Replace CLines class with std::vector<Cline>.

m_LineArray only grows via push_back of non-null pointer, so
remove some null checks.

Another little idiosyncrasy is CLines::Clear() doesn't clear the
items in CLines, only the things that were once in CLines but aren't
anymore.  So don't call it.

Change-Id: Icc434be94b1b0522533c7533b8f6b2736bb864c4
Reviewed-on: https://pdfium-review.googlesource.com/3099
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

8 files changed, 310 insertions, 386 deletions

diff --git a/core/fpdfdoc/cline.cpp b/core/fpdfdoc/cline.cpp
index 2e8477cfe7..a24b81950a 100644
--- a/core/fpdfdoc/cline.cpp
+++ b/core/fpdfdoc/cline.cpp
@@ -8,6 +8,8 @@
 
 CLine::CLine() {}
 
+CLine::CLine(const CPVT_LineInfo& lineinfo) : m_LineInfo(lineinfo) {}
+
 CLine::~CLine() {}
 
 CPVT_WordPlace CLine::GetBeginWordPlace() const {
diff --git a/core/fpdfdoc/cline.h b/core/fpdfdoc/cline.h
index 6f95beb546..67bf06b649 100644
--- a/core/fpdfdoc/cline.h
+++ b/core/fpdfdoc/cline.h
@@ -10,9 +10,10 @@
 #include "core/fpdfdoc/cpvt_lineinfo.h"
 #include "core/fpdfdoc/cpvt_wordplace.h"
 
-class CLine final {
+class CLine {
  public:
   CLine();
+  explicit CLine(const CPVT_LineInfo& lineinfo);
   ~CLine();
 
   CPVT_WordPlace GetBeginWordPlace() const;
diff --git a/core/fpdfdoc/clines.cpp b/core/fpdfdoc/clines.cpp
deleted file mode 100644
index 1e425eab93..0000000000
--- a/core/fpdfdoc/clines.cpp
+++ /dev/null
@@ -1,52 +0,0 @@
-// 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.
-
-// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-
-#include "core/fpdfdoc/clines.h"
-
-#include "core/fpdfdoc/cline.h"
-
-CLines::CLines() : m_nTotal(0) {}
-
-CLines::~CLines() {
-  RemoveAll();
-}
-
-int32_t CLines::GetSize() const {
-  return m_Lines.GetSize();
-}
-
-CLine* CLines::GetAt(int32_t nIndex) const {
-  return m_Lines.GetAt(nIndex);
-}
-
-void CLines::Empty() {
-  m_nTotal = 0;
-}
-
-void CLines::RemoveAll() {
-  for (int32_t i = 0, sz = GetSize(); i < sz; i++)
-    delete GetAt(i);
-  m_Lines.RemoveAll();
-  m_nTotal = 0;
-}
-
-int32_t CLines::Add(const CPVT_LineInfo& lineinfo) {
-  if (m_nTotal >= GetSize()) {
-    CLine* pLine = new CLine;
-    pLine->m_LineInfo = lineinfo;
-    m_Lines.Add(pLine);
-  } else if (CLine* pLine = GetAt(m_nTotal)) {
-    pLine->m_LineInfo = lineinfo;
-  }
-  return m_nTotal++;
-}
-
-void CLines::Clear() {
-  for (int32_t i = GetSize() - 1; i >= m_nTotal; i--) {
-    delete GetAt(i);
-    m_Lines.RemoveAt(i);
-  }
-}
diff --git a/core/fpdfdoc/clines.h b/core/fpdfdoc/clines.h
deleted file mode 100644
index b4db0e3966..0000000000
--- a/core/fpdfdoc/clines.h
+++ /dev/null
@@ -1,35 +0,0 @@
-// 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.
-
-// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-
-#ifndef CORE_FPDFDOC_CLINES_H_
-#define CORE_FPDFDOC_CLINES_H_
-
-#include <stdint.h>
-
-#include "core/fpdfdoc/cpvt_arraytemplate.h"
-#include "core/fpdfdoc/cpvt_lineinfo.h"
-
-class CLine;
-
-class CLines final {
- public:
-  CLines();
-  ~CLines();
-
-  int32_t GetSize() const;
-  CLine* GetAt(int32_t nIndex) const;
-
-  void Empty();
-  void RemoveAll();
-  int32_t Add(const CPVT_LineInfo& lineinfo);
-  void Clear();
-
- private:
-  CPVT_ArrayTemplate<CLine*> m_Lines;
-  int32_t m_nTotal;
-};
-
-#endif  // CORE_FPDFDOC_CLINES_H_
diff --git a/core/fpdfdoc/cpdf_variabletext.cpp b/core/fpdfdoc/cpdf_variabletext.cpp
index 5dabf8db0c..d5333192f5 100644
--- a/core/fpdfdoc/cpdf_variabletext.cpp
+++ b/core/fpdfdoc/cpdf_variabletext.cpp
@@ -16,6 +16,7 @@
 #include "core/fpdfdoc/csection.h"
 #include "core/fpdfdoc/ipvt_fontmap.h"
 #include "third_party/base/ptr_util.h"
+#include "third_party/base/stl_util.h"
 
