Java: Handle chained assignment of fields in class initializer (IDEA-188872)

java/java-analysis-impl/src/com/intellij/codeInspection/defUse/DefUseInspectionBase.java

@@ -140,6 +140,20 @@ public class DefUseInspectionBase extends AbstractBaseJavaLocalInspectionTool {
         final List<PsiAssignmentExpression> assignments = collectAssignments(field, classInitializer);
         if (!assignments.isEmpty()) {
           boolean isDefinitely = HighlightControlFlowUtil.variableDefinitelyAssignedIn(field, classInitializer.getBody());
+          if (isDefinitely) {
+            try {
+              ControlFlow flow = HighlightControlFlowUtil.getControlFlowNoConstantEvaluate(classInitializer.getBody());
+              if (ControlFlowUtil.getReadBeforeWrite(flow)
+                                 .stream()
+                                 .anyMatch(read -> (isStatic || ExpressionUtil.isEffectivelyUnqualified(read)) &&
+                                                   read.isReferenceTo(field))) {
+                isDefinitely = false;
+              }
+            }
+            catch (AnalysisCanceledException e) {
+              // ignore
+            }
+          }
           fieldWrites.add(FieldWrite.createAssignments(isDefinitely, assignments));
         }
       }

java/java-tests/testData/inspection/defUse/ChainedFieldInitializer.java

@@ -0,0 +1,21 @@
+import java.util.*;
+
+class Base {
+  protected Base(Map<String, Class<?>> aMap) {
+  }
+}
+
+class SubClass extends Base {
+  private static Map<String, Class<?>> aMap = new TreeMap<>();
+  static {
+    aMap = Collections.unmodifiableMap(aMap);
+  }
+  public SubClass() { super(aMap); }
+}
+
+class WithStatic {
+  private static int n = 1;
+  static {
+    n = n + 1;
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DefUseTest.java

@@ -59,6 +59,7 @@ public class DefUseTest extends LightCodeInsightFixtureTestCase {
   public void testNestedTryFinallyInEndlessLoop() { doTest(); }
   public void testNestedTryFinallyInForLoop() { doTest(); }
   public void testFieldInitializer() { doTest(); }
+  public void testChainedFieldInitializer() { doTest(); }
   public void testFieldIgnoringRedundantInitializer() {
     DefUseInspection inspection = new DefUseInspection();
     inspection.REPORT_REDUNDANT_INITIALIZER = false;