Rename fpdfsdk/fpdf* files to be consistent

This CL makes the fpdfsdk/fpdf* files to be consistently prefixed with
fpdf_ instead of randomly dropping the _.

Change-Id: I23e3c8a0831b56bcd17c788d9fe874b2ab8b24fc
Reviewed-on: https://pdfium-review.googlesource.com/29390
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 1458 insertions, 0 deletions

diff --git a/fpdfsdk/fpdf_annot_embeddertest.cpp b/fpdfsdk/fpdf_annot_embeddertest.cpp
new file mode 100644
index 0000000000..b97193db46
--- /dev/null
+++ b/fpdfsdk/fpdf_annot_embeddertest.cpp
@@ -0,0 +1,1458 @@
+// Copyright 2017 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 <cwchar>
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "core/fxcrt/fx_system.h"
+#include "public/cpp/fpdf_deleters.h"
+#include "public/fpdf_annot.h"
+#include "public/fpdf_edit.h"
+#include "public/fpdfview.h"
+#include "testing/embedder_test.h"
+#include "testing/gmock/include/gmock/gmock-matchers.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+static constexpr char kContentsKey[] = "Contents";
+
+class FPDFAnnotEmbeddertest : public EmbedderTest {};
+
+std::wstring BufferToWString(const std::vector<char>& buf) {
+  return GetPlatformWString(reinterpret_cast<FPDF_WIDESTRING>(buf.data()));
+}
+
+std::string BufferToString(const std::vector<char>& buf) {
+  return GetPlatformString(reinterpret_cast<FPDF_WIDESTRING>(buf.data()));
+}
+
+TEST_F(FPDFAnnotEmbeddertest, RenderAnnotWithOnlyRolloverAP) {
+  // Open a file with one annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_rollover_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  // This annotation has a malformed appearance stream, which does not have its
+  // normal appearance defined, only its rollover appearance. In this case, its
+  // normal appearance should be generated, allowing the highlight annotation to
+  // still display.
+  std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+      RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+  CompareBitmap(bitmap.get(), 612, 792, "dc98f06da047bd8aabfa99562d2cbd1e");
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, RenderMultilineMarkupAnnotWithoutAP) {
+  const char md5_hash[] = "76512832d88017668d9acc7aacd13dae";
+  // Open a file with multiline markup annotations.
+  ASSERT_TRUE(OpenDocument("annotation_markup_multiline_no_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+      RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+  CompareBitmap(bitmap.get(), 595, 842, md5_hash);
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, ExtractHighlightLongContent) {
+  // Open a file with one annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_long_content.pdf"));
+  // TODO(thestig): This test should use LoadPage() and UnloadPage(), but one of
+  // the FORM API calls in LoadPage() makes this test fail. So use
+  // FPDF_LoadPage() and FPDF_ClosePage() for now.
+  FPDF_PAGE page = FPDF_LoadPage(document(), 0);
+  ASSERT_TRUE(page);
+
+  // Check that there is a total of 1 annotation on its first page.
+  EXPECT_EQ(1, FPDFPage_GetAnnotCount(page));
+
+  // Check that the annotation is of type "highlight".
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_HIGHLIGHT, FPDFAnnot_GetSubtype(annot.get()));
+
+    // Check that the annotation color is yellow.
+    unsigned int R;
+    unsigned int G;
+    unsigned int B;
+    unsigned int A;
+    ASSERT_TRUE(FPDFAnnot_GetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, &R,
+                                   &G, &B, &A));
+    EXPECT_EQ(255u, R);
+    EXPECT_EQ(255u, G);
+    EXPECT_EQ(0u, B);
+    EXPECT_EQ(255u, A);
+
+    // Check that the author is correct.
+    static constexpr char kAuthorKey[] = "T";
+    EXPECT_EQ(FPDF_OBJECT_STRING,
+              FPDFAnnot_GetValueType(annot.get(), kAuthorKey));
+    unsigned long len =
+        FPDFAnnot_GetStringValue(annot.get(), kAuthorKey, nullptr, 0);
+    std::vector<char> buf(len);
+    EXPECT_EQ(28u, FPDFAnnot_GetStringValue(annot.get(), kAuthorKey, buf.data(),
+                                            len));
+    EXPECT_STREQ(L"Jae Hyun Park", BufferToWString(buf).c_str());
+
+    // Check that the content is correct.
+    EXPECT_EQ(FPDF_OBJECT_STRING,
+              FPDFAnnot_GetValueType(annot.get(), kContentsKey));
+    len = FPDFAnnot_GetStringValue(annot.get(), kContentsKey, nullptr, 0);
+    buf.clear();
+    buf.resize(len);
+    EXPECT_EQ(2690u, FPDFAnnot_GetStringValue(annot.get(), kContentsKey,
+                                              buf.data(), len));
+    const wchar_t contents[] =
+        L"This is a note for that highlight annotation. Very long highlight "
+        "annotation. Long long long Long long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long longLong long longLong long longLong long longLong long "
+        "longLong long long. END";
+    EXPECT_STREQ(contents, BufferToWString(buf).c_str());
+
+    // Check that the quadpoints are correct.
+    FS_QUADPOINTSF quadpoints;
+    ASSERT_TRUE(FPDFAnnot_GetAttachmentPoints(annot.get(), &quadpoints));
+    EXPECT_EQ(115.802643f, quadpoints.x1);
+    EXPECT_EQ(718.913940f, quadpoints.y1);
+    EXPECT_EQ(157.211182f, quadpoints.x4);
+    EXPECT_EQ(706.264465f, quadpoints.y4);
+  }
+  FPDF_ClosePage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, ExtractInkMultiple) {
+  // Open a file with three annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_ink_multiple.pdf"));
+  // TODO(thestig): This test should use LoadPage() and UnloadPage(), but one of
+  // the FORM API calls in LoadPage() makes this test fail. So use
+  // FPDF_LoadPage() and FPDF_ClosePage() for now.
+  FPDF_PAGE page = FPDF_LoadPage(document(), 0);
+  ASSERT_TRUE(page);
+
+  // Check that there is a total of 3 annotation on its first page.
+  EXPECT_EQ(3, FPDFPage_GetAnnotCount(page));
+
+  {
+    // Check that the third annotation is of type "ink".
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_INK, FPDFAnnot_GetSubtype(annot.get()));
+
+    // Check that the annotation color is blue with opacity.
