Checking that input variable is really used

idea/testData/intentions/loopToCallChain/filter_inputVarNotUsed.kt

@@ -0,0 +1,13 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+import java.util.*
+
+fun foo(list: List<String>): String? {
+    val random = Random()
+    for (s in list) {
+        if (random.nextBoolean()) {
+            return s
+        }
+    }
+    return null
+}

idea/testData/intentions/loopToCallChain/mapTo_inputVarNotUsed.kt

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+// IS_APPLICABLE: false
+fun foo(list: List<String>, target: MutableList<Int>) {
+    <caret>for (s in list) {
+        if (s.length > 0)
+            target.add(0)
+    }
+}