Fixes IDEA-184723 "Data flow algorithm complexity" removing excessive temp variables

java/java-tests/testData/inspection/dataFlow/fixture/NullabilityBasics.java

@@ -0,0 +1,31 @@
+import org.jetbrains.annotations.*;
+
+class NullabilityBasics {
+
+  void test2() {
+    String x = getNullable();
+    if (x == null) {
+      System.out.println("x is null!");
+    }
+    if (isEmpty(x) && Math.random() > 0.5) {
+      return;
+    }
+    System.out.println(x.<warning descr="Method invocation 'trim' may produce 'java.lang.NullPointerException'">trim</warning>());
+  }
+
+  @Nullable String getNullable() {
+    return Math.random() > 0.5 ? null : "";
+  }
+
+  @Contract(value = "null -> true",pure = true)
+  static boolean isEmpty(@Nullable String s) {
+    return s == null || s.isEmpty();
+  }
+
+  void test(String x) {
+    if (x == null) {
+      System.out.println("x is null!");
+    }
+    System.out.println(x.<warning descr="Method invocation 'trim' may produce 'java.lang.NullPointerException'">trim</warning>());
+  }
+}

java/java-tests/testData/inspection/dataFlow/fixture/OptionalTooComplex.java

@@ -0,0 +1,48 @@
+import java.util.Optional;
+
+// IDEA-184723
+class OptionalTooComplex {
+  // Should not be too complex
+  public Long fetch() {
+    final PreparedStatement ps = builder
+      .setInteger(<warning descr="Argument 'opt().orElse(null)' might be null but passed to non annotated parameter">opt().orElse(null)</warning>)
+      .setInteger(<warning descr="Argument 'opt().orElse(null)' might be null but passed to non annotated parameter">opt().orElse(null)</warning>)
+      .setInteger(<warning descr="Argument 'opt().orElse(null)' might be null but passed to non annotated parameter">opt().orElse(null)</warning>)
+      .setInteger(<warning descr="Argument 'opt().orElse(null)' might be null but passed to non annotated parameter">opt().orElse(null)</warning>)
+      .setInteger(<warning descr="Argument 'opt().orElse(null)' might be null but passed to non annotated parameter">opt().orElse(null)</warning>)
+      .build();
+
+    ResultSet rs = null;
+    try {
+      rs = ps.executeQuery();
+      if (rs.next()) {
+        return rs.getLong();
+      }
+    } catch (final Exception e) {
+      throw new RuntimeException(e);
+    } finally {
+    }
+
+    return 0L;
+  }
+
+  interface ResultSet {
+    boolean next() throws Exception;
+
+    long getLong() throws Exception;
+  }
+
+  interface PreparedStatement {
+    ResultSet executeQuery() throws Exception;
+  }
+
+  native Optional<Integer> opt();
+
+  interface QueryBuilder {
+    QueryBuilder setInteger(Integer value);
+
+    PreparedStatement build();
+  }
+
+  QueryBuilder builder;
+}