+    unsigned int R;
+    unsigned int G;
+    unsigned int B;
+    unsigned int A;
+    ASSERT_TRUE(FPDFAnnot_GetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, &R,
+                                   &G, &B, &A));
+    EXPECT_EQ(0u, R);
+    EXPECT_EQ(0u, G);
+    EXPECT_EQ(255u, B);
+    EXPECT_EQ(76u, A);
+
+    // Check that there is no content.
+    EXPECT_EQ(2u,
+              FPDFAnnot_GetStringValue(annot.get(), kContentsKey, nullptr, 0));
+
+    // Check that the rectange coordinates are correct.
+    // Note that upon rendering, the rectangle coordinates will be adjusted.
+    FS_RECTF rect;
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_EQ(351.820404f, rect.left);
+    EXPECT_EQ(583.830688f, rect.bottom);
+    EXPECT_EQ(475.336090f, rect.right);
+    EXPECT_EQ(681.535034f, rect.top);
+  }
+  FPDF_ClosePage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddIllegalSubtypeAnnotation) {
+  // Open a file with one annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_long_content.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  // Add an annotation with an illegal subtype.
+  ASSERT_FALSE(FPDFPage_CreateAnnot(page, -1));
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddFirstTextAnnotation) {
+  // Open a file with no annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("hello_world.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(0, FPDFPage_GetAnnotCount(page));
+
+  {
+    // Add a text annotation to the page.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_CreateAnnot(page, FPDF_ANNOT_TEXT));
+    ASSERT_TRUE(annot);
+
+    // Check that there is now 1 annotations on this page.
+    EXPECT_EQ(1, FPDFPage_GetAnnotCount(page));
+
+    // Check that the subtype of the annotation is correct.
+    EXPECT_EQ(FPDF_ANNOT_TEXT, FPDFAnnot_GetSubtype(annot.get()));
+  }
+
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_TEXT, FPDFAnnot_GetSubtype(annot.get()));
+
+    // Set the color of the annotation.
+    ASSERT_TRUE(FPDFAnnot_SetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, 51,
+                                   102, 153, 204));
+    // Check that the color has been set correctly.
+    unsigned int R;
+    unsigned int G;
+    unsigned int B;
+    unsigned int A;
+    ASSERT_TRUE(FPDFAnnot_GetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, &R,
+                                   &G, &B, &A));
+    EXPECT_EQ(51u, R);
+    EXPECT_EQ(102u, G);
+    EXPECT_EQ(153u, B);
+    EXPECT_EQ(204u, A);
+
+    // Change the color of the annotation.
+    ASSERT_TRUE(FPDFAnnot_SetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, 204,
+                                   153, 102, 51));
+    // Check that the color has been set correctly.
+    ASSERT_TRUE(FPDFAnnot_GetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, &R,
+                                   &G, &B, &A));
+    EXPECT_EQ(204u, R);
+    EXPECT_EQ(153u, G);
+    EXPECT_EQ(102u, B);
+    EXPECT_EQ(51u, A);
+
+    // Set the annotation rectangle.
+    FS_RECTF rect;
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_EQ(0.f, rect.left);
+    EXPECT_EQ(0.f, rect.right);
+    rect.left = 35;
+    rect.bottom = 150;
+    rect.right = 53;
+    rect.top = 165;
+    ASSERT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+    // Check that the annotation rectangle has been set correctly.
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_EQ(35.f, rect.left);
+    EXPECT_EQ(150.f, rect.bottom);
+    EXPECT_EQ(53.f, rect.right);
+    EXPECT_EQ(165.f, rect.top);
+
+    // Set the content of the annotation.
+    static constexpr wchar_t kContents[] =
+        L"Hello! This is a customized content.";
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> text =
+        GetFPDFWideString(kContents);
+    ASSERT_TRUE(
+        FPDFAnnot_SetStringValue(annot.get(), kContentsKey, text.get()));
+    // Check that the content has been set correctly.
+    unsigned long len =
+        FPDFAnnot_GetStringValue(annot.get(), kContentsKey, nullptr, 0);
+    std::vector<char> buf(len);
+    EXPECT_EQ(74u, FPDFAnnot_GetStringValue(annot.get(), kContentsKey,
+                                            buf.data(), len));
+    EXPECT_STREQ(kContents, BufferToWString(buf).c_str());
+  }
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddAndSaveUnderlineAnnotation) {
+  // Open a file with one annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_long_content.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  // Check that there is a total of one annotation on its first page, and verify
+  // its quadpoints.
+  EXPECT_EQ(1, FPDFPage_GetAnnotCount(page));
+  FS_QUADPOINTSF quadpoints;
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+    ASSERT_TRUE(FPDFAnnot_GetAttachmentPoints(annot.get(), &quadpoints));
+    EXPECT_EQ(115.802643f, quadpoints.x1);
+    EXPECT_EQ(718.913940f, quadpoints.y1);
+    EXPECT_EQ(157.211182f, quadpoints.x4);
+    EXPECT_EQ(706.264465f, quadpoints.y4);
+  }
+
+  // Add an underline annotation to the page and set its quadpoints.
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_CreateAnnot(page, FPDF_ANNOT_UNDERLINE));
+    ASSERT_TRUE(annot);
+    quadpoints.x1 = 140.802643f;
+    quadpoints.x3 = 140.802643f;
+    ASSERT_TRUE(FPDFAnnot_SetAttachmentPoints(annot.get(), &quadpoints));
+  }
+
+  // Save the document, closing the page and document.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  UnloadPage(page);
+
+  // Open the saved document.
+  const char md5[] = "dba153419f67b7c0c0e3d22d3e8910d5";
+
+  OpenSavedDocument();
+  page = LoadSavedPage(0);
+  VerifySavedRendering(page, 612, 792, md5);
+
+  // Check that the saved document has 2 annotations on the first page
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(page));
+
+  {
+    // Check that the second annotation is an underline annotation and verify
+    // its quadpoints.