 namespace {
 
@@ -112,37 +113,41 @@ bool CPDF_VariableText::Iterator::PrevWord() {
 }
 
 bool CPDF_VariableText::Iterator::NextLine() {
-  if (CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (m_CurPos.nLineIndex < pSection->m_LineArray.GetSize() - 1) {
-      m_CurPos =
-          CPVT_WordPlace(m_CurPos.nSecIndex, m_CurPos.nLineIndex + 1, -1);
-      return true;
-    }
-    if (m_CurPos.nSecIndex < m_pVT->m_SectionArray.GetSize() - 1) {
-      m_CurPos = CPVT_WordPlace(m_CurPos.nSecIndex + 1, 0, -1);
-      return true;
-    }
+  CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex);
+  if (!pSection)
+    return false;
+
+  if (m_CurPos.nLineIndex <
+      pdfium::CollectionSize<int32_t>(pSection->m_LineArray) - 1) {
+    m_CurPos = CPVT_WordPlace(m_CurPos.nSecIndex, m_CurPos.nLineIndex + 1, -1);
+    return true;
+  }
+  if (m_CurPos.nSecIndex < m_pVT->m_SectionArray.GetSize() - 1) {
+    m_CurPos = CPVT_WordPlace(m_CurPos.nSecIndex + 1, 0, -1);
+    return true;
   }
   return false;
 }
 
 bool CPDF_VariableText::Iterator::PrevLine() {
-  if (m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (m_CurPos.nLineIndex > 0) {
-      m_CurPos =
-          CPVT_WordPlace(m_CurPos.nSecIndex, m_CurPos.nLineIndex - 1, -1);
-      return true;
-    }
-    if (m_CurPos.nSecIndex > 0) {
-      if (CSection* pLastSection =
-              m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex - 1)) {
-        m_CurPos = CPVT_WordPlace(m_CurPos.nSecIndex - 1,
-                                  pLastSection->m_LineArray.GetSize() - 1, -1);
-        return true;
-      }
-    }
+  if (!m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex))
+    return false;
+
+  if (m_CurPos.nLineIndex > 0) {
+    m_CurPos = CPVT_WordPlace(m_CurPos.nSecIndex, m_CurPos.nLineIndex - 1, -1);
+    return true;
   }
-  return false;
+  if (m_CurPos.nSecIndex <= 0)
+    return false;
+
+  CSection* pLastSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex - 1);
+  if (!pLastSection)
+    return false;
+
+  m_CurPos = CPVT_WordPlace(
+      m_CurPos.nSecIndex - 1,
+      pdfium::CollectionSize<int32_t>(pLastSection->m_LineArray) - 1, -1);
+  return true;
 }
 
 bool CPDF_VariableText::Iterator::NextSection() {
@@ -164,58 +169,65 @@ bool CPDF_VariableText::Iterator::PrevSection() {
 
 bool CPDF_VariableText::Iterator::GetWord(CPVT_Word& word) const {
   word.WordPlace = m_CurPos;
-  if (CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (pSection->m_LineArray.GetAt(m_CurPos.nLineIndex)) {
-      if (CPVT_WordInfo* pWord =
-              pSection->m_WordArray.GetAt(m_CurPos.nWordIndex)) {
-        word.Word = pWord->Word;
-        word.nCharset = pWord->nCharset;
-        word.fWidth = m_pVT->GetWordWidth(*pWord);
-        word.ptWord = m_pVT->InToOut(
-            CFX_PointF(pWord->fWordX + pSection->m_SecInfo.rcSection.left,
-                       pWord->fWordY + pSection->m_SecInfo.rcSection.top));
-        word.fAscent = m_pVT->GetWordAscent(*pWord);
-        word.fDescent = m_pVT->GetWordDescent(*pWord);
-        if (pWord->pWordProps)
-          word.WordProps = *pWord->pWordProps;
-
-        word.nFontIndex = m_pVT->GetWordFontIndex(*pWord);
-        word.fFontSize = m_pVT->GetWordFontSize(*pWord);
-        return true;
-      }
-    }
-  }
-  return false;
+  CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex);
+  if (!pSection)
+    return false;
+
+  if (!pdfium::IndexInBounds(pSection->m_LineArray, m_CurPos.nLineIndex))
+    return false;
+
+  CPVT_WordInfo* pWord = pSection->m_WordArray.GetAt(m_CurPos.nWordIndex);
+  if (!pWord)
+    return false;
+
+  word.Word = pWord->Word;
+  word.nCharset = pWord->nCharset;
+  word.fWidth = m_pVT->GetWordWidth(*pWord);
+  word.ptWord = m_pVT->InToOut(
+      CFX_PointF(pWord->fWordX + pSection->m_SecInfo.rcSection.left,
+                 pWord->fWordY + pSection->m_SecInfo.rcSection.top));
+  word.fAscent = m_pVT->GetWordAscent(*pWord);
+  word.fDescent = m_pVT->GetWordDescent(*pWord);
+  if (pWord->pWordProps)
+    word.WordProps = *pWord->pWordProps;
+  word.nFontIndex = m_pVT->GetWordFontIndex(*pWord);
+  word.fFontSize = m_pVT->GetWordFontSize(*pWord);
+  return true;
 }
 
 bool CPDF_VariableText::Iterator::SetWord(const CPVT_Word& word) {
-  if (CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (CPVT_WordInfo* pWord =
-            pSection->m_WordArray.GetAt(m_CurPos.nWordIndex)) {
-      if (pWord->pWordProps)
-        *pWord->pWordProps = word.WordProps;
-      return true;
-    }
-  }
-  return false;
+  CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex);
+  if (!pSection)
+    return false;
+
+  CPVT_WordInfo* pWord = pSection->m_WordArray.GetAt(m_CurPos.nWordIndex);
+  if (!pWord)
+    return false;
+
+  if (pWord->pWordProps)
+    *pWord->pWordProps = word.WordProps;
+  return true;
 }
 
