Traverse PDF page tree only once in CPDF_Document Try 3

core/fpdfapi/parser/cpdf_document_unittest.cpp

 // Copyright 2016 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/fpdfapi/parser/cpdf_document.h"
 
 #include <memory>
 
 #include "core/fpdfapi/cpdf_modulemgr.h"
 #include "core/fpdfapi/parser/cpdf_array.h"
@@ skipping 77 matching lines @@
   }
   void TearDown() override {}
 };
 
 TEST_F(cpdf_document_test, GetPages) {
   std::unique_ptr<CPDF_TestDocumentForPages> document =
       pdfium::MakeUnique<CPDF_TestDocumentForPages>();
   for (int i = 0; i < 7; i++) {
     CPDF_Dictionary* page = document->GetPage(i);
     ASSERT_TRUE(page);
-    ASSERT_TRUE(page->GetObjectFor("PageNumbering"));
+    ASSERT_TRUE(page->KeyExist("PageNumbering"));
     EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
   }
   CPDF_Dictionary* page = document->GetPage(7);
   EXPECT_FALSE(page);
 }
 
 TEST_F(cpdf_document_test, GetPagesReverseOrder) {
   std::unique_ptr<CPDF_TestDocumentForPages> document =
       pdfium::MakeUnique<CPDF_TestDocumentForPages>();
   for (int i = 6; i >= 0; i--) {
     CPDF_Dictionary* page = document->GetPage(i);
     ASSERT_TRUE(page);
-    ASSERT_TRUE(page->GetObjectFor("PageNumbering"));
+    ASSERT_TRUE(page->KeyExist("PageNumbering"));
     EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
   }
   CPDF_Dictionary* page = document->GetPage(7);
   EXPECT_FALSE(page);
 }
 
+TEST(cpdf_document, GetPagesInDisorder) {
+  std::unique_ptr<CPDF_TestDocumentForPages> document =
+      pdfium::MakeUnique<CPDF_TestDocumentForPages>();
+
+  CPDF_Dictionary* page = document->GetPage(1);
+  ASSERT_TRUE(page);
+  ASSERT_TRUE(page->KeyExist("PageNumbering"));
+  EXPECT_EQ(1, page->GetIntegerFor("PageNumbering"));
+
+  page = document->GetPage(3);
+  ASSERT_TRUE(page);
+  ASSERT_TRUE(page->KeyExist("PageNumbering"));
+  EXPECT_EQ(3, page->GetIntegerFor("PageNumbering"));
+
+  page = document->GetPage(7);
+  EXPECT_FALSE(page);
+
+  page = document->GetPage(6);
+  ASSERT_TRUE(page);
+  ASSERT_TRUE(page->KeyExist("PageNumbering"));
+  EXPECT_EQ(6, page->GetIntegerFor("PageNumbering"));
+}
+
 TEST_F(cpdf_document_test, UseCachedPageObjNumIfHaveNotPagesDict) {
   // ObjNum can be added in CPDF_DataAvail::IsPageAvail, and PagesDict
   // can be not exists in this case.
   // (case, when hint table is used to page check in CPDF_DataAvail).
   CPDF_Document document(pdfium::MakeUnique<CPDF_Parser>());
   std::unique_ptr<CPDF_Dictionary> dict(new CPDF_Dictionary());
   const int page_count = 100;
   dict->SetIntegerFor("N", page_count);
   document.LoadLinearizedDoc(dict.get());
   ASSERT_EQ(page_count, document.GetPageCount());
   CPDF_Object* page_stub = new CPDF_Dictionary();
   const uint32_t obj_num = document.AddIndirectObject(page_stub);
   const int test_page_num = 33;
 
   EXPECT_FALSE(document.IsPageLoaded(test_page_num));
   EXPECT_EQ(nullptr, document.GetPage(test_page_num));
 
   document.SetPageObjNum(test_page_num, obj_num);
 
   EXPECT_TRUE(document.IsPageLoaded(test_page_num));
   EXPECT_EQ(page_stub, document.GetPage(test_page_num));
 }