lambda: don't reject value compatibility for lambdas with control flow problems inside (IDEA-142107)

java/java-psi-impl/src/com/intellij/psi/impl/source/tree/java/PsiLambdaExpressionImpl.java

@@ -117,9 +117,8 @@ public class PsiLambdaExpressionImpl extends ExpressionPsiElement implements Psi
           return false;
         }
       }
-      catch (AnalysisCanceledException e) {
-        return false;
-      }
+      //error would be shown inside body
+      catch (AnalysisCanceledException ignore) {}
 
       for (PsiReturnStatement statement : PsiUtil.findReturnStatements((PsiCodeBlock)body)) {
         if (statement.getReturnValue() == null) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newLambda/ControlFlowAnalysisFailedValueCompatibilityUnchanged.java

@@ -0,0 +1,15 @@
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+class Test {
+  public static void processDifference(final Stream<String> stream, final Stream<String> cells) {
+    stream.map(rule -> {
+      try {
+        return cells.collect(Collectors.toMap(c -> c, null));
+      } finally {
+        System.out.println(<error descr="')' expected"><error descr="Expression expected">;</error></error><error descr="Unexpected token">)</error>;
+      }
+    });
+  }
+
+}

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

@@ -199,6 +199,10 @@ public class NewLambdaHighlightingTest extends LightDaemonAnalyzerTestCase {
     doTest();
   }
 
+  public void testControlFlowAnalysisFailedValueCompatibilityUnchanged() throws Exception {
+    doTest();
+  }
+
   private void doTest() {
     doTest(false);
   }