+    std::unique_ptr<void, FPDFAnnotationDeleter> new_annot(
+        FPDFPage_GetAnnot(page, 1));
+    ASSERT_TRUE(new_annot);
+    EXPECT_EQ(FPDF_ANNOT_UNDERLINE, FPDFAnnot_GetSubtype(new_annot.get()));
+    FS_QUADPOINTSF new_quadpoints;
+    ASSERT_TRUE(
+        FPDFAnnot_GetAttachmentPoints(new_annot.get(), &new_quadpoints));
+    EXPECT_NEAR(quadpoints.x1, new_quadpoints.x1, 0.001f);
+    EXPECT_NEAR(quadpoints.y1, new_quadpoints.y1, 0.001f);
+    EXPECT_NEAR(quadpoints.x4, new_quadpoints.x4, 0.001f);
+    EXPECT_NEAR(quadpoints.y4, new_quadpoints.y4, 0.001f);
+  }
+
+  CloseSavedPage(page);
+  CloseSavedDocument();
+}
+
+TEST_F(FPDFAnnotEmbeddertest, ModifyRectQuadpointsWithAP) {
+#if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
+  const char md5_original[] = "63af8432fab95a67cdebb7cd0e514941";
+  const char md5_modified_highlight[] = "aec26075011349dec9bace891856b5f2";
+  const char md5_modified_square[] = "057f57a32be95975775e5ec513fdcb56";
+#elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
+  const char md5_original[] = "0e27376094f11490f74c65f3dc3a42c5";
+  const char md5_modified_highlight[] = "66f3caef3a7d488a4fa1ad37fc06310e";
+  const char md5_modified_square[] = "a456dad0bc6801ee2d6408a4394af563";
+#else
+  const char md5_original[] = "0e27376094f11490f74c65f3dc3a42c5";
+  const char md5_modified_highlight[] = "66f3caef3a7d488a4fa1ad37fc06310e";
+  const char md5_modified_square[] = "a456dad0bc6801ee2d6408a4394af563";
+#endif
+
+  // Open a file with four annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_square_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(4, FPDFPage_GetAnnotCount(page));
+
+  // Check that the original file renders correctly.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 612, 792, md5_original);
+  }
+
+  FS_RECTF rect;
+  FS_RECTF new_rect;
+
+  // Retrieve the highlight annotation which has its AP stream already defined.
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_HIGHLIGHT, FPDFAnnot_GetSubtype(annot.get()));
+
+    // Check that color cannot be set when an AP stream is defined already.
+    EXPECT_FALSE(FPDFAnnot_SetColor(annot.get(), FPDFANNOT_COLORTYPE_Color, 51,
+                                    102, 153, 204));
+
+    // Verify its attachment points.
+    FS_QUADPOINTSF quadpoints;
+    ASSERT_TRUE(FPDFAnnot_GetAttachmentPoints(annot.get(), &quadpoints));
+    EXPECT_NEAR(72.0000f, quadpoints.x1, 0.001f);
+    EXPECT_NEAR(720.792f, quadpoints.y1, 0.001f);
+    EXPECT_NEAR(132.055f, quadpoints.x4, 0.001f);
+    EXPECT_NEAR(704.796f, quadpoints.y4, 0.001f);
+
+    // Check that updating the attachment points would succeed.
+    quadpoints.x1 -= 50.f;
+    quadpoints.x2 -= 50.f;
+    quadpoints.x3 -= 50.f;
+    quadpoints.x4 -= 50.f;
+    ASSERT_TRUE(FPDFAnnot_SetAttachmentPoints(annot.get(), &quadpoints));
+    FS_QUADPOINTSF new_quadpoints;
+    ASSERT_TRUE(FPDFAnnot_GetAttachmentPoints(annot.get(), &new_quadpoints));
+    EXPECT_EQ(quadpoints.x1, new_quadpoints.x1);
+    EXPECT_EQ(quadpoints.y1, new_quadpoints.y1);
+    EXPECT_EQ(quadpoints.x4, new_quadpoints.x4);
+    EXPECT_EQ(quadpoints.y4, new_quadpoints.y4);
+
+    // Check that updating quadpoints does not change the annotation's position.
+    {
+      std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+          RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+      CompareBitmap(bitmap.get(), 612, 792, md5_original);
+    }
+
+    // Verify its annotation rectangle.
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(67.7299f, rect.left, 0.001f);
+    EXPECT_NEAR(704.296f, rect.bottom, 0.001f);
+    EXPECT_NEAR(136.325f, rect.right, 0.001f);
+    EXPECT_NEAR(721.292f, rect.top, 0.001f);
+
+    // Check that updating the rectangle would succeed.
+    rect.left -= 60.f;
+    rect.right -= 60.f;
+    ASSERT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &new_rect));
+    EXPECT_EQ(rect.right, new_rect.right);
+  }
+
+  // Check that updating the rectangle changes the annotation's position.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 612, 792, md5_modified_highlight);
+  }
+
+  {
+    // Retrieve the square annotation which has its AP stream already defined.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_SQUARE, FPDFAnnot_GetSubtype(annot.get()));
+
+    // Check that updating the rectangle would succeed.
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    rect.left += 70.f;
+    rect.right += 70.f;
+    ASSERT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &new_rect));
+    EXPECT_EQ(rect.right, new_rect.right);
+
+    // Check that updating the rectangle changes the square annotation's
+    // position.
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 612, 792, md5_modified_square);
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, CountAttachmentPoints) {
+  // Open a file with multiline markup annotations.
+  ASSERT_TRUE(OpenDocument("annotation_markup_multiline_no_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // This is a three line annotation.
+    EXPECT_EQ(3u, FPDFAnnot_CountAttachmentPoints(annot.get()));
+  }
+  UnloadPage(page);
+
+  // null annotation should return 0
+  EXPECT_EQ(0u, FPDFAnnot_CountAttachmentPoints(nullptr));
+}
+
+TEST_F(FPDFAnnotEmbeddertest, RemoveAnnotation) {
+  // Open a file with 3 annotations on its first page.
+  ASSERT_TRUE(OpenDocument("annotation_ink_multiple.pdf"));
+  // TODO(thestig): This test should use LoadPage() and UnloadPage(), but one of
+  // the FORM API calls in LoadPage() makes this test fail. So use
+  // FPDF_LoadPage() and FPDF_ClosePage() for now.
+  FPDF_PAGE page = FPDF_LoadPage(document(), 0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(3, FPDFPage_GetAnnotCount(page));
+
+  FS_RECTF rect;
+
+  // Check that the annotations have the expected rectangle coordinates.
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(86.1971f, rect.left, 0.001f);
+  }
+
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 1));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(149.8127f, rect.left, 0.001f);
+  }
+
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(351.8204f, rect.left, 0.001f);
+  }
+
+  // Check that nothing happens when attempting to remove an annotation with an
+  // out-of-bound index.
