}.mapTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filterNot{}.mapTo(){}'"
+// INTENTION_TEXT: "Replace with '...flatMap{}.filter{}.mapTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...flatMap{}.filter{}.mapTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<String>) {
     <caret>list
             .asSequence()
             .filterIndexed { i, s -> i % 10 != 0 }
             .flatMap { it.indices.asSequence() }
-            .filterNot { it == 10 }
+            .filter { it != 10 }
             .mapTo(target) { it.toString() }
 }

idea/testData/intentions/loopToCallChain/filter/filterNotTo.kt

@@ -3,7 +3,9 @@
 // IS_APPLICABLE_2: false
 fun foo(list: List<String>, target: MutableList<String>) {
     <caret>for (s in list) {
-        if (s.length == 0) continue
+        if (bar(s)) continue
         target.add(s)
     }
-}
+}
+
+fun bar(string: String): Boolean = TODO()

idea/testData/intentions/loopToCallChain/filter/filterNotTo.kt.after

@@ -2,5 +2,7 @@
 // INTENTION_TEXT: "Replace with 'filterNotTo(){}'"
 // IS_APPLICABLE_2: false
 fun foo(list: List<String>, target: MutableList<String>) {
-    <caret>list.filterNotTo(target) { it.length == 0 }
-}
+    list.filterNotTo(target) { bar(it) }
+}
+
+fun bar(string: String): Boolean = TODO()

idea/testData/intentions/loopToCallChain/filter/glueTogetherFilterNotNull.kt

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    <caret>for (l in list) {
+        if (l == null) continue
+        if (l.startsWith("IMG:"))
+            println(l)
+    }
+}

idea/testData/intentions/loopToCallChain/filter/glueTogetherFilterNotNull.kt.after

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .filter { it != null && it.startsWith("IMG:") }
+            .forEach { println(it) }
+}

idea/testData/intentions/loopToCallChain/filter/glueTogetherFilterNotNull.kt.after2

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .asSequence()
+            .filter { it != null && it.startsWith("IMG:") }
+            .forEach { println(it) }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterIsInstance.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterIsInstance<>().filterTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterIsInstance<>().filterTo(){}'"
+fun foo(list: List<Any>, out: MutableList<String>){
+    <caret>for (any in list) {
+        if (any is String && any.length > 0)
+            out.add(any)
+    }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterIsInstance.kt.after

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterIsInstance<>().filterTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterIsInstance<>().filterTo(){}'"
+fun foo(list: List<Any>, out: MutableList<String>){
+    list
+            .filterIsInstance<String>()
+            .filterTo(out) { it.length > 0 }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterIsInstance.kt.after2

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterIsInstance<>().filterTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterIsInstance<>().filterTo(){}'"
+fun foo(list: List<Any>, out: MutableList<String>){
+    list
+            .asSequence()
+            .filterIsInstance<String>()
+            .filterTo(out) { it.length > 0 }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    <caret>for (l in list) {
+        if (l != null && l.startsWith("IMG:"))
+            println(l.hashCode())
+    }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull.kt.after

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .filterNotNull()
+            .filter { it.startsWith("IMG:") }
+            .forEach { println(it.hashCode()) }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull.kt.after2

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .asSequence()
+            .filterNotNull()
+            .filter { it.startsWith("IMG:") }
+            .forEach { println(it.hashCode()) }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull2.kt

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    <caret>for (l in list) {
+        if (l == null || !l.startsWith("IMG:")) continue
+        println(l.hashCode())
+    }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull2.kt.after

@@ -0,0 +1,9 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .filterNotNull()
+            .filter { it.startsWith("IMG:") }
+            .forEach { println(it.hashCode()) }
+}

idea/testData/intentions/loopToCallChain/filter/splitOutFilterNotNull2.kt.after2

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'filterNotNull().filter{}.forEach{}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().filter{}.forEach{}'"
+fun foo(list: List<String?>){
+    list
+            .asSequence()
+            .filterNotNull()
+            .filter { it.startsWith("IMG:") }
+            .forEach { println(it.hashCode()) }
+}

idea/testData/intentions/loopToCallChain/firstOrNull/KT14292.kt

@@ -1,6 +1,6 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'filterNotNull().firstOrNull{}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().firstOrNull{}'"
+// INTENTION_TEXT: "Replace with 'firstOrNull{}'"
+// IS_APPLICABLE_2: false
 
 fun getFirstValue() = "value"
 

idea/testData/intentions/loopToCallChain/firstOrNull/KT14292.kt.after

@@ -1,13 +1,11 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'filterNotNull().firstOrNull{}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().firstOrNull{}'"
+// INTENTION_TEXT: "Replace with 'firstOrNull{}'"
+// IS_APPLICABLE_2: false
 
 fun getFirstValue() = "value"
 
 fun foo(list: List<String?>): String? {
     val value = getFirstValue()
-    val <caret>found: String? = list
-            .filterNotNull()
-            .firstOrNull { !it.startsWith("IMG:") && it.contains(value) }
+    val found: String? = list.firstOrNull { it != null && !it.startsWith("IMG:") && it.contains(value) }
     return found
 }