 bool CPDF_VariableText::Iterator::GetLine(CPVT_Line& line) const {
   ASSERT(m_pVT);
   line.lineplace = CPVT_WordPlace(m_CurPos.nSecIndex, m_CurPos.nLineIndex, -1);
-  if (CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (CLine* pLine = pSection->m_LineArray.GetAt(m_CurPos.nLineIndex)) {
-      line.ptLine = m_pVT->InToOut(CFX_PointF(
-          pLine->m_LineInfo.fLineX + pSection->m_SecInfo.rcSection.left,
-          pLine->m_LineInfo.fLineY + pSection->m_SecInfo.rcSection.top));
-      line.fLineWidth = pLine->m_LineInfo.fLineWidth;
-      line.fLineAscent = pLine->m_LineInfo.fLineAscent;
-      line.fLineDescent = pLine->m_LineInfo.fLineDescent;
-      line.lineEnd = pLine->GetEndWordPlace();
-      return true;
-    }
-  }
-  return false;
+  CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex);
+  if (!pSection)
+    return false;
+
+  if (!pdfium::IndexInBounds(pSection->m_LineArray, m_CurPos.nLineIndex))
+    return false;
+
+  CLine* pLine = pSection->m_LineArray[m_CurPos.nLineIndex].get();
+  line.ptLine = m_pVT->InToOut(
+      CFX_PointF(pLine->m_LineInfo.fLineX + pSection->m_SecInfo.rcSection.left,
+                 pLine->m_LineInfo.fLineY + pSection->m_SecInfo.rcSection.top));
+  line.fLineWidth = pLine->m_LineInfo.fLineWidth;
+  line.fLineAscent = pLine->m_LineInfo.fLineAscent;
+  line.fLineDescent = pLine->m_LineInfo.fLineDescent;
+  line.lineEnd = pLine->GetEndWordPlace();
+  return true;
 }
 
 bool CPDF_VariableText::Iterator::GetSection(CPVT_Section& section) const {
@@ -232,14 +244,15 @@ bool CPDF_VariableText::Iterator::GetSection(CPVT_Section& section) const {
 }
 
 bool CPDF_VariableText::Iterator::SetSection(const CPVT_Section& section) {
-  if (CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex)) {
-    if (pSection->m_SecInfo.pSecProps)
-      *pSection->m_SecInfo.pSecProps = section.SecProps;
-    if (pSection->m_SecInfo.pWordProps)
-      *pSection->m_SecInfo.pWordProps = section.WordProps;
-    return true;
-  }
-  return false;
+  CSection* pSection = m_pVT->m_SectionArray.GetAt(m_CurPos.nSecIndex);
+  if (!pSection)
+    return false;
+
+  if (pSection->m_SecInfo.pSecProps)
+    *pSection->m_SecInfo.pSecProps = section.SecProps;
+  if (pSection->m_SecInfo.pWordProps)
+    *pSection->m_SecInfo.pWordProps = section.WordProps;
+  return true;
 }
 
 CPDF_VariableText::CPDF_VariableText()
@@ -602,7 +615,8 @@ CPVT_WordPlace CPDF_VariableText::GetUpWordPlace(
     }
     if (temp.nSecIndex-- > 0) {
       if (CSection* pLastSection = m_SectionArray.GetAt(temp.nSecIndex)) {
-        temp.nLineIndex = pLastSection->m_LineArray.GetSize() - 1;
+        temp.nLineIndex =
+            pdfium::CollectionSize<int32_t>(pLastSection->m_LineArray) - 1;
         return pLastSection->SearchWordPlace(
             pt.x - pLastSection->m_SecInfo.rcSection.left, temp);
       }
@@ -617,7 +631,8 @@ CPVT_WordPlace CPDF_VariableText::GetDownWordPlace(
   if (CSection* pSection = m_SectionArray.GetAt(place.nSecIndex)) {
     CPVT_WordPlace temp = place;
     CFX_PointF pt = OutToIn(point);
-    if (temp.nLineIndex++ < pSection->m_LineArray.GetSize() - 1) {
+    if (temp.nLineIndex++ <
+        pdfium::CollectionSize<int32_t>(pSection->m_LineArray) - 1) {
       return pSection->SearchWordPlace(
           pt.x - pSection->m_SecInfo.rcSection.left, temp);
     }
@@ -639,11 +654,14 @@ CPVT_WordPlace CPDF_VariableText::GetLineBeginPlace(
 
 CPVT_WordPlace CPDF_VariableText::GetLineEndPlace(
     const CPVT_WordPlace& place) const {
-  if (CSection* pSection = m_SectionArray.GetAt(place.nSecIndex)) {
-    if (CLine* pLine = pSection->m_LineArray.GetAt(place.nLineIndex))
-      return pLine->GetEndWordPlace();
-  }
-  return place;
+  CSection* pSection = m_SectionArray.GetAt(place.nSecIndex);
+  if (!pSection)
+    return place;
+
+  if (!pdfium::IndexInBounds(pSection->m_LineArray, place.nLineIndex))
+    return place;
+
+  return pSection->m_LineArray[place.nLineIndex]->GetEndWordPlace();
 }
 