+  EXPECT_FALSE(FPDFPage_RemoveAnnot(page, 4));
+  EXPECT_FALSE(FPDFPage_RemoveAnnot(page, -1));
+  EXPECT_EQ(3, FPDFPage_GetAnnotCount(page));
+
+  // Remove the second annotation.
+  EXPECT_TRUE(FPDFPage_RemoveAnnot(page, 1));
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(page));
+  EXPECT_FALSE(FPDFPage_GetAnnot(page, 2));
+
+  // Save the document, closing the page and document.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  FPDF_ClosePage(page);
+
+  // TODO(npm): VerifySavedRendering changes annot rect dimensions by 1??
+  // Open the saved document.
+  std::string new_file = GetString();
+  FPDF_FILEACCESS file_access;
+  memset(&file_access, 0, sizeof(file_access));
+  file_access.m_FileLen = new_file.size();
+  file_access.m_GetBlock = GetBlockFromString;
+  file_access.m_Param = &new_file;
+  FPDF_DOCUMENT new_doc = FPDF_LoadCustomDocument(&file_access, nullptr);
+  ASSERT_TRUE(new_doc);
+  FPDF_PAGE new_page = FPDF_LoadPage(new_doc, 0);
+  ASSERT_TRUE(new_page);
+
+  // Check that the saved document has 2 annotations on the first page.
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(new_page));
+
+  // Check that the remaining 2 annotations are the original 1st and 3rd ones
+  // by verifying their rectangle coordinates.
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(new_page, 0));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(86.1971f, rect.left, 0.001f);
+  }
+
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(new_page, 1));
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &rect));
+    EXPECT_NEAR(351.8204f, rect.left, 0.001f);
+  }
+  FPDF_ClosePage(new_page);
+  FPDF_CloseDocument(new_doc);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddAndModifyPath) {
+#if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
+  const char md5_original[] = "c35408717759562d1f8bf33d317483d2";
+  const char md5_modified_path[] = "873b92ea83ccf006e58415d866ce145b";
+  const char md5_two_paths[] = "6f1f1c91f50240e9cc9d7c87c48b93a7";
+  const char md5_new_annot[] = "078bf58f939645ac305854f31ee9a828";
+#else
+  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
+  const char md5_modified_path[] = "5a4a6091cff648a4ece3ce7e245e3e38";
+  const char md5_two_paths[] = "d6e4072a4415cfc6ec17201fb6be0ee0";
+  const char md5_new_annot[] = "fc338b97bf66a656916c6198697a8a28";
+#endif
+
+  // Open a file with two annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(page));
+
+  // Check that the page renders correctly.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_original);
+  }
+
+  {
+    // Retrieve the stamp annotation which has its AP stream already defined.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that this annotation has one path object and retrieve it.
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+    ASSERT_EQ(32, FPDFPage_CountObjects(page));
+    FPDF_PAGEOBJECT path = FPDFAnnot_GetObject(annot.get(), 1);
+    EXPECT_FALSE(path);
+    path = FPDFAnnot_GetObject(annot.get(), 0);
+    EXPECT_EQ(FPDF_PAGEOBJ_PATH, FPDFPageObj_GetType(path));
+    EXPECT_TRUE(path);
+
+    // Modify the color of the path object.
+    EXPECT_TRUE(FPDFPath_SetStrokeColor(path, 0, 0, 0, 255));
+    EXPECT_TRUE(FPDFAnnot_UpdateObject(annot.get(), path));
+
+    // Check that the page with the modified annotation renders correctly.
+    {
+      std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+          RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+      CompareBitmap(bitmap.get(), 595, 842, md5_modified_path);
+    }
+
+    // Add a second path object to the same annotation.
+    FPDF_PAGEOBJECT dot = FPDFPageObj_CreateNewPath(7, 84);
+    EXPECT_TRUE(FPDFPath_BezierTo(dot, 9, 86, 10, 87, 11, 88));
+    EXPECT_TRUE(FPDFPath_SetStrokeColor(dot, 255, 0, 0, 100));
+    EXPECT_TRUE(FPDFPath_SetStrokeWidth(dot, 14));
+    EXPECT_TRUE(FPDFPath_SetDrawMode(dot, 0, 1));
+    EXPECT_TRUE(FPDFAnnot_AppendObject(annot.get(), dot));
+    EXPECT_EQ(2, FPDFAnnot_GetObjectCount(annot.get()));
+
+    // The object is in the annontation, not in the page, so the page object
+    // array should not change.
+    ASSERT_EQ(32, FPDFPage_CountObjects(page));
+
+    // Check that the page with an annotation with two paths renders correctly.
+    {
+      std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+          RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+      CompareBitmap(bitmap.get(), 595, 842, md5_two_paths);
+    }
+
+    // Delete the newly added path object.
+    EXPECT_TRUE(FPDFAnnot_RemoveObject(annot.get(), 1));
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+    ASSERT_EQ(32, FPDFPage_CountObjects(page));
+  }
+
+  // Check that the page renders the same as before.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_modified_path);
+  }
+
+  FS_RECTF rect;
+
+  {
+    // Create another stamp annotation and set its annotation rectangle.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_CreateAnnot(page, FPDF_ANNOT_STAMP));
+    ASSERT_TRUE(annot);
+    rect.left = 200.f;
+    rect.bottom = 400.f;
+    rect.right = 500.f;
+    rect.top = 600.f;
+    EXPECT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+
+    // Add a new path to the annotation.
+    FPDF_PAGEOBJECT check = FPDFPageObj_CreateNewPath(200, 500);
+    EXPECT_TRUE(FPDFPath_LineTo(check, 300, 400));
+    EXPECT_TRUE(FPDFPath_LineTo(check, 500, 600));
+    EXPECT_TRUE(FPDFPath_MoveTo(check, 350, 550));
+    EXPECT_TRUE(FPDFPath_LineTo(check, 450, 450));
+    EXPECT_TRUE(FPDFPath_SetStrokeColor(check, 0, 255, 255, 180));
+    EXPECT_TRUE(FPDFPath_SetStrokeWidth(check, 8.35f));
+    EXPECT_TRUE(FPDFPath_SetDrawMode(check, 0, 1));
+    EXPECT_TRUE(FPDFAnnot_AppendObject(annot.get(), check));
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+
+    // Check that the annotation's bounding box came from its rectangle.
