Support AssertJ hasSize() (#1229)

izeye · web-flow · commit a6273b0a8dac · 2025-06-28T16:33:45.000Z
This PR changes to support AssertJ `hasSize()`. See gh-1224
diff --git a/nullaway/src/main/java/com/uber/nullaway/handlers/AssertionHandler.java b/nullaway/src/main/java/com/uber/nullaway/handlers/AssertionHandler.java
@@ -61,6 +61,7 @@ public NullnessHint onDataflowVisitMethodInvocation(
     // assertThat(A).isInstanceOf(Foo.class)
     // A will not be NULL after this statement.
     if (methodNameUtil.isMethodIsNotNull(callee, state)
+        || methodNameUtil.isMethodHasSize(callee, state)
         || methodNameUtil.isMethodIsInstanceOf(callee, state)) {
       AccessPath ap = getAccessPathForNotNullAssertThatExpr(node, state, apContext);
       if (ap != null) {
diff --git a/nullaway/src/main/java/com/uber/nullaway/handlers/MethodNameUtil.java b/nullaway/src/main/java/com/uber/nullaway/handlers/MethodNameUtil.java
@@ -44,6 +44,7 @@ class MethodNameUtil {
   // Strings corresponding to the names of the methods (and their owners) used to identify
   // assertions in this handler.
   private static final String IS_NOT_NULL_METHOD = "isNotNull";
+  private static final String IS_HAS_SIZE_METHOD = "hasSize";
   private static final String IS_OWNER_TRUTH_SUBJECT = "com.google.common.truth.Subject";
   private static final String IS_INSTANCE_OF_METHOD = "isInstanceOf";
   private static final String IS_INSTANCE_OF_ANY_METHOD = "isInstanceOfAny";
@@ -88,6 +89,7 @@ class MethodNameUtil {
   // here refers to com.sun.tools.javac.util.Name. Comparing methods using Names is faster than
   // comparing using strings.
   private Name isNotNull;
+  private Name hasSize;
 
   private Name isInstanceOf;
   private Name isInstanceOfAny;
@@ -133,6 +135,7 @@ class MethodNameUtil {
   @Initializer
   void initializeMethodNames(Name.Table table) {
     isNotNull = table.fromString(IS_NOT_NULL_METHOD);
+    hasSize = table.fromString(IS_HAS_SIZE_METHOD);
     isOwnerTruthSubject = table.fromString(IS_OWNER_TRUTH_SUBJECT);
 
     isInstanceOf = table.fromString(IS_INSTANCE_OF_METHOD);
@@ -180,6 +183,10 @@ boolean isMethodIsNotNull(Symbol.MethodSymbol methodSymbol, VisitorState state)
         || matchesAssertJAssertMethod(methodSymbol, isNotNull, state);
   }
 
+  boolean isMethodHasSize(Symbol.MethodSymbol methodSymbol, VisitorState state) {
+    return matchesAssertJAssertMethod(methodSymbol, hasSize, state);
+  }
+
   boolean isMethodIsInstanceOf(Symbol.MethodSymbol methodSymbol, VisitorState state) {
     return matchesMethod(methodSymbol, isInstanceOf, isOwnerTruthSubject)
         || matchesAssertJAssertMethod(methodSymbol, isInstanceOf, state)
diff --git a/nullaway/src/test/java/com/uber/nullaway/AssertionLibsTests.java b/nullaway/src/test/java/com/uber/nullaway/AssertionLibsTests.java
@@ -549,4 +549,27 @@ public void collectionAssertIsNotNull() {
             "}")
         .doTest();
   }
+
+  @Test
+  public void collectionAssertHasSize() {
+    makeTestHelperWithArgs(
+            Arrays.asList(
+                "-d",
+                temporaryFolder.getRoot().getAbsolutePath(),
+                "-XepOpt:NullAway:AnnotatedPackages=com.uber",
+                "-XepOpt:NullAway:HandleTestAssertionLibraries=true"))
+        .addSourceLines(
+            "Test.java",
+            "import org.jspecify.annotations.*;",
+            "import java.util.Collection;",
+            "import static org.assertj.core.api.Assertions.assertThat;",
+            "@NullMarked",
+            "class Test {",
+            "  void test(@Nullable Collection<String> c) {",
+            "    assertThat(c).hasSize(1);",
+            "    c.size();",
+            "  }",
+            "}")
+        .doTest();
+  }
 }
