diff --git a/fpdfsdk/fpdf_editpage_embeddertest.cpp b/fpdfsdk/fpdf_editpage_embeddertest.cpp
index 54e2f59..b578550 100644
--- a/fpdfsdk/fpdf_editpage_embeddertest.cpp
+++ b/fpdfsdk/fpdf_editpage_embeddertest.cpp
@@ -576,6 +576,10 @@
     CloseSavedPage(saved_page);
     CloseSavedDocument();
   }
+
+  // Negative testing.
+  EXPECT_FALSE(FPDFPageObj_SetIsActive(nullptr, false));
+  EXPECT_FALSE(FPDFPageObj_SetIsActive(nullptr, true));
 }
 
 TEST_F(FPDFEditPageEmbedderTest, Bug378120423) {