 CPVT_WordPlace CPDF_VariableText::GetSectionBeginPlace(
@@ -739,13 +757,15 @@ bool CPDF_VariableText::SetWordInfo(const CPVT_WordPlace& place,
 
 bool CPDF_VariableText::GetLineInfo(const CPVT_WordPlace& place,
                                     CPVT_LineInfo& lineinfo) {
-  if (CSection* pSection = m_SectionArray.GetAt(place.nSecIndex)) {
-    if (CLine* pLine = pSection->m_LineArray.GetAt(place.nLineIndex)) {
-      lineinfo = pLine->m_LineInfo;
-      return true;
-    }
-  }
-  return false;
+  CSection* pSection = m_SectionArray.GetAt(place.nSecIndex);
+  if (!pSection)
+    return false;
+
+  if (!pdfium::IndexInBounds(pSection->m_LineArray, place.nLineIndex))
+    return false;
+
+  lineinfo = pSection->m_LineArray[place.nLineIndex]->m_LineInfo;
+  return true;
 }
 
 bool CPDF_VariableText::GetSectionInfo(const CPVT_WordPlace& place,
diff --git a/core/fpdfdoc/csection.cpp b/core/fpdfdoc/csection.cpp
index ce78418dc5..981f6d0b54 100644
--- a/core/fpdfdoc/csection.cpp
+++ b/core/fpdfdoc/csection.cpp
@@ -10,6 +10,8 @@
 
 #include "core/fpdfdoc/cline.h"
 #include "core/fpdfdoc/cpvt_wordinfo.h"
+#include "third_party/base/ptr_util.h"
+#include "third_party/base/stl_util.h"
 
 CSection::CSection(CPDF_VariableText* pVT) : m_pVT(pVT) {}
 
@@ -23,7 +25,7 @@ void CSection::ResetAll() {
 }
 
 void CSection::ResetLineArray() {
-  m_LineArray.RemoveAll();
+  m_LineArray.clear();
 }
 
 void CSection::ResetWordArray() {
@@ -34,10 +36,10 @@ void CSection::ResetWordArray() {
 }
 
 void CSection::ResetLinePlace() {
-  for (int32_t i = 0, sz = m_LineArray.GetSize(); i < sz; i++) {
-    if (CLine* pLine = m_LineArray.GetAt(i)) {
-      pLine->LinePlace = CPVT_WordPlace(SecPlace.nSecIndex, i, -1);
-    }
+  int32_t i = 0;
+  for (auto& pLine : m_LineArray) {
+    pLine->LinePlace = CPVT_WordPlace(SecPlace.nSecIndex, i, -1);
+    ++i;
   }
 }
 
@@ -55,7 +57,8 @@ CPVT_WordPlace CSection::AddWord(const CPVT_WordPlace& place,
 }
 
 CPVT_WordPlace CSection::AddLine(const CPVT_LineInfo& lineinfo) {
-  return CPVT_WordPlace(SecPlace.nSecIndex, m_LineArray.Add(lineinfo), -1);
+  m_LineArray.push_back(pdfium::MakeUnique<CLine>(lineinfo));
+  return CPVT_WordPlace(SecPlace.nSecIndex, m_LineArray.size() - 1, -1);
 }
 
 CPVT_FloatRect CSection::Rearrange() {
@@ -70,78 +73,69 @@ CFX_SizeF CSection::GetSectionSize(float fFontSize) {
 }
 
 CPVT_WordPlace CSection::GetBeginWordPlace() const {
-  if (CLine* pLine = m_LineArray.GetAt(0)) {
-    return pLine->GetBeginWordPlace();
-  }
-  return SecPlace;
+  if (m_LineArray.empty())
+    return SecPlace;
+  return m_LineArray.front()->GetBeginWordPlace();
 }
 
 CPVT_WordPlace CSection::GetEndWordPlace() const {
-  if (CLine* pLine = m_LineArray.GetAt(m_LineArray.GetSize() - 1)) {
-    return pLine->GetEndWordPlace();
-  }
-  return SecPlace;
+  if (m_LineArray.empty())
+    return SecPlace;
+  return m_LineArray.back()->GetEndWordPlace();
 }
 
 CPVT_WordPlace CSection::GetPrevWordPlace(const CPVT_WordPlace& place) const {
-  if (place.nLineIndex < 0) {
+  if (place.nLineIndex < 0)
     return GetBeginWordPlace();
-  }
-  if (place.nLineIndex >= m_LineArray.GetSize()) {
+
+  if (place.nLineIndex >= pdfium::CollectionSize<int32_t>(m_LineArray))
     return GetEndWordPlace();
-  }
-  if (CLine* pLine = m_LineArray.GetAt(place.nLineIndex)) {
-    if (place.nWordIndex == pLine->m_LineInfo.nBeginWordIndex) {
-      return CPVT_WordPlace(place.nSecIndex, place.nLineIndex, -1);
-    }
-    if (place.nWordIndex < pLine->m_LineInfo.nBeginWordIndex) {
-      if (CLine* pPrevLine = m_LineArray.GetAt(place.nLineIndex - 1)) {
-        return pPrevLine->GetEndWordPlace();
-      }
-    } else {
-      return pLine->GetPrevWordPlace(place);
-    }
-  }
-  return place;
+
+  CLine* pLine = m_LineArray[place.nLineIndex].get();
+  if (place.nWordIndex == pLine->m_LineInfo.nBeginWordIndex)
+    return CPVT_WordPlace(place.nSecIndex, place.nLineIndex, -1);
+
+  if (place.nWordIndex >= pLine->m_LineInfo.nBeginWordIndex)
+    return pLine->GetPrevWordPlace(place);
+
+  if (!pdfium::IndexInBounds(m_LineArray, place.nLineIndex - 1))
+    return place;
+
+  return m_LineArray[place.nLineIndex - 1]->GetEndWordPlace();
 }
 
