Add CPDF_Document::GetPage() unittests

core/fpdfapi/parser/cpdf_document_unittest.cpp

Index: core/fpdfapi/parser/cpdf_document_unittest.cpp
diff --git a/core/fpdfapi/parser/cpdf_document_unittest.cpp b/core/fpdfapi/parser/cpdf_document_unittest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..56ff28fbf53213a27630bd22cf3602d053993509
--- /dev/null
+++ b/core/fpdfapi/parser/cpdf_document_unittest.cpp
@@ -0,0 +1,108 @@
+// 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"
+#include "core/fpdfapi/parser/cpdf_dictionary.h"
+#include "core/fpdfapi/parser/cpdf_parser.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+CPDF_Dictionary* CreatePageTreeNode(CPDF_Array* kids,
+                                    CPDF_Document* pDoc,
+                                    int count) {
+  CPDF_Dictionary* pageNode = new CPDF_Dictionary();
+  pageNode->SetStringFor("Type", "Pages");
+  pageNode->SetReferenceFor("Kids", pDoc, pDoc->AddIndirectObject(kids));
+  pageNode->SetIntegerFor("Count", count);
+  uint32_t pageNodeRef = pDoc->AddIndirectObject(pageNode);
+  for (size_t i = 0; i < kids->GetCount(); i++)
+    kids->GetDictAt(i)->SetReferenceFor("Parent", pDoc, pageNodeRef);
+  return pageNode;
+}
+
+CPDF_Dictionary* CreateNumberedPage(size_t number) {
+  CPDF_Dictionary* page = new CPDF_Dictionary();
+  page->SetStringFor("Type", "Page");
+  page->SetIntegerFor("PageNumbering", number);
+  return page;
+}
+
+}  // namespace
+
+class CPDF_DocumentTest {
+ public:
+  CPDF_Document* SetUpTest() {
+    CPDF_ModuleMgr* module_mgr = CPDF_ModuleMgr::Get();
+    module_mgr->InitPageModule();
+    CPDF_Document* testDoc = new CPDF_Document(std::unique_ptr<CPDF_Parser>());

[Tom Sepez, 2016/10/21 21:31:40]

Are you sure you don't want to inherit from CPDF_Document instead?
Then all this can happen in its ctor.

I think you can just pass nullptr here and the unique_ptr ctor is implicit.

[npm, 2016/10/21 22:12:04]

Done.

+
+    CPDF_Dictionary* pages[7];

[Tom Sepez, 2016/10/21 21:31:40]

nit: probably don't need this local, later on just 

testDoc->AddIndirectObject(CreateNumberedPage(0));

[npm, 2016/10/21 22:12:04]

Done.

+    for (size_t i = 0; i < 7; i++)
+      pages[i] = CreateNumberedPage(i);
+    CPDF_Array* zeroToTwo = new CPDF_Array();
+    zeroToTwo->AddReference(testDoc, testDoc->AddIndirectObject(pages[0]));
+    zeroToTwo->AddReference(testDoc, testDoc->AddIndirectObject(pages[1]));
+    zeroToTwo->AddReference(testDoc, testDoc->AddIndirectObject(pages[2]));
+    CPDF_Dictionary* branch1 = CreatePageTreeNode(zeroToTwo, testDoc, 3);
+
+    CPDF_Array* zeroToThree = new CPDF_Array();
+    zeroToThree->AddReference(testDoc, branch1->GetObjNum());
+    zeroToThree->AddReference(testDoc, testDoc->AddIndirectObject(pages[3]));
+    CPDF_Dictionary* branch2 = CreatePageTreeNode(zeroToThree, testDoc, 4);
+
+    CPDF_Array* fourFive = new CPDF_Array();
+    fourFive->AddReference(testDoc, testDoc->AddIndirectObject(pages[4]));
+    fourFive->AddReference(testDoc, testDoc->AddIndirectObject(pages[5]));
+    CPDF_Dictionary* branch3 = CreatePageTreeNode(fourFive, testDoc, 2);
+
+    CPDF_Array* justSix = new CPDF_Array();
+    justSix->AddReference(testDoc, testDoc->AddIndirectObject(pages[6]));
+    CPDF_Dictionary* branch4 = CreatePageTreeNode(justSix, testDoc, 1);
+
+    CPDF_Array* allPages = new CPDF_Array();
+    allPages->AddReference(testDoc, branch2->GetObjNum());
+    allPages->AddReference(testDoc, branch3->GetObjNum());
+    allPages->AddReference(testDoc, branch4->GetObjNum());
+    CPDF_Dictionary* pagesDict = CreatePageTreeNode(allPages, testDoc, 7);
+
+    CPDF_Dictionary* root = new CPDF_Dictionary();
+    root->SetReferenceFor("Pages", testDoc,
+                          testDoc->AddIndirectObject(pagesDict));
+    testDoc->m_pRootDict = root;
+    testDoc->m_PageList.SetSize(7);
+    return testDoc;
+  }
+};
+
+TEST(cpdf_document, GetPages) {
+  CPDF_DocumentTest test;
+  CPDF_Document* document = test.SetUpTest();
+  for (int i = 0; i < 7; i++) {
+    CPDF_Dictionary* page = document->GetPage(i);
+    ASSERT_TRUE(page);

[Tom Sepez, 2016/10/21 21:31:40]

probably don't need this one, segv on next line etc.

[npm, 2016/10/21 21:46:00]

I thought we prefer not to crash if possible (ie to run all the tests)

[Tom Sepez, 2016/10/21 21:48:33]

Acknowledged.  Let's leave it then

+    ASSERT_TRUE(page->GetObjectFor("PageNumbering"));

[Tom Sepez, 2016/10/21 21:31:40]

probably should be expect_true.

[npm, 2016/10/21 21:46:00]

Ditto: if this is expect, then it will crash on the next expect_eq. In
that case, might as well get rid of the assert_true altogether.

+    EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
+  }
+  CPDF_Dictionary* page = document->GetPage(7);
+  EXPECT_FALSE(page);
+}
+
+TEST(cpdf_document, GetPagesReverseOrder) {
+  CPDF_DocumentTest test;
+  CPDF_Document* document = test.SetUpTest();
+  for (int i = 6; i >= 0; i--) {
+    CPDF_Dictionary* page = document->GetPage(i);
+    ASSERT_TRUE(page);
+    ASSERT_TRUE(page->GetObjectFor("PageNumbering"));
+    EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
+  }
+  CPDF_Dictionary* page = document->GetPage(7);
+  EXPECT_FALSE(page);
+}