[unseasoned-pdf] Set up the unit test framework for PdfViewWebPlugin.

Set up the unit test framework for PdfViewWebPlugin and add a test for
PdfViewWebPlugin::UpdateGeometry().

Bug: 1199558
Change-Id: I2f1fe0e5fa0ba727000bc642588b30dca9312052
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2847989
Reviewed-by: K. Moon <kmoon@chromium.org>
Commit-Queue: Hui Yingst <nigi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#877265}

pdf/BUILD.gn

@@ -381,6 +381,7 @@ if (enable_pdf) {
       "pdf_transform_unittest.cc",
       "pdf_utils/dates_unittest.cc",
       "pdf_view_plugin_base_unittest.cc",
+      "pdf_view_web_plugin_unittest.cc",
       "pdfium/accessibility_unittest.cc",
       "pdfium/findtext_unittest.cc",
       "pdfium/pdfium_engine_exports_unittest.cc",

pdf/pdf_view_web_plugin.cc

@@ -145,6 +145,11 @@ bool PdfViewWebPlugin::Initialize(blink::WebPluginContainer* container) {
   return InitializeCommon(std::make_unique<BlinkContainerWrapper>(container));
 }
 
+bool PdfViewWebPlugin::InitializeForTesting(
+    std::unique_ptr<ContainerWrapper> container_wrapper) {
+  return InitializeCommon(std::move(container_wrapper));
+}
+
 // Modeled on `OutOfProcessInstance::Init()`.
 bool PdfViewWebPlugin::InitializeCommon(
     std::unique_ptr<ContainerWrapper> container_wrapper) {

pdf/pdf_view_web_plugin.h

@@ -118,6 +118,12 @@ class PdfViewWebPlugin final : public PdfViewPluginBase,
   // SkiaGraphics::Client:
   void UpdateSnapshot(sk_sp<SkImage> snapshot) override;
 
+  // Initializes the plugin using the `container_wrapper` provided by tests.
+  bool InitializeForTesting(
+      std::unique_ptr<ContainerWrapper> container_wrapper);
+
+  const gfx::Rect& GetPluginRectForTesting() const { return plugin_rect(); }
+
  protected:
   // PdfViewPluginBase:
   base::WeakPtr<PdfViewPluginBase> GetWeakPtr() override;

pdf/pdf_view_web_plugin_unittest.cc

@@ -0,0 +1,109 @@
+// Copyright 2021 The Chromium 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 "pdf/pdf_view_web_plugin.h"
+
+#include <memory>
+#include <utility>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/blink/public/web/web_plugin_params.h"
+#include "ui/gfx/geometry/rect.h"
+
+namespace chrome_pdf {
+
+namespace {
+
+class FakeContainerWrapper final : public PdfViewWebPlugin::ContainerWrapper {
+ public:
+  FakeContainerWrapper() = default;
+  FakeContainerWrapper(const FakeContainerWrapper&) = delete;
+  FakeContainerWrapper& operator=(const FakeContainerWrapper&) = delete;
+  ~FakeContainerWrapper() override = default;
+
+  // PdfViewWebPlugin::ContainerWrapper:
+  void Invalidate() override {}
+
+  float DeviceScaleFactor() const override { return device_scale_; }
+
+  blink::WebPluginContainer* Container() override { return nullptr; }
+
+  void set_device_scale(float device_scale) { device_scale_ = device_scale; }
+
+ private:
+  float device_scale_ = 1.0f;
+};
+
+}  // namespace
+
+class PdfViewWebPluginTest : public testing::Test {
+ public:
+  // Custom deleter for `plugin_`. PdfViewWebPlugin must be destroyed by
+  // PdfViewWebPlugin::Destroy() instead of its destructor.
+  struct PluginDeleter {
+    void operator()(PdfViewWebPlugin* ptr) { ptr->Destroy(); }
+  };
+
+  PdfViewWebPluginTest() = default;
+  PdfViewWebPluginTest(const PdfViewWebPluginTest&) = delete;
+  PdfViewWebPluginTest& operator=(const PdfViewWebPluginTest&) = delete;
+  ~PdfViewWebPluginTest() override = default;
+
+  void SetUp() override {
+    plugin_ = std::unique_ptr<PdfViewWebPlugin, PluginDeleter>(
+        new PdfViewWebPlugin(blink::WebPluginParams()));
+
+    auto wrapper = std::make_unique<FakeContainerWrapper>();
+    wrapper_ptr_ = wrapper.get();
+    plugin_->InitializeForTesting(std::move(wrapper));
+  }
+
+  void TearDown() override {
+    plugin_.reset();
+    wrapper_ptr_ = nullptr;
+  }
+
+  void TestUpdateGeometrySetsPluginRect(float device_scale,
+                                        const gfx::Rect& window_rect,
+                                        const gfx::Rect& expected_plugin_rect) {
+    // The plugin container's device scale must be set before calling
+    // UpdateGeometry().
+    ASSERT_TRUE(wrapper_ptr_);
+    wrapper_ptr_->set_device_scale(device_scale);
+    plugin_->UpdateGeometry(window_rect, window_rect, window_rect,
+                            /*is_visible=*/true);
+
+    EXPECT_EQ(expected_plugin_rect, plugin_->GetPluginRectForTesting())
+        << "Failure at device scale of " << device_scale << ", window rect of "
+        << window_rect.ToString();
+  }
+
+  FakeContainerWrapper* wrapper_ptr_;
+  std::unique_ptr<PdfViewWebPlugin, PluginDeleter> plugin_;
+};
+
+TEST_F(PdfViewWebPluginTest, UpdateGeometrySetsPluginRect) {
+  struct UpdateGeometryParams {
+    // The plugin container's device scale.
+    float device_scale;
+
+    //  The window area.
+    gfx::Rect window_rect;
+
+    // The expected plugin rect.
+    gfx::Rect expected_plugin_rect;
+  };
+
+  static constexpr UpdateGeometryParams kUpdateGeometryParams[] = {
+      {1.0f, gfx::Rect(3, 4, 5, 6), gfx::Rect(3, 4, 5, 6)},
+      {2.0f, gfx::Rect(5, 6, 7, 8), gfx::Rect(10, 12, 14, 16)},
+  };
+
+  for (const auto& params : kUpdateGeometryParams) {
+    TestUpdateGeometrySetsPluginRect(params.device_scale, params.window_rect,
+                                     params.expected_plugin_rect);
+  }
+}
+
+}  // namespace chrome_pdf