IDEA-206497 Replace with stream: support intermediate map operations in counting loops

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/joining/afterJoiningCountingExtracted.java

@@ -0,0 +1,13 @@
+// "Replace with collect" "true"
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class Test {
+  String foo(String[] lines) {
+    final String result = Arrays.stream(lines).collect(Collectors.joining("\n"));
+      // extracted into a separate var
+      return result;
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/streamApiMigration/joining/beforeJoiningCountingExtracted.java

@@ -0,0 +1,17 @@
+// "Replace with collect" "true"
+
+import java.util.List;
+
+public class Test {
+  String foo(String[] lines) {
+    final StringBuilder result = new StringBuilder();
+    fo<caret>r (int i = 0; i < lines.length; i++) {
+      final String line = lines[i];// extracted into a separate var
+      if (i > 0) {
+        result.append('\n');
+      }
+      result.append(line);
+    }
+    return result.toString();
+  }
+}