Add iterators and unit tests for CPDF_Array class

Add iterators to enable range based for loop. Also add unit tests for recent modified functions.

Review URL: https://codereview.chromium.org/1878803002

4 files changed, 191 insertions, 0 deletions

diff --git a/BUILD.gn b/BUILD.gn
index e3131481ec..64f03e16c6 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1639,6 +1639,7 @@ test("pdfium_unittests") {
     "core/fpdfapi/fpdf_font/fpdf_font_unittest.cpp",
     "core/fpdfapi/fpdf_page/fpdf_page_parser_old_unittest.cpp",
     "core/fpdfapi/fpdf_page/fpdf_page_parser_unittest.cpp",
+    "core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp",
     "core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp",
     "core/fpdfapi/fpdf_parser/cpdf_parser_unittest.cpp",
     "core/fpdfapi/fpdf_parser/cpdf_simple_parser_unittest.cpp",
diff --git a/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp b/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp
new file mode 100644
index 0000000000..58642a610f
--- /dev/null
+++ b/core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp
@@ -0,0 +1,181 @@
+// 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/fpdf_parser/include/cpdf_array.h"
+#include "core/fpdfapi/fpdf_parser/include/cpdf_number.h"
+#include "core/fpdfapi/fpdf_parser/include/cpdf_reference.h"
+
+#include <memory>
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+using ScopedArray = std::unique_ptr<CPDF_Array, ReleaseDeleter<CPDF_Array>>;
+
+}  // namespace
+
+TEST(cpdf_array, RemoveAt) {
+  {
+    int elems[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+    ScopedArray arr(new CPDF_Array);
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      arr->AddInteger(elems[i]);
+    arr->RemoveAt(3, 3);
+    int expected[] = {1, 2, 3, 7, 8, 9, 10};
+    EXPECT_EQ(FX_ArraySize(expected), arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(expected); ++i)
+      EXPECT_EQ(expected[i], arr->GetIntegerAt(i));
+    arr->RemoveAt(4, 2);
+    int expected2[] = {1, 2, 3, 7, 10};
+    EXPECT_EQ(FX_ArraySize(expected2), arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(expected2); ++i)
+      EXPECT_EQ(expected2[i], arr->GetIntegerAt(i));
+  }
+  {
+    // When the range is out of bound, RemoveAt has no effect.
+    int elems[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+    ScopedArray arr(new CPDF_Array);
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      arr->AddInteger(elems[i]);
+    arr->RemoveAt(8, 5);
+    EXPECT_EQ(FX_ArraySize(elems), arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      EXPECT_EQ(elems[i], arr->GetIntegerAt(i));
+    arr->RemoveAt(0, 12);
+    EXPECT_EQ(FX_ArraySize(elems), arr->GetCount());
+    arr->RemoveAt(11, 1);
+    EXPECT_EQ(FX_ArraySize(elems), arr->GetCount());
+  }
+}
+
+TEST(cpdf_array, InsertAt) {
+  {
+    int elems[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+    ScopedArray arr(new CPDF_Array);
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      arr->InsertAt(i, new CPDF_Number(elems[i]));
+    EXPECT_EQ(FX_ArraySize(elems), arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      EXPECT_EQ(elems[i], arr->GetIntegerAt(i));
+    arr->InsertAt(3, new CPDF_Number(33));
+    arr->InsertAt(6, new CPDF_Number(55));
+    arr->InsertAt(12, new CPDF_Number(12));
+    int expected[] = {1, 2, 3, 33, 4, 5, 55, 6, 7, 8, 9, 10, 12};
+    EXPECT_EQ(FX_ArraySize(expected), arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(expected); ++i)
+      EXPECT_EQ(expected[i], arr->GetIntegerAt(i));
+  }
+  {
+    // When the position to insert is beyond the upper bound,
+    // an element is inserted at that position while other unfilled
+    // positions have nullptr.
+    int elems[] = {1, 2};
+    ScopedArray arr(new CPDF_Array);
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      arr->InsertAt(i, new CPDF_Number(elems[i]));
+    arr->InsertAt(10, new CPDF_Number(10));
+    EXPECT_EQ(11, arr->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      EXPECT_EQ(elems[i], arr->GetIntegerAt(i));
+    for (size_t i = FX_ArraySize(elems); i < 10; ++i)
+      EXPECT_EQ(nullptr, arr->GetObjectAt(i));
+    EXPECT_EQ(10, arr->GetIntegerAt(10));
+  }
+}
+
+TEST(cpdf_array, Clone) {
+  {
+    // Basic case.
+    int elems[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+    ScopedArray arr(new CPDF_Array);
