Add regression tests for popup appearance generation

Repeated annotation list creation generates appearances for closed
popups and adds document-owned indirect objects on each iteration.
Record this behavior with TODOs for the expected corrections.

Also verify opening, closing, and reopening popups through both drawing
paths, including the rendered pixels. The following fix will defer
appearance generation and update the incorrect expectations.

Bug: 42270200
Change-Id: I82384c0f2e920373fb87f52bba2539bb786009f1
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/159670
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

AUTHORS

diff --git a/AUTHORS b/AUTHORS
index c8141c9..0d44ac7 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -34,6 +34,7 @@
 Jimin Lee <cliceleee@gmail.com>
 Justin Pierce <brkfstmnchr@gmail.com>
 Ke Liu <stackexploit@gmail.com>
+Kei Kamikawa <x00.x7f.x86@gmail.com>
 Luật Nguyễn <manhluat93.php@gmail.com>
 Manuel Geißer <geisserml@gmail.com>
 Matt Jolly <kangie@gentoo.org>

core/fpdfdoc/cpdf_annotlist_unittest.cpp

diff --git a/core/fpdfdoc/cpdf_annotlist_unittest.cpp b/core/fpdfdoc/cpdf_annotlist_unittest.cpp
index a59f959..d5588de 100644
--- a/core/fpdfdoc/cpdf_annotlist_unittest.cpp
+++ b/core/fpdfdoc/cpdf_annotlist_unittest.cpp
@@ -17,11 +17,15 @@
 #include "core/fpdfapi/parser/cpdf_name.h"
 #include "core/fpdfapi/parser/cpdf_string.h"
 #include "core/fpdfapi/parser/cpdf_test_document.h"
+#include "core/fpdfapi/render/cpdf_rendercontext.h"
 #include "core/fpdfdoc/cpdf_annot.h"
 #include "core/fxcrt/bytestring.h"
 #include "core/fxcrt/compiler_specific.h"
 #include "core/fxcrt/retain_ptr.h"
 #include "core/fxcrt/widestring.h"
+#include "core/fxge/cfx_renderdevice.h"
+#include "core/fxge/dib/cfx_dibitmap.h"
+#include "core/fxge/dib/fx_dib.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
@@ -71,6 +75,10 @@
       pdfium::annotation::kContents);
 }
 
+FX_ARGB GetCenterPixel(const CFX_DIBitmap* bitmap) {
+  return FXARGB_GetDIB(bitmap->GetScanline(100).subspan<400, 4>());
+}
+
 }  // namespace
 
 TEST_F(CPDFAnnotListTest, CreatePopupAnnotFromPdfEncoded) {
@@ -124,3 +132,71 @@
 
   EXPECT_EQ(1u, list.Count());
 }
+
+TEST_F(CPDFAnnotListTest, ClosedPopupAppearanceObjects) {
+  AddTextAnnotation("Regression comment");
+  {
+    CPDF_AnnotList list(page_);
+    ASSERT_EQ(2u, list.Count());
+    EXPECT_TRUE(list.GetAt(0)->GetAnnotDict()->KeyExist("AP"));
+    // TODO(crbug.com/42270200): Closed popups should not have an appearance.
+    EXPECT_TRUE(list.GetAt(1)->GetAnnotDict()->KeyExist("AP"));
+  }
+  const uint32_t object_count = document_->GetLastObjNum();
+  for (int i = 0; i < 30; ++i) {
+    CPDF_AnnotList list(page_);
+    EXPECT_TRUE(list.GetAt(1)->GetAnnotDict()->KeyExist("AP"));
+    // TODO(crbug.com/42270200): Rebuilding the list should not add objects.
+    EXPECT_EQ(object_count + 2 * (i + 1), document_->GetLastObjNum());
+  }
+}
+
+class CPDFPopupRenderTest : public CPDFAnnotListTest,
+                            public testing::WithParamInterface<bool> {
+ protected:
+  bool UseRenderContext() const { return GetParam(); }
+
+  bool DrawPopup(CPDF_Annot* popup, CFX_RenderDevice* device) {
+    device->Clear(0xffffffff);
+    const CFX_Matrix matrix;
+    if (!UseRenderContext()) {
+      return popup->DrawAppearance(page_.Get(), device, matrix,
+                                   CPDF_Annot::AppearanceMode::kNormal);
+    }
+    CPDF_RenderContext context(document_.get(), nullptr, nullptr);
+    const bool result = popup->DrawInContext(
+        page_.Get(), &context, matrix, CPDF_Annot::AppearanceMode::kNormal);
+    context.Render(device, nullptr, nullptr, nullptr);
+    return result;
+  }
+};
+
+TEST_P(CPDFPopupRenderTest, PopupRendering) {
+  AddTextAnnotation("Regression comment");
+  CPDF_AnnotList list(page_);
+  ASSERT_EQ(2u, list.Count());
+  CPDF_Annot* popup = list.GetAt(1);
+  ASSERT_EQ(CPDF_Annot::Subtype::POPUP, popup->GetSubtype());
+  // TODO(crbug.com/42270200): Generate the appearance only when opened.
+  EXPECT_TRUE(popup->GetAnnotDict()->KeyExist("AP"));
+  auto device =
+      CFX_RenderDevice::CreateForNewBitmap(256, 256, FXDIB_Format::kBgra);
+  ASSERT_TRUE(device);
+  RetainPtr<CFX_DIBitmap> bitmap = device->GetBitmap();
+  EXPECT_FALSE(DrawPopup(popup, device.get()));
+  EXPECT_EQ(0xffffffffu, GetCenterPixel(bitmap.Get()));
+  popup->SetOpenState(true);
+  EXPECT_TRUE(DrawPopup(popup, device.get()));
+  EXPECT_EQ(0xffffff00u, GetCenterPixel(bitmap.Get()));
+  ASSERT_TRUE(popup->GetAnnotDict()->KeyExist("AP"));
+  const uint32_t object_count = document_->GetLastObjNum();
+  popup->SetOpenState(false);
+  EXPECT_FALSE(DrawPopup(popup, device.get()));
+  EXPECT_EQ(0xffffffffu, GetCenterPixel(bitmap.Get()));
+  popup->SetOpenState(true);
+  EXPECT_TRUE(DrawPopup(popup, device.get()));
+  EXPECT_EQ(0xffffff00u, GetCenterPixel(bitmap.Get()));
+  EXPECT_EQ(object_count, document_->GetLastObjNum());
+}
+
+INSTANTIATE_TEST_SUITE_P(All, CPDFPopupRenderTest, testing::Bool());