+    FS_RECTF new_rect;
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &new_rect));
+    EXPECT_EQ(rect.left, new_rect.left);
+    EXPECT_EQ(rect.bottom, new_rect.bottom);
+    EXPECT_EQ(rect.right, new_rect.right);
+    EXPECT_EQ(rect.top, new_rect.top);
+  }
+
+  // Save the document, closing the page and document.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  UnloadPage(page);
+
+  // Open the saved document.
+  OpenSavedDocument();
+  page = LoadSavedPage(0);
+  VerifySavedRendering(page, 595, 842, md5_new_annot);
+
+  // Check that the document has a correct count of annotations and objects.
+  EXPECT_EQ(3, FPDFPage_GetAnnotCount(page));
+
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+
+    // Check that the new annotation's rectangle is as defined.
+    FS_RECTF new_rect;
+    ASSERT_TRUE(FPDFAnnot_GetRect(annot.get(), &new_rect));
+    EXPECT_EQ(rect.left, new_rect.left);
+    EXPECT_EQ(rect.bottom, new_rect.bottom);
+    EXPECT_EQ(rect.right, new_rect.right);
+    EXPECT_EQ(rect.top, new_rect.top);
+  }
+
+  CloseSavedPage(page);
+  CloseSavedDocument();
+}
+
+TEST_F(FPDFAnnotEmbeddertest, ModifyAnnotationFlags) {
+  // Open a file with an annotation and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_rollover_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  // Check that the page renders correctly.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 612, 792, "dc98f06da047bd8aabfa99562d2cbd1e");
+  }
+
+  {
+    // Retrieve the annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that the original flag values are as expected.
+    int flags = FPDFAnnot_GetFlags(annot.get());
+    EXPECT_FALSE(flags & FPDF_ANNOT_FLAG_HIDDEN);
+    EXPECT_TRUE(flags & FPDF_ANNOT_FLAG_PRINT);
+
+    // Set the HIDDEN flag.
+    flags |= FPDF_ANNOT_FLAG_HIDDEN;
+    EXPECT_TRUE(FPDFAnnot_SetFlags(annot.get(), flags));
+    flags = FPDFAnnot_GetFlags(annot.get());
+    EXPECT_TRUE(flags & FPDF_ANNOT_FLAG_HIDDEN);
+    EXPECT_TRUE(flags & FPDF_ANNOT_FLAG_PRINT);
+
+    // Check that the page renders correctly without rendering the annotation.
+    {
+      std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+          RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+      CompareBitmap(bitmap.get(), 612, 792, "1940568c9ba33bac5d0b1ee9558c76b3");
+    }
+
+    // Unset the HIDDEN flag.
+    EXPECT_TRUE(FPDFAnnot_SetFlags(annot.get(), FPDF_ANNOT_FLAG_NONE));
+    EXPECT_FALSE(FPDFAnnot_GetFlags(annot.get()));
+    flags &= ~FPDF_ANNOT_FLAG_HIDDEN;
+    EXPECT_TRUE(FPDFAnnot_SetFlags(annot.get(), flags));
+    flags = FPDFAnnot_GetFlags(annot.get());
+    EXPECT_FALSE(flags & FPDF_ANNOT_FLAG_HIDDEN);
+    EXPECT_TRUE(flags & FPDF_ANNOT_FLAG_PRINT);
+
+    // Check that the page renders correctly as before.
+    {
+      std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+          RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+      CompareBitmap(bitmap.get(), 612, 792, "dc98f06da047bd8aabfa99562d2cbd1e");
+    }
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddAndModifyImage) {
+#if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
+  const char md5_original[] = "c35408717759562d1f8bf33d317483d2";
+  const char md5_new_image[] = "ff012f5697436dfcaec25b32d1333596";
+  const char md5_modified_image[] = "86cf8cb2755a7a2046a543e66d9c1e61";
+#else
+  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
+  const char md5_new_image[] = "9ea8732dc9d579f68853f16892856208";
+  const char md5_modified_image[] = "74239d2a8c55c9de1dbb9cd8781895aa";
+#endif
+
+  // Open a file with two annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(page));
+
+  // Check that the page renders correctly.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_original);
+  }
+
+  constexpr int kBitmapSize = 200;
+  FPDF_BITMAP image_bitmap;
+
+  {
+    // Create a stamp annotation and set its annotation rectangle.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_CreateAnnot(page, FPDF_ANNOT_STAMP));
+    ASSERT_TRUE(annot);
+    FS_RECTF rect;
+    rect.left = 200.f;
+    rect.bottom = 600.f;
+    rect.right = 400.f;
+    rect.top = 800.f;
+    EXPECT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+
+    // Add a solid-color translucent image object to the new annotation.
+    image_bitmap = FPDFBitmap_Create(kBitmapSize, kBitmapSize, 1);
+    FPDFBitmap_FillRect(image_bitmap, 0, 0, kBitmapSize, kBitmapSize,
+                        0xeeeecccc);
+    EXPECT_EQ(kBitmapSize, FPDFBitmap_GetWidth(image_bitmap));
+    EXPECT_EQ(kBitmapSize, FPDFBitmap_GetHeight(image_bitmap));
+    FPDF_PAGEOBJECT image_object = FPDFPageObj_NewImageObj(document());
+    ASSERT_TRUE(FPDFImageObj_SetBitmap(&page, 0, image_object, image_bitmap));
+    ASSERT_TRUE(FPDFImageObj_SetMatrix(image_object, kBitmapSize, 0, 0,
+                                       kBitmapSize, 0, 0));
+    FPDFPageObj_Transform(image_object, 1, 0, 0, 1, 200, 600);
+    EXPECT_TRUE(FPDFAnnot_AppendObject(annot.get(), image_object));
+  }
+
+  // Check that the page renders correctly with the new image object.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_new_image);
+  }
+
+  {
+    // Retrieve the newly added stamp annotation and its image object.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+    FPDF_PAGEOBJECT image_object = FPDFAnnot_GetObject(annot.get(), 0);
+    EXPECT_EQ(FPDF_PAGEOBJ_IMAGE, FPDFPageObj_GetType(image_object));
+
+    // Modify the image in the new annotation.
