Add embeddertest for CFWL_Edit

This CL adds two mouse selection tests for CFWL_Edit. In order to do so
the needed selection code was added to the XFA widget handler and
plumbed down to the CFWL_Edit field as needed.

Bug: pdfium:840
Change-Id: Ia3b5f5d191494a4579c01524df8fb35b24cc0085
Reviewed-on: https://pdfium-review.googlesource.com/14530
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

3 files changed, 88 insertions, 20 deletions

diff --git a/xfa/fwl/cfwl_edit.cpp b/xfa/fwl/cfwl_edit.cpp
index 426d46e761..d1f0c99a39 100644
--- a/xfa/fwl/cfwl_edit.cpp
+++ b/xfa/fwl/cfwl_edit.cpp
@@ -1120,7 +1120,7 @@ void CFWL_Edit::OnProcessMessage(CFWL_Message* pMessage) {
           OnMouseMove(pMsg);
           break;
         case FWL_MouseCommand::RightButtonDown:
-          DoButtonDown(pMsg);
+          DoRButtonDown(pMsg);
           break;
         default:
           break;
@@ -1159,17 +1159,11 @@ void CFWL_Edit::OnDrawWidget(CXFA_Graphics* pGraphics,
   DrawWidget(pGraphics, matrix);
 }
 
-void CFWL_Edit::DoButtonDown(CFWL_MessageMouse* pMsg) {
+void CFWL_Edit::DoRButtonDown(CFWL_MessageMouse* pMsg) {
   if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) == 0)
     SetFocus(true);
 
-  // TODO(dsinclair): Handle DoButtonDown
-  //  bool bBefore = true;
-  //  int32_t nIndex =
-  //      std::max(0, pPage->GetCharIndex(DeviceToEngine(pMsg->m_pos),
-  //      bBefore));
-
-  // SetCursorPosition(nIndex);
+  m_CursorPosition = m_EdtEngine.GetIndexForPoint(DeviceToEngine(pMsg->m_pos));
 }
 
 void CFWL_Edit::OnFocusChanged(CFWL_Message* pMsg, bool bSet) {
@@ -1206,7 +1200,9 @@ void CFWL_Edit::OnLButtonDown(CFWL_MessageMouse* pMsg) {
 
   m_bLButtonDown = true;
   SetGrab(true);
-  DoButtonDown(pMsg);
+
+  if ((m_pProperties->m_dwStates & FWL_WGTSTATE_Focused) == 0)
+    SetFocus(true);
 
   bool bRepaint = false;
   if (m_EdtEngine.HasSelection()) {
@@ -1216,13 +1212,16 @@ void CFWL_Edit::OnLButtonDown(CFWL_MessageMouse* pMsg) {
 
   size_t index_at_click =
       m_EdtEngine.GetIndexForPoint(DeviceToEngine(pMsg->m_pos));
+
   if (index_at_click != m_CursorPosition &&
       !!(pMsg->m_dwFlags & FWL_KEYFLAG_Shift)) {
     size_t start = std::min(m_CursorPosition, index_at_click);
     size_t end = std::max(m_CursorPosition, index_at_click);
 
-    m_EdtEngine.SetSelection(start, end);
+    m_EdtEngine.SetSelection(start, end - start);
     bRepaint = true;
+  } else {
+    m_CursorPosition = index_at_click;
   }
 
   if (bRepaint)
@@ -1259,14 +1258,16 @@ void CFWL_Edit::OnMouseMove(CFWL_MessageMouse* pMsg) {
   if (m_CursorPosition > length)
     SetCursorPosition(length);
 
-  size_t sel_start;
-  size_t count;
-  std::tie(sel_start, count) = m_EdtEngine.GetSelection();
-  size_t original_end = sel_start + count;
-  sel_start = std::min(sel_start, m_CursorPosition);
-  m_EdtEngine.SetSelection(
-      std::min(sel_start, m_CursorPosition),
-      std::max(original_end, m_CursorPosition) - sel_start);
+  size_t sel_start = 0;
+  size_t count = 0;
+  if (m_EdtEngine.HasSelection())
+    std::tie(sel_start, count) = m_EdtEngine.GetSelection();
+  else
+    sel_start = old_cursor_pos;
+
+  size_t start_pos = std::min(sel_start, m_CursorPosition);
+  size_t end_pos = std::max(sel_start, m_CursorPosition);
+  m_EdtEngine.SetSelection(start_pos, end_pos - start_pos);
 }
 
