Tests: Add test cases for #10702 and #10717

Add test cases for parsing an empty file and a truncated file.

Tests/LibPDF/TestPDF.cpp

@@ -4,6 +4,8 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/Forward.h>
+#include <AK/String.h>
 #include <LibCore/MappedFile.h>
 #include <LibPDF/Document.h>
 #include <LibTest/Macros.h>
@@ -29,3 +31,17 @@ TEST_CASE(complex_pdf)
     auto document = PDF::Document::create(file->bytes());
     EXPECT_EQ(document->get_page_count(), 3U);
 }
+
+TEST_CASE(empty_file_issue_10702)
+{
+    AK::ReadonlyBytes empty;
+    auto document = PDF::Document::create(empty);
+    EXPECT(document.is_null());
+}
+
+TEST_CASE(truncated_pdf_header_issue_10717)
+{
+    AK::String string { "%PDF-2.11%" };
+    auto document = PDF::Document::create(string.bytes());
+    EXPECT(document.is_null());
+}