+    FPDFBitmap_FillRect(image_bitmap, 0, 0, kBitmapSize, kBitmapSize,
+                        0xff000000);
+    ASSERT_TRUE(FPDFImageObj_SetBitmap(&page, 0, image_object, image_bitmap));
+    EXPECT_TRUE(FPDFAnnot_UpdateObject(annot.get(), image_object));
+  }
+
+  // Save the document, closing the page and document.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  UnloadPage(page);
+  FPDFBitmap_Destroy(image_bitmap);
+
+  // Test that the saved document renders the modified image object correctly.
+  VerifySavedDocument(595, 842, md5_modified_image);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, AddAndModifyText) {
+#if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
+  const char md5_original[] = "c35408717759562d1f8bf33d317483d2";
+  const char md5_new_text[] = "e5680ed048c2cfd9a1d27212cdf41286";
+  const char md5_modified_text[] = "79f5cfb0b07caaf936f65f6a7a57ce77";
+#else
+  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
+  const char md5_new_text[] = "00b14fa2dc1c90d1b0d034e1608efef5";
+  const char md5_modified_text[] = "076c8f24a09ddc0e49f7e758edead6f0";
+#endif
+
+  // Open a file with two annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(2, FPDFPage_GetAnnotCount(page));
+
+  // Check that the page renders correctly.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_original);
+  }
+
+  {
+    // Create a stamp annotation and set its annotation rectangle.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_CreateAnnot(page, FPDF_ANNOT_STAMP));
+    ASSERT_TRUE(annot);
+    FS_RECTF rect;
+    rect.left = 200.f;
+    rect.bottom = 550.f;
+    rect.right = 450.f;
+    rect.top = 650.f;
+    EXPECT_TRUE(FPDFAnnot_SetRect(annot.get(), &rect));
+
+    // Add a translucent text object to the new annotation.
+    FPDF_PAGEOBJECT text_object =
+        FPDFPageObj_NewTextObj(document(), "Arial", 12.0f);
+    EXPECT_TRUE(text_object);
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> text =
+        GetFPDFWideString(L"I'm a translucent text laying on other text.");
+    EXPECT_TRUE(FPDFText_SetText(text_object, text.get()));
+    EXPECT_TRUE(FPDFText_SetFillColor(text_object, 0, 0, 255, 150));
+    FPDFPageObj_Transform(text_object, 1, 0, 0, 1, 200, 600);
+    EXPECT_TRUE(FPDFAnnot_AppendObject(annot.get(), text_object));
+  }
+
+  // Check that the page renders correctly with the new text object.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_new_text);
+  }
+
+  {
+    // Retrieve the newly added stamp annotation and its text object.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(1, FPDFAnnot_GetObjectCount(annot.get()));
+    FPDF_PAGEOBJECT text_object = FPDFAnnot_GetObject(annot.get(), 0);
+    EXPECT_EQ(FPDF_PAGEOBJ_TEXT, FPDFPageObj_GetType(text_object));
+
+    // Modify the text in the new annotation.
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> new_text =
+        GetFPDFWideString(L"New text!");
+    EXPECT_TRUE(FPDFText_SetText(text_object, new_text.get()));
+    EXPECT_TRUE(FPDFAnnot_UpdateObject(annot.get(), text_object));
+  }
+
+  // Check that the page renders correctly with the modified text object.
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_modified_text);
+  }
+
+  // Remove the new annotation, and check that the page renders as before.
+  EXPECT_TRUE(FPDFPage_RemoveAnnot(page, 2));
+  {
+    std::unique_ptr<void, FPDFBitmapDeleter> bitmap =
+        RenderLoadedPageWithFlags(page, FPDF_ANNOT);
+    CompareBitmap(bitmap.get(), 595, 842, md5_original);
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetSetStringValue) {
+  // Open a file with four annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  static constexpr char kDateKey[] = "M";
+  static constexpr wchar_t kNewDate[] = L"D:201706282359Z00'00'";
+
+  {
+    // Retrieve the first annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that a non-existent key does not exist.
+    EXPECT_FALSE(FPDFAnnot_HasKey(annot.get(), "none"));
+
+    // Check that the string value of a non-string dictionary entry is empty.
+    static constexpr char kApKey[] = "AP";
+    EXPECT_TRUE(FPDFAnnot_HasKey(annot.get(), kApKey));
+    EXPECT_EQ(FPDF_OBJECT_REFERENCE,
+              FPDFAnnot_GetValueType(annot.get(), kApKey));
+    EXPECT_EQ(2u, FPDFAnnot_GetStringValue(annot.get(), kApKey, nullptr, 0));
+
+    // Check that the string value of the hash is correct.
+    static constexpr char kHashKey[] = "AAPL:Hash";
+    EXPECT_EQ(FPDF_OBJECT_NAME, FPDFAnnot_GetValueType(annot.get(), kHashKey));
+    unsigned long len =
+        FPDFAnnot_GetStringValue(annot.get(), kHashKey, nullptr, 0);
+    std::vector<char> buf(len);
+    EXPECT_EQ(66u,
+              FPDFAnnot_GetStringValue(annot.get(), kHashKey, buf.data(), len));
+    EXPECT_STREQ(L"395fbcb98d558681742f30683a62a2ad",
+                 BufferToWString(buf).c_str());
+
+    // Check that the string value of the modified date is correct.
+    EXPECT_EQ(FPDF_OBJECT_NAME, FPDFAnnot_GetValueType(annot.get(), kHashKey));
+    len = FPDFAnnot_GetStringValue(annot.get(), kDateKey, nullptr, 0);
+    buf.clear();
+    buf.resize(len);
+    EXPECT_EQ(44u,
+              FPDFAnnot_GetStringValue(annot.get(), kDateKey, buf.data(), len));
+    EXPECT_STREQ(L"D:201706071721Z00'00'", BufferToWString(buf).c_str());
+
+    // Update the date entry for the annotation.
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> text =
+        GetFPDFWideString(kNewDate);
+    EXPECT_TRUE(FPDFAnnot_SetStringValue(annot.get(), kDateKey, text.get()));
+  }
+
+  // Save the document, closing the page and document.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  UnloadPage(page);
+
+#if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
+  const char md5[] = "4d64e61c9c0f8c60ab3cc3234bb73b1c";
+#else
+  const char md5[] = "c96ee1f316d7f5a1b154de9f9d467f01";
+#endif
+
+  // Open the saved annotation.
