1 // Copyright 2017 The PDFium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "core/fpdfapi/parser/cpdf_object_walker.h"
6
7 #include <sstream>
8 #include <string>
9 #include <utility>
10
11 #include "core/fpdfapi/parser/cpdf_array.h"
12 #include "core/fpdfapi/parser/cpdf_boolean.h"
13 #include "core/fpdfapi/parser/cpdf_dictionary.h"
14 #include "core/fpdfapi/parser/cpdf_name.h"
15 #include "core/fpdfapi/parser/cpdf_null.h"
16 #include "core/fpdfapi/parser/cpdf_number.h"
17 #include "core/fpdfapi/parser/cpdf_reference.h"
18 #include "core/fpdfapi/parser/cpdf_stream.h"
19 #include "core/fpdfapi/parser/cpdf_string.h"
20 #include "testing/gtest/include/gtest/gtest.h"
21
22 namespace {
23
Walk(RetainPtr<CPDF_Object> object)24 std::string Walk(RetainPtr<CPDF_Object> object) {
25 std::ostringstream result;
26 CPDF_ObjectWalker walker(std::move(object));
27 while (RetainPtr<const CPDF_Object> obj = walker.GetNext()) {
28 if (obj->IsDictionary())
29 result << " Dict";
30 else if (obj->IsArray())
31 result << " Arr";
32 else if (obj->IsString())
33 result << " Str";
34 else if (obj->IsBoolean())
35 result << " Bool";
36 else if (obj->IsStream())
37 result << " Stream";
38 else if (obj->IsReference())
39 result << " Ref";
40 else if (obj->IsNumber())
41 result << " Num";
42 else if (obj->IsNull())
43 result << " Null";
44 else
45 result << " Unknown";
46 }
47 std::string result_str = result.str();
48 if (!result_str.empty()) {
49 result_str.erase(result_str.begin()); // remove start space
50 }
51 return result_str;
52 }
53
54 } // namespace
55
TEST(ObjectWalkerTest,Simple)56 TEST(ObjectWalkerTest, Simple) {
57 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Null>()), "Null");
58 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Dictionary>()), "Dict");
59 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Array>()), "Arr");
60 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_String>()), "Str");
61 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Boolean>()), "Bool");
62 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Stream>()), "Stream");
63 EXPECT_EQ(Walk(pdfium::MakeRetain<CPDF_Reference>(nullptr, 0)), "Ref");
64 }
65
TEST(ObjectWalkerTest,CombinedObject)66 TEST(ObjectWalkerTest, CombinedObject) {
67 auto dict = pdfium::MakeRetain<CPDF_Dictionary>();
68 dict->SetFor("1", pdfium::MakeRetain<CPDF_String>());
69 dict->SetFor("2", pdfium::MakeRetain<CPDF_Boolean>());
70 auto array = pdfium::MakeRetain<CPDF_Array>();
71 array->Append(pdfium::MakeRetain<CPDF_Reference>(nullptr, 0));
72 array->Append(pdfium::MakeRetain<CPDF_Null>());
73 array->Append(
74 pdfium::MakeRetain<CPDF_Stream>(pdfium::MakeRetain<CPDF_Dictionary>()));
75 dict->SetFor("3", std::move(array));
76 // The last number for stream length.
77 EXPECT_EQ(Walk(dict), "Dict Str Bool Arr Ref Null Stream Dict Num");
78 }
79
TEST(ObjectWalkerTest,GetParent)80 TEST(ObjectWalkerTest, GetParent) {
81 auto level_4 = pdfium::MakeRetain<CPDF_Number>(0);
82 auto level_3 = pdfium::MakeRetain<CPDF_Dictionary>();
83 level_3->SetFor("Length", std::move(level_4));
84 auto level_2 = pdfium::MakeRetain<CPDF_Stream>(std::move(level_3));
85 auto level_1 = pdfium::MakeRetain<CPDF_Array>();
86 level_1->Append(std::move(level_2));
87 auto level_0 = pdfium::MakeRetain<CPDF_Dictionary>();
88 level_0->SetFor("Array", std::move(level_1));
89
90 // We have <</Array [ stream( << /Length 0 >>) ]>>
91 // In this case each step will increase depth.
92 // And on each step the prev object should be parent for current.
93 RetainPtr<const CPDF_Object> cur_parent;
94 CPDF_ObjectWalker walker(level_0);
95 while (RetainPtr<const CPDF_Object> obj = walker.GetNext()) {
96 EXPECT_EQ(cur_parent, walker.GetParent());
97 cur_parent = std::move(obj);
98 }
99 }
100
TEST(ObjectWalkerTest,SkipWalkIntoCurrentObject)101 TEST(ObjectWalkerTest, SkipWalkIntoCurrentObject) {
102 auto root_array = pdfium::MakeRetain<CPDF_Array>();
103 // Add 2 null objects into |root_array|. [ null1, null2 ]
104 root_array->AppendNew<CPDF_Null>();
105 root_array->AppendNew<CPDF_Null>();
106 // |root_array| will contain 4 null objects after this.
107 // [ null1, null2, [ null3, null4 ] ]
108 root_array->Append(root_array->Clone());
109
110 int non_array_objects = 0;
111 CPDF_ObjectWalker walker(root_array);
112 while (RetainPtr<const CPDF_Object> obj = walker.GetNext()) {
113 if (obj != root_array && obj->IsArray()) {
114 // skip other array except root.
115 walker.SkipWalkIntoCurrentObject();
116 }
117 if (!obj->IsArray())
118 ++non_array_objects;
119 }
120 // 2 objects from child array should be skipped.
121 EXPECT_EQ(2, non_array_objects);
122 }
123
TEST(ObjectWalkerTest,DictionaryKey)124 TEST(ObjectWalkerTest, DictionaryKey) {
125 auto dict = pdfium::MakeRetain<CPDF_Dictionary>();
126 dict->SetFor("1", pdfium::MakeRetain<CPDF_Null>());
127 dict->SetFor("2", pdfium::MakeRetain<CPDF_Null>());
128 dict->SetFor("3", pdfium::MakeRetain<CPDF_Null>());
129 dict->SetFor("4", pdfium::MakeRetain<CPDF_Null>());
130 dict->SetFor("5", pdfium::MakeRetain<CPDF_Null>());
131
132 CPDF_ObjectWalker walker(dict);
133 while (RetainPtr<const CPDF_Object> obj = walker.GetNext()) {
134 if (dict == obj) {
135 // Ignore root dictinary object
136 continue;
137 }
138 // Test that, dictionary key is correct.
139 EXPECT_EQ(walker.GetParent()->AsDictionary()->GetObjectFor(
140 walker.dictionary_key()),
141 obj);
142 }
143 }
144