 CPVT_WordPlace CSection::GetNextWordPlace(const CPVT_WordPlace& place) const {
-  if (place.nLineIndex < 0) {
+  if (place.nLineIndex < 0)
     return GetBeginWordPlace();
-  }
-  if (place.nLineIndex >= m_LineArray.GetSize()) {
+
+  if (place.nLineIndex >= pdfium::CollectionSize<int32_t>(m_LineArray))
     return GetEndWordPlace();
-  }
-  if (CLine* pLine = m_LineArray.GetAt(place.nLineIndex)) {
-    if (place.nWordIndex >= pLine->m_LineInfo.nEndWordIndex) {
-      if (CLine* pNextLine = m_LineArray.GetAt(place.nLineIndex + 1)) {
-        return pNextLine->GetBeginWordPlace();
-      }
-    } else {
-      return pLine->GetNextWordPlace(place);
-    }
-  }
-  return place;
+
+  CLine* pLine = m_LineArray[place.nLineIndex].get();
+  if (place.nWordIndex < pLine->m_LineInfo.nEndWordIndex)
+    return pLine->GetNextWordPlace(place);
+
+  if (!pdfium::IndexInBounds(m_LineArray, place.nLineIndex + 1))
+    return place;
+
+  return m_LineArray[place.nLineIndex + 1]->GetBeginWordPlace();
 }
 
 void CSection::UpdateWordPlace(CPVT_WordPlace& place) const {
   int32_t nLeft = 0;
-  int32_t nRight = m_LineArray.GetSize() - 1;
+  int32_t nRight = pdfium::CollectionSize<int32_t>(m_LineArray) - 1;
   int32_t nMid = (nLeft + nRight) / 2;
   while (nLeft <= nRight) {
-    if (CLine* pLine = m_LineArray.GetAt(nMid)) {
-      if (place.nWordIndex < pLine->m_LineInfo.nBeginWordIndex) {
-        nRight = nMid - 1;
-        nMid = (nLeft + nRight) / 2;
-      } else if (place.nWordIndex > pLine->m_LineInfo.nEndWordIndex) {
-        nLeft = nMid + 1;
-        nMid = (nLeft + nRight) / 2;
-      } else {
-        place.nLineIndex = nMid;
-        return;
-      }
+    CLine* pLine = m_LineArray[nMid].get();
+    if (place.nWordIndex < pLine->m_LineInfo.nBeginWordIndex) {
+      nRight = nMid - 1;
+      nMid = (nLeft + nRight) / 2;
+    } else if (place.nWordIndex > pLine->m_LineInfo.nEndWordIndex) {
+      nLeft = nMid + 1;
+      nMid = (nLeft + nRight) / 2;
     } else {
-      break;
+      place.nLineIndex = nMid;
+      return;
     }
   }
 }
@@ -152,58 +146,52 @@ CPVT_WordPlace CSection::SearchWordPlace(const CFX_PointF& point) const {
   bool bUp = true;
   bool bDown = true;
   int32_t nLeft = 0;
-  int32_t nRight = m_LineArray.GetSize() - 1;
-  int32_t nMid = m_LineArray.GetSize() / 2;
-  float fTop = 0;
-  float fBottom = 0;
+  int32_t nRight = pdfium::CollectionSize<int32_t>(m_LineArray) - 1;
+  int32_t nMid = pdfium::CollectionSize<int32_t>(m_LineArray) / 2;
   while (nLeft <= nRight) {
-    if (CLine* pLine = m_LineArray.GetAt(nMid)) {
-      fTop = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineAscent -
-             m_pVT->GetLineLeading(m_SecInfo);
-      fBottom = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineDescent;
-      if (IsFloatBigger(point.y, fTop)) {
-        bUp = false;
-      }
-      if (IsFloatSmaller(point.y, fBottom)) {
-        bDown = false;
-      }
-      if (IsFloatSmaller(point.y, fTop)) {
-        nRight = nMid - 1;
-        nMid = (nLeft + nRight) / 2;
-        continue;
-      } else if (IsFloatBigger(point.y, fBottom)) {
-        nLeft = nMid + 1;
-        nMid = (nLeft + nRight) / 2;
-        continue;
-      } else {
-        place = SearchWordPlace(
-            point.x,
-            CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
-                           pLine->GetEndWordPlace()));
-        place.nLineIndex = nMid;
-        return place;
-      }
+    CLine* pLine = m_LineArray[nMid].get();
+    float fTop = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineAscent -
+                 m_pVT->GetLineLeading(m_SecInfo);
+    float fBottom = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineDescent;
+    if (IsFloatBigger(point.y, fTop))
+      bUp = false;
+    if (IsFloatSmaller(point.y, fBottom))
+      bDown = false;
+    if (IsFloatSmaller(point.y, fTop)) {
+      nRight = nMid - 1;
+      nMid = (nLeft + nRight) / 2;
+      continue;
+    }
+    if (IsFloatBigger(point.y, fBottom)) {
+      nLeft = nMid + 1;
+      nMid = (nLeft + nRight) / 2;
+      continue;
     }
+    place = SearchWordPlace(
+        point.x,
+        CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
+                       pLine->GetEndWordPlace()));
+    place.nLineIndex = nMid;
+    return place;
   }
-  if (bUp) {
+  if (bUp)
     place = GetBeginWordPlace();
-  }
-  if (bDown) {
+  if (bDown)
     place = GetEndWordPlace();
-  }
   return place;
 }
 