idea/testData/intentions/loopToCallChain/firstOrNull/KT14292.kt.after2

@@ -1,14 +0,0 @@
-// WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'filterNotNull().firstOrNull{}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().filterNotNull().firstOrNull{}'"
-
-fun getFirstValue() = "value"
-
-fun foo(list: List<String?>): String? {
-    val value = getFirstValue()
-    val <caret>found: String? = list
-            .asSequence()
-            .filterNotNull()
-            .firstOrNull { !it.startsWith("IMG:") && it.contains(value) }
-    return found
-}

idea/testData/intentions/loopToCallChain/indexOf/KT14303.kt

@@ -0,0 +1,11 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'indexOfFirst{}'"
+// IS_APPLICABLE_2: false
+fun f8_indexOfFirst_complex(value: String, list: List<Any?>):Int{
+    <caret>for ((i, any) in list.withIndex())
+        if (any != null)
+            if (any is String)
+                if (any == value)
+                    return i
+    return -1
+}

idea/testData/intentions/loopToCallChain/indexOf/KT14303.kt.after

@@ -0,0 +1,6 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with 'indexOfFirst{}'"
+// IS_APPLICABLE_2: false
+fun f8_indexOfFirst_complex(value: String, list: List<Any?>):Int{
+    return list.indexOfFirst { it != null && it is String && it == value }
+}

idea/testData/intentions/loopToCallChain/introduceIndex/indexWithNestedLoop.kt

@@ -1,6 +1,6 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'flatMap{}.filterNot{}.mapIndexedTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filterNot{}.mapIndexedTo(){}'"
+// INTENTION_TEXT: "Replace with 'flatMap{}.filter{}.mapIndexedTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filter{}.mapIndexedTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<Int>) {
     var i = 0
     <caret>for (s in list) {

idea/testData/intentions/loopToCallChain/introduceIndex/indexWithNestedLoop.kt.after

@@ -1,9 +1,9 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'flatMap{}.filterNot{}.mapIndexedTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filterNot{}.mapIndexedTo(){}'"
+// INTENTION_TEXT: "Replace with 'flatMap{}.filter{}.mapIndexedTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filter{}.mapIndexedTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<Int>) {
     <caret>list
             .flatMap { it.indices }
-            .filterNot { it == 10 }
+            .filter { it != 10 }
             .mapIndexedTo(target) { i, j -> i + j }
 }

idea/testData/intentions/loopToCallChain/introduceIndex/indexWithNestedLoop.kt.after2

@@ -1,10 +1,10 @@
 // WITH_RUNTIME
-// INTENTION_TEXT: "Replace with 'flatMap{}.filterNot{}.mapIndexedTo(){}'"
-// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filterNot{}.mapIndexedTo(){}'"
+// INTENTION_TEXT: "Replace with 'flatMap{}.filter{}.mapIndexedTo(){}'"
+// INTENTION_TEXT_2: "Replace with 'asSequence().flatMap{}.filter{}.mapIndexedTo(){}'"
 fun foo(list: List<String>, target: MutableCollection<Int>) {
     <caret>list
             .asSequence()
             .flatMap { it.indices.asSequence() }
-            .filterNot { it == 10 }
+            .filter { it != 10 }
             .mapIndexedTo(target) { i, j -> i + j }
 }

idea/testData/intentions/loopToCallChain/smartCasts/smartCastRequired2.kt

@@ -1,6 +1,6 @@
 // WITH_RUNTIME
-// IS_APPLICABLE: false
-// IS_APPLICABLE_2: false
+// INTENTION_TEXT: "Replace with '...filter{}.map{}.firstOrNull()'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...filter{}.map{}.firstOrNull()'"
 fun foo(list: List<Any>, o: Any): Int? {
     <caret>for (s in list) {
         if (s is String && s.length > 0) {

idea/testData/intentions/loopToCallChain/smartCasts/smartCastRequired2.kt.after

@@ -0,0 +1,10 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with '...filter{}.map{}.firstOrNull()'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...filter{}.map{}.firstOrNull()'"
+fun foo(list: List<Any>, o: Any): Int? {
+    return list
+            .filterIsInstance<String>()
+            .filter { it.length > 0 }
+            .map { it.length * 2 }
+            .firstOrNull()
+}

idea/testData/intentions/loopToCallChain/smartCasts/smartCastRequired2.kt.after2

@@ -0,0 +1,11 @@
+// WITH_RUNTIME
+// INTENTION_TEXT: "Replace with '...filter{}.map{}.firstOrNull()'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...filter{}.map{}.firstOrNull()'"
+fun foo(list: List<Any>, o: Any): Int? {
+    return list
+            .asSequence()
+            .filterIsInstance<String>()
+            .filter { it.length > 0 }
+            .map { it.length * 2 }
+            .firstOrNull()
+}