Java inspection: Check if the returned variable is read in the 'finally' block of an enclosing 'try' statement in "Move return to computation" inspection (IDEA-121153)

java/java-impl/src/com/intellij/codeInspection/intermediaryVariable/ReturnSeparatedFromComputationInspection.java

@@ -186,22 +186,20 @@ public class ReturnSeparatedFromComputationInspection extends BaseJavaBatchLocal
   }
 
   private static boolean isApplicable(@NotNull ControlFlow flow, @NotNull ReturnContext context) {
-    final int flowStart = flow.getStartOffset(context.returnScope);
-    final int flowEnd = flow.getEndOffset(context.returnScope);
-    if (flowStart < 0 || flowEnd < 0) return false;
-
-    final int returnStartOffset = flow.getStartOffset(context.returnStatement);
-    final int returnEndOffset = flow.getEndOffset(context.returnStatement);
-    if (returnStartOffset < 0 || returnEndOffset < 0) return false;
-
     if (hasChainedAssignmentsInScope(flow, context.returnedVariable, context.returnStatement)) {
       return false;
     }
-
-    if (context.returnScope != context.variableScope &&
-        ControlFlowUtil.hasObservableThrowExitPoints(flow, flowStart, flowEnd,
-                                                     new PsiElement[]{context.refactoredStatement}, context.variableScope)) {
-      return false;
+    if (context.returnScope != context.variableScope) {
+      if (ControlFlowUtil.isVariableReadInFinally(flow, context.returnScope, context.variableScope, context.returnedVariable)) {
+        return false;
+      }
+      final int flowStart = flow.getStartOffset(context.returnScope);
+      final int flowEnd = flow.getEndOffset(context.returnScope);
+      if (flowStart < 0 || flowEnd < 0) return false;
+      if (ControlFlowUtil.hasObservableThrowExitPoints(flow, flowStart, flowEnd,
+                                                       new PsiElement[]{context.refactoredStatement}, context.variableScope)) {
+        return false;
+      }
     }
 
     Mover mover = new Mover(flow, context.refactoredStatement, context.returnedVariable, context.returnType, true);

java/java-psi-impl/src/com/intellij/psi/controlFlow/ControlFlowUtil.java

@@ -258,6 +258,37 @@ public class ControlFlowUtil {
     return false;
   }
 
+  public static boolean isVariableReadInFinally(@NotNull ControlFlow flow,
+                                                @Nullable PsiElement startElement,
+                                                @NotNull PsiElement enclosingCodeFragment,
+                                                @NotNull PsiVariable variable) {
+    for (PsiElement element = startElement; element != null && element != enclosingCodeFragment; element = element.getParent()) {
+      if (element instanceof PsiCodeBlock) {
+        final PsiElement parent = element.getParent();
+        if (parent instanceof PsiTryStatement) {
+          final PsiTryStatement tryStatement = (PsiTryStatement)parent;
+          if (tryStatement.getTryBlock() == element) {
+            final PsiCodeBlock finallyBlock = tryStatement.getFinallyBlock();
+            if (finallyBlock != null) {
+              final List<Instruction> instructions = flow.getInstructions();
+              final int startOffset = flow.getStartOffset(finallyBlock);
+              final int endOffset = flow.getEndOffset(finallyBlock);
+              LOG.assertTrue(startOffset >= 0, "flow start");
+              LOG.assertTrue(endOffset <= instructions.size(), "flow end");
+              for (int i = startOffset; i < endOffset; i++) {
+                final Instruction instruction = instructions.get(i);
+                if (instruction instanceof ReadVariableInstruction && ((ReadVariableInstruction)instruction).variable == variable) {
+                  return true;
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+    return false;
+  }
+
   public static List<PsiVariable> getInputVariables(ControlFlow flow, int start, int end) {
     List<PsiVariable> usedVariables = getUsedVariables(flow, start, end);
     ArrayList<PsiVariable> array = new ArrayList<PsiVariable>(usedVariables.size());

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/returnSeparatedFromComputation/beforeReadInFinally.java

@@ -0,0 +1,14 @@
+// "Move 'return' closer to computation of the value of 'n'" "false"
+class T {
+  int f(boolean b) {
+    int n = -1;
+    try {
+      if (b) throw new RuntimeException();
+      n = 1;
+      re<caret>turn n;
+    }
+    finally {
+      System.out.println(n);
+    }
+  }
+}