 CPVT_WordPlace CSection::SearchWordPlace(
     float fx,
     const CPVT_WordPlace& lineplace) const {
-  if (CLine* pLine = m_LineArray.GetAt(lineplace.nLineIndex)) {
-    return SearchWordPlace(
-        fx - m_SecInfo.rcSection.left,
-        CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
-                       pLine->GetEndWordPlace()));
-  }
-  return GetBeginWordPlace();
+  if (!pdfium::IndexInBounds(m_LineArray, lineplace.nLineIndex))
+    return GetBeginWordPlace();
+
+  CLine* pLine = m_LineArray[lineplace.nLineIndex].get();
+  return SearchWordPlace(
+      fx - m_SecInfo.rcSection.left,
+      CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
+                     pLine->GetEndWordPlace()));
 }
 
 CPVT_WordPlace CSection::SearchWordPlace(float fx,
diff --git a/core/fpdfdoc/csection.h b/core/fpdfdoc/csection.h
index b82409dc6f..6907b3dc45 100644
--- a/core/fpdfdoc/csection.h
+++ b/core/fpdfdoc/csection.h
@@ -7,7 +7,10 @@
 #ifndef CORE_FPDFDOC_CSECTION_H_
 #define CORE_FPDFDOC_CSECTION_H_
 
-#include "core/fpdfdoc/clines.h"
+#include <memory>
+#include <vector>
+
+#include "core/fpdfdoc/cline.h"
 #include "core/fpdfdoc/cpvt_sectioninfo.h"
 #include "core/fpdfdoc/ctypeset.h"
 #include "core/fxcrt/fx_coordinates.h"
@@ -46,7 +49,7 @@ class CSection final {
 
   CPVT_WordPlace SecPlace;
   CPVT_SectionInfo m_SecInfo;
-  CLines m_LineArray;
+  std::vector<std::unique_ptr<CLine>> m_LineArray;
   CPVT_ArrayTemplate<CPVT_WordInfo*> m_WordArray;
 
  private:
diff --git a/core/fpdfdoc/ctypeset.cpp b/core/fpdfdoc/ctypeset.cpp
index 6cfaff5cc8..34deb216b2 100644
--- a/core/fpdfdoc/ctypeset.cpp
+++ b/core/fpdfdoc/ctypeset.cpp
@@ -11,6 +11,7 @@
 #include "core/fpdfdoc/cline.h"
 #include "core/fpdfdoc/cpvt_wordinfo.h"
 #include "core/fpdfdoc/csection.h"
+#include "third_party/base/stl_util.h"
 
 namespace {
 
@@ -179,80 +180,77 @@ CTypeset::CTypeset(CSection* pSection)
 CTypeset::~CTypeset() {}
 