+  OpenSavedDocument();
+  page = LoadSavedPage(0);
+  VerifySavedRendering(page, 595, 842, md5);
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> new_annot(
+        FPDFPage_GetAnnot(page, 0));
+
+    // Check that the string value of the modified date is the newly-set value.
+    EXPECT_EQ(FPDF_OBJECT_STRING,
+              FPDFAnnot_GetValueType(new_annot.get(), kDateKey));
+    unsigned long len =
+        FPDFAnnot_GetStringValue(new_annot.get(), kDateKey, nullptr, 0);
+    std::vector<char> buf(len);
+    EXPECT_EQ(44u, FPDFAnnot_GetStringValue(new_annot.get(), kDateKey,
+                                            buf.data(), len));
+    EXPECT_STREQ(kNewDate, BufferToWString(buf).c_str());
+  }
+
+  CloseSavedPage(page);
+  CloseSavedDocument();
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetSetAP) {
+  // Open a file with four annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve the first annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that the string value of an AP returns the expected length.
+    unsigned long normal_len = FPDFAnnot_GetAP(
+        annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL, nullptr, 0);
+    EXPECT_EQ(73970u, normal_len);
+
+    // Check that the string value of an AP is not returned if the buffer is too
+    // small. The result buffer should be overwritten with an empty string.
+    std::vector<char> buf(normal_len - 1);
+    // Write L"z" in the buffer to verify it's not overwritten.
+    wcscpy(reinterpret_cast<wchar_t*>(buf.data()), L"z");
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              buf.data(), buf.size()));
+    std::string ap = BufferToString(buf);
+    EXPECT_STREQ("z", ap.c_str());
+
+    // Check that the string value of an AP is returned through a buffer that is
+    // the right size.
+    buf.clear();
+    buf.resize(normal_len);
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              buf.data(), buf.size()));
+    ap = BufferToString(buf);
+    EXPECT_THAT(ap, testing::StartsWith("q Q q 7.442786 w 2 J"));
+    EXPECT_THAT(ap, testing::EndsWith("c 716.5381 327.7156 l S Q Q"));
+
+    // Check that the string value of an AP is returned through a buffer that is
+    // larger than necessary.
+    buf.clear();
+    buf.resize(normal_len + 1);
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              buf.data(), buf.size()));
+    ap = BufferToString(buf);
+    EXPECT_THAT(ap, testing::StartsWith("q Q q 7.442786 w 2 J"));
+    EXPECT_THAT(ap, testing::EndsWith("c 716.5381 327.7156 l S Q Q"));
+
+    // Check that getting an AP for a mode that does not have an AP returns an
+    // empty string.
+    unsigned long rollover_len = FPDFAnnot_GetAP(
+        annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER, nullptr, 0);
+    EXPECT_EQ(2u, rollover_len);
+
+    buf.clear();
+    buf.resize(1000);
+    EXPECT_EQ(2u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER,
+                              buf.data(), buf.size()));
+    EXPECT_STREQ("", BufferToString(buf).c_str());
+
+    // Check that setting the AP for an invalid appearance mode fails.
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> apText =
+        GetFPDFWideString(L"new test ap");
+    EXPECT_FALSE(FPDFAnnot_SetAP(annot.get(), -1, apText.get()));
+    EXPECT_FALSE(FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_COUNT,
+                                 apText.get()));
+    EXPECT_FALSE(FPDFAnnot_SetAP(
+        annot.get(), FPDF_ANNOT_APPEARANCEMODE_COUNT + 1, apText.get()));
+
+    // Set the AP correctly now.
+    EXPECT_TRUE(FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER,
+                                apText.get()));
+
+    // Check that the new annotation value is equal to the value we just set.
+    rollover_len = FPDFAnnot_GetAP(
+        annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER, nullptr, 0);
+    EXPECT_EQ(24u, rollover_len);
+    buf.clear();
+    buf.resize(rollover_len);
+    EXPECT_EQ(24u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER,
+                              buf.data(), buf.size()));
+    EXPECT_STREQ(L"new test ap", BufferToWString(buf).c_str());
+
+    // Check that the Normal AP was not touched when the Rollover AP was set.
+    buf.clear();
+    buf.resize(normal_len);
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              buf.data(), buf.size()));
+    ap = BufferToString(buf);
+    EXPECT_THAT(ap, testing::StartsWith("q Q q 7.442786 w 2 J"));
+    EXPECT_THAT(ap, testing::EndsWith("c 716.5381 327.7156 l S Q Q"));
+  }
+
+  // Save the modified document, then reopen it.
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  UnloadPage(page);
+
+  OpenSavedDocument();
+  page = LoadSavedPage(0);
+  {
+    std::unique_ptr<void, FPDFAnnotationDeleter> new_annot(
+        FPDFPage_GetAnnot(page, 0));
+
+    // Check that the new annotation value is equal to the value we set before
+    // saving.
+    unsigned long rollover_len = FPDFAnnot_GetAP(
+        new_annot.get(), FPDF_ANNOT_APPEARANCEMODE_ROLLOVER, nullptr, 0);
+    EXPECT_EQ(24u, rollover_len);
+    std::vector<char> buf(rollover_len);
+    EXPECT_EQ(24u, FPDFAnnot_GetAP(new_annot.get(),
+                                   FPDF_ANNOT_APPEARANCEMODE_ROLLOVER,
+                                   buf.data(), buf.size()));
+    EXPECT_STREQ(L"new test ap", BufferToWString(buf).c_str());
+  }
+
+  // Close saved document.
+  CloseSavedPage(page);
+  CloseSavedDocument();
+}
+
+TEST_F(FPDFAnnotEmbeddertest, RemoveOptionalAP) {
+  // Open a file with four annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve the first annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Set Down AP. Normal AP is already set.
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> apText =
+        GetFPDFWideString(L"new test ap");
+    EXPECT_TRUE(FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                apText.get()));
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              nullptr, 0));
+    EXPECT_EQ(24u, FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                   nullptr, 0));
+
+    // Check that setting the Down AP to null removes the Down entry but keeps
+    // Normal intact.
+    EXPECT_TRUE(
+        FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN, nullptr));
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              nullptr, 0));
+    EXPECT_EQ(2u, FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                  nullptr, 0));
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, RemoveRequiredAP) {
+  // Open a file with four annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_stamp_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve the first annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Set Down AP. Normal AP is already set.
