inference: ensure to convert disjunction type to lub (IDEA-150364)

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/constraints/ExpressionCompatibilityConstraint.java

@@ -50,7 +50,7 @@ public class ExpressionCompatibilityConstraint extends InputOutputConstraintForm
         return assignmentCompatible;
       }
     
-      final PsiType exprType = myExpression.getType();
+      PsiType exprType = myExpression.getType();
 
       if (exprType instanceof PsiLambdaParameterType) {
         return false;
@@ -67,6 +67,10 @@ public class ExpressionCompatibilityConstraint extends InputOutputConstraintForm
       }
 
       if (exprType != null && exprType != PsiType.NULL) {
+        if (exprType instanceof PsiDisjunctionType) {
+          exprType = ((PsiDisjunctionType)exprType).getLeastUpperBound();
+        }
+
         constraints.add(new TypeCompatibilityConstraint(myT, exprType));
       }
       return true;

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/DisjunctionTypes.java

@@ -0,0 +1,25 @@
+class Test {
+  public static void main(String[] args) throws Exception {
+    try {
+    }
+    catch (Exception | Error e) {
+      <error descr="Unhandled exception: java.lang.Throwable">throw identity(identity(e));</error>
+    }
+
+    try {
+    }
+    catch (Exception | Error e) {
+      <error descr="Unhandled exception: java.lang.Throwable">throw identity(e);</error>
+    }
+
+    try {
+    }
+    catch (Exception | Error e) {
+      throw e;
+    }
+  }
+
+  public static <T> T identity(T throwable) {
+    return throwable;
+  }
+}

java/java-tests/testSrc/com/intellij/codeInsight/daemon/lambda/GraphInferenceHighlightingTest.java

@@ -359,6 +359,10 @@ public class GraphInferenceHighlightingTest extends LightDaemonAnalyzerTestCase
     doTest();
   }
 
+  public void testDisjunctionTypes() throws Exception {
+    doTest();
+  }
+
   private void doTest() throws Exception {
     doTest(false);
   }