OptionalToIfInspection: added inspection to desugar optional chain to sequence of if statements (IDEA-212269)

GitOrigin-RevId: c83b70e05544529b3dfffe24bc87997910edcb56

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/optionalToIf/afterFlatMap.java

@@ -0,0 +1,54 @@
+// "Fix all 'Optional can be replaced with sequence of if statements' problems in file" "true"
+
+class Test {
+
+  private void reusesVariable(String in) {
+      if (in == null) throw new NullPointerException();
+      String id = id(in);
+      if (id == null) throw new NoSuchElementException("No value present");
+      Object out = id;
+  }
+
+  private void checkIsRemoved(String in) {
+      if (in == null) throw new NullPointerException();
+      String out = in;
+  }
+
+  void simple(String in) {
+      String out = "bar";
+      if (in != null) out = in;
+  }
+
+  void simpleWithMap(String in) {
+      String out = "bar";
+      if (in != null) {
+          String id = id(in);
+          if (id != null) out = id;
+      }
+  }
+
+  void nested(String in) {
+      String out = "bar";
+      if (in != null) out = in;
+  }
+
+  void outer(String in, String p) {
+      String out = "bar";
+      if (in != null) {
+          String value = in + in + p;
+          out = value;
+      }
+  }
+
+  void nullableOuter(String in, String p) {
+      String out = "bar";
+      if (in != null) {
+          if (p == null) throw new NullPointerException();
+          out = p;
+      }
+  }
+
+  <T> T id(T t) {
+    return t;
+  }
+}