+    std::unique_ptr<unsigned short, pdfium::FreeDeleter> apText =
+        GetFPDFWideString(L"new test ap");
+    EXPECT_TRUE(FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                apText.get()));
+    EXPECT_EQ(73970u,
+              FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                              nullptr, 0));
+    EXPECT_EQ(24u, FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                   nullptr, 0));
+
+    // Check that setting the Normal AP to null removes the whole AP dictionary.
+    EXPECT_TRUE(FPDFAnnot_SetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                                nullptr));
+    EXPECT_EQ(2u, FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_NORMAL,
+                                  nullptr, 0));
+    EXPECT_EQ(2u, FPDFAnnot_GetAP(annot.get(), FPDF_ANNOT_APPEARANCEMODE_DOWN,
+                                  nullptr, 0));
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, ExtractLinkedAnnotations) {
+  // Open a file with annotations and load its first page.
+  ASSERT_TRUE(OpenDocument("annotation_highlight_square_with_ap.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  EXPECT_EQ(-1, FPDFPage_GetAnnotIndex(page, nullptr));
+
+  {
+    // Retrieve the highlight annotation which has its popup defined.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+    EXPECT_EQ(FPDF_ANNOT_HIGHLIGHT, FPDFAnnot_GetSubtype(annot.get()));
+    EXPECT_EQ(0, FPDFPage_GetAnnotIndex(page, annot.get()));
+    static constexpr char kPopupKey[] = "Popup";
+    ASSERT_TRUE(FPDFAnnot_HasKey(annot.get(), kPopupKey));
+    ASSERT_EQ(FPDF_OBJECT_REFERENCE,
+              FPDFAnnot_GetValueType(annot.get(), kPopupKey));
+
+    // Retrieve and verify the popup of the highlight annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> popup(
+        FPDFAnnot_GetLinkedAnnot(annot.get(), kPopupKey));
+    ASSERT_TRUE(popup);
+    EXPECT_EQ(FPDF_ANNOT_POPUP, FPDFAnnot_GetSubtype(popup.get()));
+    EXPECT_EQ(1, FPDFPage_GetAnnotIndex(page, popup.get()));
+    FS_RECTF rect;
+    ASSERT_TRUE(FPDFAnnot_GetRect(popup.get(), &rect));
+    EXPECT_NEAR(612.0f, rect.left, 0.001f);
+    EXPECT_NEAR(578.792, rect.bottom, 0.001f);
+
+    // Attempting to retrieve |annot|'s "IRT"-linked annotation would fail,
+    // since "IRT" is not a key in |annot|'s dictionary.
+    static constexpr char kIRTKey[] = "IRT";
+    ASSERT_FALSE(FPDFAnnot_HasKey(annot.get(), kIRTKey));
+    EXPECT_FALSE(FPDFAnnot_GetLinkedAnnot(annot.get(), kIRTKey));
+
+    // Attempting to retrieve |annot|'s parent dictionary as an annotation
+    // would fail, since its parent is not an annotation.
+    static constexpr char kPKey[] = "P";
+    ASSERT_TRUE(FPDFAnnot_HasKey(annot.get(), kPKey));
+    EXPECT_EQ(FPDF_OBJECT_REFERENCE,
+              FPDFAnnot_GetValueType(annot.get(), kPKey));
+    EXPECT_FALSE(FPDFAnnot_GetLinkedAnnot(annot.get(), kPKey));
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetFormFieldFlagsTextField) {
+  // Open file with form text fields.
+  ASSERT_TRUE(OpenDocument("text_form_multiple.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve the first annotation: user-editable text field.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that the flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+  }
+
+  {
+    // Retrieve the second annotation: read-only text field.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 1));
+    ASSERT_TRUE(annot);
+
+    // Check that the flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_READONLY);
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetFormFieldFlagsComboBox) {
+  // Open file with form text fields.
+  ASSERT_TRUE(OpenDocument("combobox_form.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve the first annotation: user-editable combobox.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 0));
+    ASSERT_TRUE(annot);
+
+    // Check that the flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  {
+    // Retrieve the second annotation: regular combobox.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 1));
+    ASSERT_TRUE(annot);
+
+    // Check that the flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  {
+    // Retrieve the third annotation: read-only combobox.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFPage_GetAnnot(page, 2));
+    ASSERT_TRUE(annot);
+
+    // Check that the flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetFormAnnotNull) {
+  // Open file with form text fields.
+  EXPECT_TRUE(OpenDocument("text_form.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  // Attempt to get an annotation where no annotation exists on page.
+  FPDF_ANNOTATION annot =
+      FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 0, 0);
+  EXPECT_FALSE(annot);
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetFormAnnotAndCheckFlagsTextField) {
+  // Open file with form text fields.
+  EXPECT_TRUE(OpenDocument("text_form_multiple.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve user-editable text field annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 105, 118));
+    ASSERT_TRUE(annot);
+
+    // Check that interactive form annotation flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+  }
+
+  {
+    // Retrieve read-only text field annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 105, 202));
+    ASSERT_TRUE(annot);
+
+    // Check that interactive form annotation flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_READONLY);
+  }
+
+  UnloadPage(page);
+}
+
+TEST_F(FPDFAnnotEmbeddertest, GetFormAnnotAndCheckFlagsComboBox) {
+  // Open file with form comboboxes.
+  EXPECT_TRUE(OpenDocument("combobox_form.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+
+  {
+    // Retrieve user-editable combobox annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 102, 363));
+    ASSERT_TRUE(annot);
+
+    // Check that interactive form annotation flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  {
+    // Retrieve regular combobox annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 102, 413));
+    ASSERT_TRUE(annot);
+
+    // Check that interactive form annotation flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  {
+    // Retrieve read-only combobox annotation.
+    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
+        FPDFAnnot_GetFormFieldAtPoint(form_handle(), page, 102, 513));
+    ASSERT_TRUE(annot);
+
+    // Check that interactive form annotation flag values are as expected.
+    int flags = FPDFAnnot_GetFormFieldFlags(page, annot.get());
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_READONLY);
+    EXPECT_TRUE(flags & FPDF_FORMFLAG_CHOICE_COMBO);
+    EXPECT_FALSE(flags & FPDF_FORMFLAG_CHOICE_EDIT);
+  }
+
+  UnloadPage(page);
+}