 CPVT_FloatRect CTypeset::CharArray() {
-  ASSERT(m_pSection);
+  m_rcRet = CPVT_FloatRect(0, 0, 0, 0);
+  if (m_pSection->m_LineArray.empty())
+    return m_rcRet;
+
+  float fNodeWidth = m_pVT->GetPlateWidth() /
+                     (m_pVT->m_nCharArray <= 0 ? 1 : m_pVT->m_nCharArray);
   float fLineAscent =
       m_pVT->GetFontAscent(m_pVT->GetDefaultFontIndex(), m_pVT->GetFontSize());
   float fLineDescent =
       m_pVT->GetFontDescent(m_pVT->GetDefaultFontIndex(), m_pVT->GetFontSize());
-  m_rcRet.Default();
-  float x = 0.0f, y = 0.0f;
-  float fNextWidth;
+  float x = 0.0f;
+  float y = m_pVT->GetLineLeading(m_pSection->m_SecInfo) + fLineAscent;
   int32_t nStart = 0;
-  float fNodeWidth = m_pVT->GetPlateWidth() /
-                     (m_pVT->m_nCharArray <= 0 ? 1 : m_pVT->m_nCharArray);
-  if (CLine* pLine = m_pSection->m_LineArray.GetAt(0)) {
-    x = 0.0f;
-    y += m_pVT->GetLineLeading(m_pSection->m_SecInfo);
-    y += fLineAscent;
-    nStart = 0;
-    switch (m_pVT->GetAlignment(m_pSection->m_SecInfo)) {
-      case 0:
-        pLine->m_LineInfo.fLineX = fNodeWidth * VARIABLETEXT_HALF;
-        break;
-      case 1:
-        nStart = (m_pVT->m_nCharArray - m_pSection->m_WordArray.GetSize()) / 2;
-        pLine->m_LineInfo.fLineX =
-            fNodeWidth * nStart - fNodeWidth * VARIABLETEXT_HALF;
-        break;
-      case 2:
-        nStart = m_pVT->m_nCharArray - m_pSection->m_WordArray.GetSize();
-        pLine->m_LineInfo.fLineX =
-            fNodeWidth * nStart - fNodeWidth * VARIABLETEXT_HALF;
-        break;
+  CLine* pLine = m_pSection->m_LineArray.front().get();
+  switch (m_pVT->GetAlignment(m_pSection->m_SecInfo)) {
+    case 0:
+      pLine->m_LineInfo.fLineX = fNodeWidth * VARIABLETEXT_HALF;
+      break;
+    case 1:
+      nStart = (m_pVT->m_nCharArray - m_pSection->m_WordArray.GetSize()) / 2;
+      pLine->m_LineInfo.fLineX =
+          fNodeWidth * nStart - fNodeWidth * VARIABLETEXT_HALF;
+      break;
+    case 2:
+      nStart = m_pVT->m_nCharArray - m_pSection->m_WordArray.GetSize();
+      pLine->m_LineInfo.fLineX =
+          fNodeWidth * nStart - fNodeWidth * VARIABLETEXT_HALF;
+      break;
+  }
+  for (int32_t w = 0, sz = m_pSection->m_WordArray.GetSize(); w < sz; w++) {
+    if (w >= m_pVT->m_nCharArray)
+      break;
+
+    float fNextWidth = 0;
+    if (CPVT_WordInfo* pNextWord = m_pSection->m_WordArray.GetAt(w + 1)) {
+      pNextWord->fWordTail = 0;
+      fNextWidth = m_pVT->GetWordWidth(*pNextWord);
     }
-    for (int32_t w = 0, sz = m_pSection->m_WordArray.GetSize(); w < sz; w++) {
-      if (w >= m_pVT->m_nCharArray) {
-        break;
-      }
-      fNextWidth = 0;
-      if (CPVT_WordInfo* pNextWord = m_pSection->m_WordArray.GetAt(w + 1)) {
-        pNextWord->fWordTail = 0;
-        fNextWidth = m_pVT->GetWordWidth(*pNextWord);
+    if (CPVT_WordInfo* pWord = m_pSection->m_WordArray.GetAt(w)) {
+      pWord->fWordTail = 0;
+      float fWordWidth = m_pVT->GetWordWidth(*pWord);
+      float fWordAscent = m_pVT->GetWordAscent(*pWord);
+      float fWordDescent = m_pVT->GetWordDescent(*pWord);
+      x = (float)(fNodeWidth * (w + nStart + 0.5) -
+                  fWordWidth * VARIABLETEXT_HALF);
+      pWord->fWordX = x;
+      pWord->fWordY = y;
+      if (w == 0) {
+        pLine->m_LineInfo.fLineX = x;
       }
-      if (CPVT_WordInfo* pWord = m_pSection->m_WordArray.GetAt(w)) {
+      if (w != m_pSection->m_WordArray.GetSize() - 1) {
+        pWord->fWordTail =
+            (fNodeWidth - (fWordWidth + fNextWidth) * VARIABLETEXT_HALF > 0
+                 ? fNodeWidth - (fWordWidth + fNextWidth) * VARIABLETEXT_HALF
+                 : 0);
+      } else {
         pWord->fWordTail = 0;
-        float fWordWidth = m_pVT->GetWordWidth(*pWord);
-        float fWordAscent = m_pVT->GetWordAscent(*pWord);
-        float fWordDescent = m_pVT->GetWordDescent(*pWord);
-        x = (float)(fNodeWidth * (w + nStart + 0.5) -
-                    fWordWidth * VARIABLETEXT_HALF);
-        pWord->fWordX = x;
-        pWord->fWordY = y;
-        if (w == 0) {
-          pLine->m_LineInfo.fLineX = x;
-        }
-        if (w != m_pSection->m_WordArray.GetSize() - 1) {
-          pWord->fWordTail =
-              (fNodeWidth - (fWordWidth + fNextWidth) * VARIABLETEXT_HALF > 0
-                   ? fNodeWidth - (fWordWidth + fNextWidth) * VARIABLETEXT_HALF
-                   : 0);
-        } else {
-          pWord->fWordTail = 0;
-        }
-        x += fWordWidth;
-        fLineAscent = std::max(fLineAscent, fWordAscent);
-        fLineDescent = std::min(fLineDescent, fWordDescent);
       }
+      x += fWordWidth;
+      fLineAscent = std::max(fLineAscent, fWordAscent);
+      fLineDescent = std::min(fLineDescent, fWordDescent);
     }
-    pLine->m_LineInfo.nBeginWordIndex = 0;
-    pLine->m_LineInfo.nEndWordIndex = m_pSection->m_WordArray.GetSize() - 1;
-    pLine->m_LineInfo.fLineY = y;
-    pLine->m_LineInfo.fLineWidth = x - pLine->m_LineInfo.fLineX;
-    pLine->m_LineInfo.fLineAscent = fLineAscent;
-    pLine->m_LineInfo.fLineDescent = fLineDescent;
-    y -= fLineDescent;
   }
-  return m_rcRet = CPVT_FloatRect(0, 0, x, y);
+  pLine->m_LineInfo.nBeginWordIndex = 0;
+  pLine->m_LineInfo.nEndWordIndex = m_pSection->m_WordArray.GetSize() - 1;
+  pLine->m_LineInfo.fLineY = y;
+  pLine->m_LineInfo.fLineWidth = x - pLine->m_LineInfo.fLineX;
+  pLine->m_LineInfo.fLineAscent = fLineAscent;
+  pLine->m_LineInfo.fLineDescent = fLineDescent;
+  m_rcRet = CPVT_FloatRect(0, 0, x, y - fLineDescent);
+  return m_rcRet;
 }
 
