@nullable declaration annotation makes varargs array elements @nullable…

… in JSpecify mode
uber · Sep 1, 2024 · 6b622c7 · 6b622c7
1 parent bc46f2e
commit 6b622c7
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Showing 3 changed files with 9 additions and 2 deletions.
diff --git a/nullaway/src/main/java/com/uber/nullaway/NullabilityUtil.java b/nullaway/src/main/java/com/uber/nullaway/NullabilityUtil.java
@@ -38,6 +38,7 @@
 import com.sun.source.tree.VariableTree;
 import com.sun.source.util.TreePath;
 import com.sun.tools.javac.code.Attribute;
+import com.sun.tools.javac.code.Flags;
 import com.sun.tools.javac.code.Symbol;
 import com.sun.tools.javac.code.TargetType;
 import com.sun.tools.javac.code.Type;
@@ -432,6 +433,11 @@ public static boolean isArrayElementNullable(Symbol arraySymbol, Config config)
         }
       }
     }
+    // In JSpecify mode, for varargs symbols we also consider the elements to be @Nullable if there
+    // is a @Nullable declaration annotation on the parameter
+    if (config.isJSpecifyMode() && (arraySymbol.flags() & Flags.VARARGS) != 0) {
+      return Nullness.hasNullableDeclarationAnnotation(arraySymbol, config);
+    }
     return false;
   }
 }
diff --git a/nullaway/src/main/java/com/uber/nullaway/Nullness.java b/nullaway/src/main/java/com/uber/nullaway/Nullness.java
@@ -282,7 +282,8 @@ private static boolean individualVarargsParamsAreNullable(Symbol paramSymbol, Co
         || NullabilityUtil.isArrayElementNullable(paramSymbol, config);
   }
 
-  private static boolean hasNullableDeclarationAnnotation(Symbol symbol, Config config) {
+  /** Checks if the symbol has a {@code @Nullable} declaration annotation */
+  public static boolean hasNullableDeclarationAnnotation(Symbol symbol, Config config) {
     return hasNullableAnnotation(symbol.getRawAttributes().stream(), config);
   }
 }
diff --git a/nullaway/src/test/java/com/uber/nullaway/jspecify/JSpecifyVarargsTests.java b/nullaway/src/test/java/com/uber/nullaway/jspecify/JSpecifyVarargsTests.java
@@ -57,7 +57,7 @@ public void testNullableVarargs() {
             " public static String takesNullableVarargs(Object o, @Nullable Object... others) {",
             "  String s = o.toString() + \" \" + others.toString();",
             "  for (Object other : others) {",
-            "    // no error here; requires a type-use annotation on the elements",
+            "    // BUG: Diagnostic contains: dereferenced expression other is @Nullable",
             "    s += other.toString();",
             "  }",
             "  return s;",