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+      arr->InsertAt(i, new CPDF_Number(elems[i]));
+    ScopedArray arr2(arr->Clone()->AsArray());
+    EXPECT_EQ(arr->GetCount(), arr2->GetCount());
+    for (size_t i = 0; i < FX_ArraySize(elems); ++i) {
+      // Clone() always create new objects.
+      EXPECT_NE(arr->GetObjectAt(i), arr2->GetObjectAt(i));
+      EXPECT_EQ(arr->GetIntegerAt(i), arr2->GetIntegerAt(i));
+    }
+  }
+  {
+    // Clone() with and without dereferencing reference objects.
+    static const size_t kNumOfRows = 3;
+    static const size_t kNumOfRowElems = 5;
+    int elems[kNumOfRows][kNumOfRowElems] = {
+        {1, 2, 3, 4, 5}, {10, 9, 8, 7, 6}, {11, 12, 13, 14, 15}};
+    ScopedArray arr(new CPDF_Array);
+    // Indirect references to indirect objects.
+    std::unique_ptr<CPDF_IndirectObjectHolder> obj_holder(
+        new CPDF_IndirectObjectHolder(nullptr));
+    for (size_t i = 0; i < kNumOfRows; ++i) {
+      CPDF_Array* arr_elem = new CPDF_Array;
+      for (size_t j = 0; j < kNumOfRowElems; ++j) {
+        CPDF_Number* obj = new CPDF_Number(elems[i][j]);
+        // Starts object number from 1.
+        int obj_num = i * kNumOfRowElems + j + 1;
+        obj_holder->InsertIndirectObject(obj_num, obj);
+        arr_elem->InsertAt(j, new CPDF_Reference(obj_holder.get(), obj_num),
+                           obj_holder.get());
+      }
+      arr->InsertAt(i, arr_elem);
+    }
+    ASSERT_EQ(kNumOfRows, arr->GetCount());
+    // Not dereferencing reference objects means just creating new references
+    // instead of new copies of direct objects.
+    ScopedArray arr1(arr->Clone(FALSE)->AsArray());
+    EXPECT_EQ(arr->GetCount(), arr1->GetCount());
+    // Dereferencing reference objects creates new copies of direct objects.
+    ScopedArray arr2(arr->Clone(TRUE)->AsArray());
+    EXPECT_EQ(arr->GetCount(), arr2->GetCount());
+    for (size_t i = 0; i < kNumOfRows; ++i) {
+      CPDF_Array* arr_elem = arr->GetObjectAt(i)->AsArray();
+      CPDF_Array* arr1_elem = arr1->GetObjectAt(i)->AsArray();
+      CPDF_Array* arr2_elem = arr2->GetObjectAt(i)->AsArray();
+      EXPECT_NE(arr_elem, arr1_elem);
+      EXPECT_NE(arr_elem, arr2_elem);
+      for (size_t j = 0; j < kNumOfRowElems; ++j) {
+        auto elem_obj = arr_elem->GetObjectAt(j);
+        auto elem_obj1 = arr1_elem->GetObjectAt(j);
+        auto elem_obj2 = arr2_elem->GetObjectAt(j);
+        // Results from not deferencing reference objects.
+        EXPECT_NE(elem_obj, elem_obj1);
+        EXPECT_TRUE(elem_obj1->IsReference());
+        EXPECT_EQ(elem_obj->GetDirect(), elem_obj1->GetDirect());
+        EXPECT_EQ(elem_obj->GetInteger(), elem_obj1->GetInteger());
+        // Results from deferencing reference objects.
+        EXPECT_NE(elem_obj, elem_obj2);
+        EXPECT_TRUE(elem_obj2->IsNumber());
+        EXPECT_NE(elem_obj->GetDirect(), elem_obj2);
+        EXPECT_EQ(elem_obj->GetObjNum(), elem_obj2->GetObjNum());
+        EXPECT_EQ(elem_obj->GetInteger(), elem_obj2->GetInteger());
+      }
+    }
+    arr.reset();
+    ASSERT_EQ(kNumOfRows, arr1->GetCount());
+    for (size_t i = 0; i < kNumOfRows; ++i) {
+      for (size_t j = 0; j < kNumOfRowElems; ++j) {
+        // Results from not deferencing reference objects.
+        auto elem_obj1 = arr1->GetObjectAt(i)->AsArray()->GetObjectAt(j);
+        EXPECT_TRUE(elem_obj1->IsReference());
+        EXPECT_EQ(elems[i][j], elem_obj1->GetInteger());
+        // Results from deferencing reference objects.
+        EXPECT_EQ(elems[i][j],
+                  arr2->GetObjectAt(i)->AsArray()->GetIntegerAt(j));
+      }
+    }
+  }
+}
+
+TEST(cpdf_array, Iterator) {
+  int elems[] = {-23, -11,     3,         455,   2345877,
+                 0,   7895330, -12564334, 10000, -100000};
+  ScopedArray arr(new CPDF_Array);
+  for (size_t i = 0; i < FX_ArraySize(elems); ++i)
+    arr->InsertAt(i, new CPDF_Number(elems[i]));
+  size_t index = 0;
+  for (const auto& it : *arr)
+    EXPECT_EQ(elems[index++], it->AsNumber()->GetInteger());
+}
diff --git a/core/fpdfapi/fpdf_parser/include/cpdf_array.h b/core/fpdfapi/fpdf_parser/include/cpdf_array.h
index ac3bf41b45..dfe03b9d70 100644
--- a/core/fpdfapi/fpdf_parser/include/cpdf_array.h
+++ b/core/fpdfapi/fpdf_parser/include/cpdf_array.h
@@ -16,6 +16,9 @@
 