 CFX_SizeF CTypeset::GetEditSize(float fFontSize) {
@@ -264,9 +262,8 @@ CFX_SizeF CTypeset::GetEditSize(float fFontSize) {
 
 CPVT_FloatRect CTypeset::Typeset() {
   ASSERT(m_pVT);
-  m_pSection->m_LineArray.Empty();
+  m_pSection->m_LineArray.clear();
   SplitLines(true, 0.0f);
-  m_pSection->m_LineArray.Clear();
   OutputLines();
   return m_rcRet;
 }
@@ -439,54 +436,54 @@ void CTypeset::OutputLines() {
   fMaxX = fMinX + m_rcRet.Width();
   fMinY = 0.0f;
   fMaxY = m_rcRet.Height();
-  int32_t nTotalLines = m_pSection->m_LineArray.GetSize();
+  int32_t nTotalLines =
+      pdfium::CollectionSize<int32_t>(m_pSection->m_LineArray);
   if (nTotalLines > 0) {
     m_pSection->m_SecInfo.nTotalLine = nTotalLines;
     for (int32_t l = 0; l < nTotalLines; l++) {
-      if (CLine* pLine = m_pSection->m_LineArray.GetAt(l)) {
-        switch (m_pVT->GetAlignment(m_pSection->m_SecInfo)) {
-          default:
-          case 0:
-            fPosX = 0;
-            break;
-          case 1:
-            fPosX = (fTypesetWidth - pLine->m_LineInfo.fLineWidth) *
-                    VARIABLETEXT_HALF;
-            break;
-          case 2:
-            fPosX = fTypesetWidth - pLine->m_LineInfo.fLineWidth;
-            break;
-        }
-        fPosX += fLineIndent;
-        fPosY += m_pVT->GetLineLeading(m_pSection->m_SecInfo);
-        fPosY += pLine->m_LineInfo.fLineAscent;
-        pLine->m_LineInfo.fLineX = fPosX - fMinX;
-        pLine->m_LineInfo.fLineY = fPosY - fMinY;
-        for (int32_t w = pLine->m_LineInfo.nBeginWordIndex;
-             w <= pLine->m_LineInfo.nEndWordIndex; w++) {
-          if (CPVT_WordInfo* pWord = m_pSection->m_WordArray.GetAt(w)) {
-            pWord->fWordX = fPosX - fMinX;
-            if (pWord->pWordProps) {
-              switch (pWord->pWordProps->nScriptType) {
-                default:
-                case CPDF_VariableText::ScriptType::Normal:
-                  pWord->fWordY = fPosY - fMinY;
-                  break;
-                case CPDF_VariableText::ScriptType::Super:
-                  pWord->fWordY = fPosY - m_pVT->GetWordAscent(*pWord) - fMinY;
-                  break;
-                case CPDF_VariableText::ScriptType::Sub:
-                  pWord->fWordY = fPosY - m_pVT->GetWordDescent(*pWord) - fMinY;
-                  break;
-              }
-            } else {
-              pWord->fWordY = fPosY - fMinY;
+      CLine* pLine = m_pSection->m_LineArray[l].get();
+      switch (m_pVT->GetAlignment(m_pSection->m_SecInfo)) {
+        default:
+        case 0:
+          fPosX = 0;
+          break;
+        case 1:
+          fPosX = (fTypesetWidth - pLine->m_LineInfo.fLineWidth) *
+                  VARIABLETEXT_HALF;
+          break;
+        case 2:
+          fPosX = fTypesetWidth - pLine->m_LineInfo.fLineWidth;
+          break;
+      }
+      fPosX += fLineIndent;
+      fPosY += m_pVT->GetLineLeading(m_pSection->m_SecInfo);
+      fPosY += pLine->m_LineInfo.fLineAscent;
+      pLine->m_LineInfo.fLineX = fPosX - fMinX;
+      pLine->m_LineInfo.fLineY = fPosY - fMinY;
+      for (int32_t w = pLine->m_LineInfo.nBeginWordIndex;
+           w <= pLine->m_LineInfo.nEndWordIndex; w++) {
+        if (CPVT_WordInfo* pWord = m_pSection->m_WordArray.GetAt(w)) {
+          pWord->fWordX = fPosX - fMinX;
+          if (pWord->pWordProps) {
+            switch (pWord->pWordProps->nScriptType) {
+              default:
+              case CPDF_VariableText::ScriptType::Normal:
+                pWord->fWordY = fPosY - fMinY;
+                break;
+              case CPDF_VariableText::ScriptType::Super:
+                pWord->fWordY = fPosY - m_pVT->GetWordAscent(*pWord) - fMinY;
+                break;
+              case CPDF_VariableText::ScriptType::Sub:
+                pWord->fWordY = fPosY - m_pVT->GetWordDescent(*pWord) - fMinY;
+                break;
             }
-            fPosX += m_pVT->GetWordWidth(*pWord);
+          } else {
+            pWord->fWordY = fPosY - fMinY;
           }
+          fPosX += m_pVT->GetWordWidth(*pWord);
         }
-        fPosY -= pLine->m_LineInfo.fLineDescent;
       }
+      fPosY -= pLine->m_LineInfo.fLineDescent;
     }
   }
   m_rcRet = CPVT_FloatRect(fMinX, fMinY, fMaxX, fMaxY);