Test bad inputs to FPDFAvail_* APIs.

Add a couple more FPDFDataAvailEmbedderTests to improve test coverage.

Change-Id: I222a5fa25cd7fe1906ca58e394fe1df9d22364cc
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/58932
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

fpdfsdk/fpdf_dataavail_embeddertest.cpp

diff --git a/fpdfsdk/fpdf_dataavail_embeddertest.cpp b/fpdfsdk/fpdf_dataavail_embeddertest.cpp
index 137c5c9..64560b6 100644
--- a/fpdfsdk/fpdf_dataavail_embeddertest.cpp
+++ b/fpdfsdk/fpdf_dataavail_embeddertest.cpp
@@ -378,3 +378,20 @@
   // Test that api is robust enough to handle the bad case.
   EXPECT_FALSE(FPDF_GetMetaText(document_, "Type", nullptr, 0));
 }
+
+TEST_F(FPDFDataAvailEmbedderTest, BadInputsToAPIs) {
+  EXPECT_EQ(PDF_DATA_ERROR, FPDFAvail_IsDocAvail(nullptr, nullptr));
+  EXPECT_FALSE(FPDFAvail_GetDocument(nullptr, nullptr));
+  EXPECT_EQ(0, FPDFAvail_GetFirstPageNum(nullptr));
+  EXPECT_EQ(PDF_DATA_ERROR, FPDFAvail_IsPageAvail(nullptr, 0, nullptr));
+  EXPECT_EQ(PDF_FORM_ERROR, FPDFAvail_IsFormAvail(nullptr, nullptr));
+  EXPECT_EQ(PDF_LINEARIZATION_UNKNOWN, FPDFAvail_IsLinearized(nullptr));
+}
+
+TEST_F(FPDFDataAvailEmbedderTest, NegativePageIndex) {
+  TestAsyncLoader loader("linearized.pdf");
+  avail_ = FPDFAvail_Create(loader.file_avail(), loader.file_access());
+  ASSERT_EQ(PDF_DATA_AVAIL, FPDFAvail_IsDocAvail(avail_, loader.hints()));
+  EXPECT_EQ(PDF_DATA_NOTAVAIL,
+            FPDFAvail_IsPageAvail(avail_, -1, loader.hints()));
+}