From 13a15de783fc78d8298c4f5448ad2781861abce8 Mon Sep 17 00:00:00 2001
From: Manu Sridharan <msridhar@gmail.com>
Date: Sun, 15 Dec 2024 08:51:26 -0800
Subject: [PATCH] WIP

---
 .../com/uber/nullaway/CodeAnnotationInfo.java | 19 ++++++++--
 .../jspecify/NullMarkednessTests.java         | 38 +++++++++++++++++++
 2 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/nullaway/src/main/java/com/uber/nullaway/CodeAnnotationInfo.java b/nullaway/src/main/java/com/uber/nullaway/CodeAnnotationInfo.java
index 4844efc308..58d4db3859 100644
--- a/nullaway/src/main/java/com/uber/nullaway/CodeAnnotationInfo.java
+++ b/nullaway/src/main/java/com/uber/nullaway/CodeAnnotationInfo.java
@@ -83,9 +83,7 @@ private static boolean fromAnnotatedPackage(
     String className = outermostClassSymbol.getQualifiedName().toString();
     Symbol.PackageSymbol enclosingPackage = ASTHelpers.enclosingPackage(outermostClassSymbol);
     if (!config.fromExplicitlyAnnotatedPackage(className)
-        && !(enclosingPackage != null
-            && hasDirectAnnotationWithSimpleName(
-                enclosingPackage, NullabilityUtil.NULLMARKED_SIMPLE_NAME))) {
+        && !(enclosingPackage != null && annotatedAsNullMarkedPackage(enclosingPackage))) {
       // By default, unknown code is unannotated unless @NullMarked or configured as annotated by
       // package name
       return false;
@@ -104,6 +102,21 @@ && hasDirectAnnotationWithSimpleName(
     return true;
   }
 
+  private static final String NONNULLAPI_NAME = "org.springframework.lang.NonNullApi";
+  private static final String NONNULLFIELDS_NAME = "org.springframework.lang.NonNullFields";
+
+  private static boolean annotatedAsNullMarkedPackage(Symbol.PackageSymbol enclosingPackage) {
+    return hasDirectAnnotationWithSimpleName(
+            enclosingPackage, NullabilityUtil.NULLMARKED_SIMPLE_NAME)
+        || (packageHasAnnotation(enclosingPackage, NONNULLAPI_NAME)
+            && packageHasAnnotation(enclosingPackage, NONNULLFIELDS_NAME));
+  }
+
+  private static boolean packageHasAnnotation(Symbol sym, String annotationClass) {
+    return sym.getAnnotationMirrors().stream()
+        .anyMatch(a -> a.type.tsym.getQualifiedName().contentEquals(annotationClass));
+  }
+
   /**
    * Check if a symbol comes from generated code.
    *
diff --git a/nullaway/src/test/java/com/uber/nullaway/jspecify/NullMarkednessTests.java b/nullaway/src/test/java/com/uber/nullaway/jspecify/NullMarkednessTests.java
index 705aa8180d..0e0ae388e9 100644
--- a/nullaway/src/test/java/com/uber/nullaway/jspecify/NullMarkednessTests.java
+++ b/nullaway/src/test/java/com/uber/nullaway/jspecify/NullMarkednessTests.java
@@ -43,6 +43,44 @@ public void nullMarkedPackageLevel() {
         .doTest();
   }
 
+  @Test
+  public void springNullMarkedPackage() {
+    defaultCompilationHelper
+        .addSourceLines(
+            "package-info.java",
+            "@NonNullApi @NonNullFields package com.example.thirdparty;",
+            "import org.springframework.lang.NonNullApi;",
+            "import org.springframework.lang.NonNullFields;")
+        .addSourceLines(
+            "ThirdPartyAnnotatedUtils.java",
+            "package com.example.thirdparty;",
+            "import org.jspecify.annotations.Nullable;",
+            "public class ThirdPartyAnnotatedUtils {",
+            "  public static String toStringOrDefault(@Nullable Object o1, String s) {",
+            "    if (o1 != null) {",
+            "      return o1.toString();",
+            "    }",
+            "    return s;",
+            "  }",
+            "}")
+        .addSourceLines(
+            "Test.java",
+            "package com.uber;",
+            "import com.example.thirdparty.ThirdPartyAnnotatedUtils;",
+            "public class Test {",
+            "  public static void test(Object o) {",
+            "    // Safe: passing @NonNull on both args",
+            "    ThirdPartyAnnotatedUtils.toStringOrDefault(o, \"default\");",
+            "    // Safe: first arg is @Nullable",
+            "    ThirdPartyAnnotatedUtils.toStringOrDefault(null, \"default\");",
+            "    // Unsafe: @NullMarked means the second arg is @NonNull by default, not @Nullable",
+            "    // BUG: Diagnostic contains: passing @Nullable parameter",
+            "    ThirdPartyAnnotatedUtils.toStringOrDefault(o, null);",
+            "  }",
+            "}")
+        .doTest();
+  }
+
   @Test
   public void nullMarkedPackageEnablesChecking() {
     defaultCompilationHelper