JSpecify: handling the return of a diamond operator anonymous object …

…method caller (uber#858) In reference to the [exception](uber#791 (comment)) mentioned in the discussion for uber#791 . Adding the test case to reproduce the same issue: ```java class Test { static class B<T>{ String build(){return "x";} } static String testNegative() { //We were getting the aforementioned mentioned exception when we tried to do this return new B<>().build(); } } ``` All unit tests have passed for the changes that were made for this. --------- Co-authored-by: Manu Sridharan <[email protected]>
msridhar · Nov 13, 2023 · 4af912d · 4af912d
1 parent 0141aca
commit 4af912d
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diff --git a/nullaway/src/main/java/com/uber/nullaway/GenericsChecks.java b/nullaway/src/main/java/com/uber/nullaway/GenericsChecks.java
@@ -788,10 +788,13 @@ public static Nullness getGenericReturnNullnessAtInvocation(
       return Nullness.NONNULL;
     }
     Type methodReceiverType =
-        castToNonNull(
-            getTreeType(((MemberSelectTree) tree.getMethodSelect()).getExpression(), state));
-    return getGenericMethodReturnTypeNullness(
-        invokedMethodSymbol, methodReceiverType, state, config);
+        getTreeType(((MemberSelectTree) tree.getMethodSelect()).getExpression(), state);
+    if (methodReceiverType == null) {
+      return Nullness.NONNULL;
+    } else {
+      return getGenericMethodReturnTypeNullness(
+          invokedMethodSymbol, methodReceiverType, state, config);
+    }
   }
 
   /**

diff --git a/nullaway/src/test/java/com/uber/nullaway/NullAwayJSpecifyGenericsTests.java b/nullaway/src/test/java/com/uber/nullaway/NullAwayJSpecifyGenericsTests.java
@@ -1522,6 +1522,24 @@ public void testForStaticMethodCallAsAParam() {
         .doTest();
   }
 
+  @Test
+  public void testForDiamondOperatorReturnedAsAMethodCaller() {
+    makeHelper()
+        .addSourceLines(
+            "Test.java",
+            "package com.uber;",
+            "import org.jspecify.annotations.Nullable;",
+            "class Test {",
+            "  static class B<T>{",
+            "   String build(){return \"x\";}",
+            "  }",
+            "  static String testNegative() {",
+            "   return new B<>().build();",
+            "  }",
+            "}")
+        .doTest();
+  }
+
   private CompilationTestHelper makeHelper() {
     return makeTestHelperWithArgs(
         Arrays.asList(