 void CFWL_Edit::OnKeyDown(CFWL_MessageKey* pMsg) {
diff --git a/xfa/fwl/cfwl_edit.h b/xfa/fwl/cfwl_edit.h
index cfebb25146..b7c252668b 100644
--- a/xfa/fwl/cfwl_edit.h
+++ b/xfa/fwl/cfwl_edit.h
@@ -142,7 +142,7 @@ class CFWL_Edit : public CFWL_Widget, public CFDE_TextEditEngine::Delegate {
   void SetCursorPosition(size_t position);
   void UpdateCursorRect();
 
-  void DoButtonDown(CFWL_MessageMouse* pMsg);
+  void DoRButtonDown(CFWL_MessageMouse* pMsg);
   void OnFocusChanged(CFWL_Message* pMsg, bool bSet);
   void OnLButtonDown(CFWL_MessageMouse* pMsg);
   void OnLButtonUp(CFWL_MessageMouse* pMsg);
diff --git a/xfa/fwl/cfwl_edit_embeddertest.cpp b/xfa/fwl/cfwl_edit_embeddertest.cpp
new file mode 100644
index 0000000000..c1575689eb
--- /dev/null
+++ b/xfa/fwl/cfwl_edit_embeddertest.cpp
@@ -0,0 +1,67 @@
+// 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 "core/fxcrt/widestring.h"
+#include "public/fpdf_formfill.h"
+#include "public/fpdf_fwlevent.h"
+#include "testing/embedder_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class CFWLEditEmbeddertest : public EmbedderTest {
+ protected:
+  void SetUp() override {
+    EmbedderTest::SetUp();
+    CreateAndInitializeFormPDF();
+  }
+
+  void TearDown() override {
+    UnloadPage(page());
+    EmbedderTest::TearDown();
+  }
+
+  void CreateAndInitializeFormPDF() {
+    EXPECT_TRUE(OpenDocument("xfa/email_recommended.pdf"));
+    page_ = LoadPage(0);
+    ASSERT_TRUE(page_);
+  }
+
+  FPDF_PAGE page() const { return page_; }
+
+ private:
+  FPDF_PAGE page_;
+};
+
+TEST_F(CFWLEditEmbeddertest, LeftClickMouseSelection) {
+  FORM_OnLButtonDown(form_handle(), page(), 0, 115, 58);
+  for (size_t i = 0; i < 10; ++i)
+    FORM_OnChar(form_handle(), page(), 'a' + i, 0);
+
+  // Mouse selection
+  FORM_OnLButtonDown(form_handle(), page(), 0, 128, 58);
+  FORM_OnLButtonDown(form_handle(), page(), FWL_EVENTFLAG_ShiftKey, 152, 58);
+
+  // 12 == (2 * strlen(defgh)) + 2 (for \0\0)
+  EXPECT_EQ(12UL, FORM_GetSelectedText(form_handle(), page(), nullptr, 0));
+
+  unsigned short buf[128];
+  unsigned long len = FORM_GetSelectedText(form_handle(), page(), &buf, 128);
+  EXPECT_STREQ(L"defgh", WideString::FromUTF16LE(buf, len).c_str());
+}
+
+TEST_F(CFWLEditEmbeddertest, DragMouseSelection) {
+  FORM_OnLButtonDown(form_handle(), page(), 0, 115, 58);
+  for (size_t i = 0; i < 10; ++i)
+    FORM_OnChar(form_handle(), page(), 'a' + i, 0);
+
+  // Mouse selection
+  FORM_OnLButtonDown(form_handle(), page(), 0, 128, 58);
+  FORM_OnMouseMove(form_handle(), page(), FWL_EVENTFLAG_ShiftKey, 152, 58);
+
+  // 12 == (2 * strlen(defgh)) + 2 (for \0\0)
+  EXPECT_EQ(12UL, FORM_GetSelectedText(form_handle(), page(), nullptr, 0));
+
+  unsigned short buf[128];
+  unsigned long len = FORM_GetSelectedText(form_handle(), page(), &buf, 128);
+  EXPECT_STREQ(L"defgh", WideString::FromUTF16LE(buf, len).c_str());
+}