ControlFlow: properly throw exceptions of methods with side-effects

Fixes IDEA-215334 Dataflow doesn't see the array write inside lambda in try section

GitOrigin-RevId: e6b89b6b3a25cb3b0ace290455be11fbe261a0d2

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/CFGBuilder.java

@@ -689,7 +689,7 @@ public class CFGBuilder {
     }
     // Unknown function
     flushFields();
-    myAnalyzer.addConditionalRuntimeThrow();
+    myAnalyzer.addConditionalErrorThrow();
     PsiType functionalInterfaceType = functionalExpression.getType();
     myAnalyzer.addMethodThrows(LambdaUtil.getFunctionalInterfaceMethod(functionalInterfaceType), null);
     PsiType returnType = LambdaUtil.getFunctionalInterfaceReturnType(functionalInterfaceType);

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/ControlFlowAnalyzer.java

@@ -129,6 +129,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
     return myCodeFragment;
   }
 
+  @NotNull
   private PsiClassType createClassType(GlobalSearchScope scope, String fqn) {
     PsiClass aClass = JavaPsiFacade.getInstance(myProject).findClass(fqn, scope);
     if (aClass != null) return JavaPsiFacade.getElementFactory(myProject).createType(aClass);
@@ -1028,7 +1029,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
     finishElement(statement);
   }
 
-  void addConditionalRuntimeThrow() {
+  void addConditionalErrorThrow() {
     if (!shouldHandleException()) {
       return;
     }
@@ -1036,10 +1037,6 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
     pushUnknown();
     final ConditionalGotoInstruction ifNoException = addInstruction(new ConditionalGotoInstruction(null, false, null));
 
-    pushUnknown();
-    final ConditionalGotoInstruction ifError = addInstruction(new ConditionalGotoInstruction(null, false, null));
-    throwException(myExceptionCache.get(JAVA_LANG_RUNTIME_EXCEPTION), null);
-    ifError.setOffset(myCurrentFlow.getInstructionCount());
     throwException(myExceptionCache.get(JAVA_LANG_ERROR), null);
 
     ifNoException.setOffset(myCurrentFlow.getInstructionCount());
@@ -1145,7 +1142,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
       pushTrap(new InsideFinally(resourceList));
       startElement(resourceList);
       addInstruction(new FlushFieldsInstruction());
-      addThrows(null, closerExceptions.toArray(PsiClassType.EMPTY_ARRAY));
+      addThrows(null, closerExceptions);
       controlTransfer(new ExitFinallyTransfer(twrFinallyDescriptor), FList.emptyList()); // DfaControlTransferValue is on stack
       finishElement(resourceList);
       popTrap(InsideFinally.class);
@@ -1489,7 +1486,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
       addInstruction(new UnwrapSpecialFieldInstruction(SpecialField.UNBOX));
     }
     else if (TypeConversionUtil.isPrimitiveAndNotNull(actualType) && TypeConversionUtil.isAssignableFromPrimitiveWrapper(expectedType)) {
-      addConditionalRuntimeThrow();
+      addConditionalErrorThrow();
       PsiType boxedType = ((PsiPrimitiveType)actualType).getBoxedType(context);
       addInstruction(new BoxingInstruction(boxedType));
     }
@@ -1648,13 +1645,17 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
   }
 
   void addMethodThrows(PsiMethod method, @Nullable PsiElement explicitCall) {
-    if (method != null && shouldHandleException()) {
-      addThrows(explicitCall, method.getThrowsList().getReferencedTypes());
+    if (shouldHandleException()) {
+      addThrows(explicitCall, method == null ? Collections.emptyList() : Arrays.asList(method.getThrowsList().getReferencedTypes()));
     }
   }
 
-  private void addThrows(@Nullable PsiElement explicitCall, PsiClassType[] refs) {
-    for (PsiClassType ref : refs) {
+  private void addThrows(@Nullable PsiElement explicitCall, Collection<? extends PsiType> exceptions) {
+    List<PsiType> allExceptions = new ArrayList<>(exceptions);
+    allExceptions.add(myExceptionCache.get(JAVA_LANG_ERROR).getThrowable().getPsiType());
+    allExceptions.add(myExceptionCache.get(JAVA_LANG_RUNTIME_EXCEPTION).getThrowable().getPsiType());
+    List<PsiType> refs = PsiDisjunctionType.flattenAndRemoveDuplicates(allExceptions);
+    for (PsiType ref : refs) {
       pushUnknown();
       ConditionalGotoInstruction cond = new ConditionalGotoInstruction(null, false, null);
       addInstruction(cond);
@@ -1743,7 +1744,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
   }
 
   void addBareCall(@Nullable PsiMethodCallExpression expression, @NotNull PsiReferenceExpression reference) {
-    addConditionalRuntimeThrow();
+    addConditionalErrorThrow();
     PsiMethod method = ObjectUtils.tryCast(reference.resolve(), PsiMethod.class);
     List<? extends MethodContract> contracts =
       method == null ? Collections.emptyList() :
@@ -1766,7 +1767,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
       addInstruction(new BinopInstruction(JavaTokenType.EQEQ, null, PsiType.BOOLEAN));
       ConditionalGotoInstruction ifNotFail = new ConditionalGotoInstruction(null, true, null);
       addInstruction(ifNotFail);
-      addInstruction(new ReturnInstruction(myFactory.controlTransfer(new ExceptionTransfer(null), myTrapStack), anchor));
+      addInstruction(new ReturnInstruction(myFactory.controlTransfer(myExceptionCache.get(JAVA_LANG_THROWABLE), myTrapStack), anchor));
 
       ifNotFail.setOffset(myCurrentFlow.getInstructionCount());
     }
@@ -1852,7 +1853,7 @@ public class ControlFlowAnalyzer extends JavaElementVisitor {
         handleEscapedVariables(anonymousClass);
       }
 
-      addConditionalRuntimeThrow();
+      addConditionalErrorThrow();
       DfaValue precalculatedNewValue = getPrecalculatedNewValue(expression);
       List<? extends MethodContract> contracts = constructor == null ? Collections.emptyList() : JavaMethodContractUtil.getMethodContracts(constructor);
       addInstruction(new MethodCallInstruction(expression, precalculatedNewValue, DfaUtil.addRangeContracts(constructor, contracts)));

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/controlTransfer.kt

@@ -43,7 +43,7 @@ interface TransferTarget {
   /** @return next instruction states assuming no traps */
   fun dispatch(state: DfaMemoryState, runner: DataFlowRunner) : List<DfaInstructionState> = emptyList()
 }
-data class ExceptionTransfer(val throwable: DfaPsiType?) : TransferTarget {
+data class ExceptionTransfer(val throwable: DfaPsiType) : TransferTarget {
   override fun toString(): String = "Exception($throwable)"
 }
 data class InstructionTransfer(val offset: ControlFlow.ControlFlowOffset, private val toFlush: List<DfaVariableValue>) : TransferTarget {

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

@@ -0,0 +1,17 @@
+class App {
+  static void f(Runnable r) {
+    r.run();
+  }
+
+  public static void main(String[] args) {
+    RuntimeException[] exception = {null};
+    try {
+      f(() -> {
+        exception[0] = new RuntimeException();
+        throw exception[0];
+      });
+    } catch (RuntimeException e) {
+      System.out.println(e == exception[0]); // was false-positive
+    }
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspection8Test.java

@@ -245,4 +245,5 @@ public class DataFlowInspection8Test extends DataFlowInspectionTestCase {
     doTest();
   }
 
+  public void testLambdaWritesArrayInTry() { doTest(); }
 }