exclude anonymous classes/lambdas

palantir · Nov 7, 2019 · dec2f11 · dec2f11
1 parent 2136499
commit dec2f11
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Showing 2 changed files with 29 additions and 2 deletions.
diff --git a/...ror-prone/src/main/java/com/palantir/baseline/errorprone/InvocationHandlerDelegation.java b/...ror-prone/src/main/java/com/palantir/baseline/errorprone/InvocationHandlerDelegation.java
@@ -26,8 +26,10 @@
 import com.google.errorprone.matchers.Matchers;
 import com.google.errorprone.matchers.method.MethodMatchers;
 import com.sun.source.tree.ExpressionTree;
+import com.sun.source.tree.LambdaExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import com.sun.source.tree.MethodTree;
+import com.sun.source.tree.NewClassTree;
 import com.sun.source.tree.Tree;
 import com.sun.source.tree.TryTree;
 import java.lang.reflect.InvocationHandler;
@@ -77,10 +79,15 @@ public final class InvocationHandlerDelegation extends BugChecker implements Bug
             ExpressionTree.class, UNWRAP_ITE);
 
     private static final Matcher<MethodTree> HANDLES_ITE =
-            Matchers.contains(TryTree.class, (Matcher<TryTree>) (tree, state) ->
+            Matchers.anyOf(
+                    Matchers.contains(TryTree.class, (Matcher<TryTree>) (tree, state) ->
                     CONTAINS_METHOD_INVOKE.matches(tree.getBlock(), state)
                             && tree.getCatches().stream()
-                            .anyMatch(catchTree -> CONTAINS_UNWRAP_ITE.matches(catchTree.getBlock(), state)));
+                            .anyMatch(catchTree -> CONTAINS_UNWRAP_ITE.matches(catchTree.getBlock(), state))),
+                    // If Method.invoke occurs in a lambda or anonymous class, we don't have enough
+                    // conviction that it's a bug.
+                    Matchers.contains(LambdaExpressionTree.class, CONTAINS_METHOD_INVOKE::matches),
+                    Matchers.contains(NewClassTree.class, CONTAINS_METHOD_INVOKE::matches));
 
     private static final Matcher<MethodInvocationTree> MATCHER = Matchers.allOf(
             METHOD_INVOKE_ENCLOSED_BY_INVOCATION_HANDLER,

diff --git a/...prone/src/test/java/com/palantir/baseline/errorprone/InvocationHandlerDelegationTest.java b/...prone/src/test/java/com/palantir/baseline/errorprone/InvocationHandlerDelegationTest.java
@@ -132,6 +132,26 @@ void testCorrectInvocationHandler_doesntRethrow() {
                 "}")
                 .doTest();
     }
+
+    @Test
+    void testCorrectInvocationHandler_lambda() {
+        helper().addSourceLines(
+                "Test.java",
+                "import java.lang.reflect.*;",
+                "import com.google.common.util.concurrent.*;",
+                "abstract class Test implements InvocationHandler {",
+                "  @Override",
+                "  public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {",
+                // Avoid flagging invocations nested in anonymous classes or lambdas
+                "  return FluentFuture.from(executor().submit(() -> method.invoke(this, args)))",
+                "    .catching(InvocationTargetException.class, ignored -> null, MoreExecutors.directExecutor())",
+                "    .get();",
+                "  }",
+                "  abstract ListeningExecutorService executor();",
+                "}")
+                .doTest();
+    }
+
     private CompilationTestHelper helper() {
         return CompilationTestHelper.newInstance(InvocationHandlerDelegation.class, getClass());
     }