 class CPDF_Array : public CPDF_Object {
  public:
+  using iterator = std::vector<CPDF_Object*>::iterator;
+  using const_iterator = std::vector<CPDF_Object*>::const_iterator;
+
   CPDF_Array();
 
   // CPDF_Object.
@@ -57,6 +60,11 @@ class CPDF_Array : public CPDF_Object {
     AddReference(pDoc, obj->GetObjNum());
   }
 
+  iterator begin() { return m_Objects.begin(); }
+  iterator end() { return m_Objects.end(); }
+  const_iterator begin() const { return m_Objects.begin(); }
+  const_iterator end() const { return m_Objects.end(); }
+
  protected:
   ~CPDF_Array() override;
 
diff --git a/pdfium.gyp b/pdfium.gyp
index d4b22bd918..c43e9a9324 100644
--- a/pdfium.gyp
+++ b/pdfium.gyp
@@ -930,6 +930,7 @@
         'core/fpdfapi/fpdf_font/fpdf_font_unittest.cpp',
         'core/fpdfapi/fpdf_page/fpdf_page_parser_unittest.cpp',
         'core/fpdfapi/fpdf_page/fpdf_page_parser_old_unittest.cpp',
+        'core/fpdfapi/fpdf_parser/cpdf_array_unittest.cpp',
         'core/fpdfapi/fpdf_parser/cpdf_object_unittest.cpp',
         'core/fpdfapi/fpdf_parser/cpdf_parser_unittest.cpp',
         'core/fpdfapi/fpdf_parser/cpdf_simple_parser_unittest.cpp',