Rename GetOccur to GetOccurIfExists

This CL makes it explicit that GetOccurIfExists can return nullptr and
fixes up the call sites.

Change-Id: I542d0098aa316632239df7f1a5796b4ffe6ba202
Reviewed-on: https://pdfium-review.googlesource.com/22676
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

6 files changed, 26 insertions, 14 deletions

diff --git a/fxjs/xfa/cjx_instancemanager.cpp b/fxjs/xfa/cjx_instancemanager.cpp
index f6aef37c16..a5e3295c9b 100644
--- a/fxjs/xfa/cjx_instancemanager.cpp
+++ b/fxjs/xfa/cjx_instancemanager.cpp
@@ -33,13 +33,14 @@ CJX_InstanceManager::CJX_InstanceManager(CXFA_InstanceManager* mgr)
 CJX_InstanceManager::~CJX_InstanceManager() {}
 
 int32_t CJX_InstanceManager::SetInstances(int32_t iDesired) {
-  CXFA_Occur* occur = GetXFANode()->GetOccur();
-  if (iDesired < occur->GetMin()) {
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  int32_t iMin = occur ? occur->GetMin() : CXFA_Occur::kDefaultMin;
+  if (iDesired < iMin) {
     ThrowTooManyOccurancesException(L"min");
     return 1;
   }
 
-  int32_t iMax = occur->GetMax();
+  int32_t iMax = occur ? occur->GetMax() : CXFA_Occur::kDefaultMax;
   if (iMax >= 0 && iDesired > iMax) {
     ThrowTooManyOccurancesException(L"max");
     return 2;
@@ -153,7 +154,8 @@ CJS_Return CJX_InstanceManager::removeInstance(
   if (iIndex < 0 || iIndex >= iCount)
     return CJS_Return(JSGetStringFromID(JSMessage::kInvalidInputError));
 
-  int32_t iMin = GetXFANode()->GetOccur()->GetMin();
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  int32_t iMin = occur ? occur->GetMin() : CXFA_Occur::kDefaultMin;
   if (iCount - 1 < iMin)
     return CJS_Return(JSGetStringFromID(JSMessage::kTooManyOccurances));
 
@@ -199,7 +201,8 @@ CJS_Return CJX_InstanceManager::addInstance(
     fFlags = runtime->ToBoolean(params[0]);
 
   int32_t iCount = GetXFANode()->GetCount();
-  int32_t iMax = GetXFANode()->GetOccur()->GetMax();
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  int32_t iMax = occur ? occur->GetMax() : CXFA_Occur::kDefaultMax;
   if (iMax >= 0 && iCount >= iMax)
     return CJS_Return(JSGetStringFromID(JSMessage::kTooManyOccurances));
 
@@ -240,7 +243,8 @@ CJS_Return CJX_InstanceManager::insertInstance(
   if (iIndex < 0 || iIndex > iCount)
     return CJS_Return(JSGetStringFromID(JSMessage::kInvalidInputError));
 
-  int32_t iMax = GetXFANode()->GetOccur()->GetMax();
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  int32_t iMax = occur ? occur->GetMax() : CXFA_Occur::kDefaultMax;
   if (iMax >= 0 && iCount >= iMax)
     return CJS_Return(JSGetStringFromID(JSMessage::kInvalidInputError));
 
@@ -272,7 +276,8 @@ void CJX_InstanceManager::max(CFXJSE_Value* pValue,
     ThrowInvalidPropertyException();
     return;
   }
-  pValue->SetInteger(GetXFANode()->GetOccur()->GetMax());
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  pValue->SetInteger(occur ? occur->GetMax() : CXFA_Occur::kDefaultMax);
 }
 
 void CJX_InstanceManager::min(CFXJSE_Value* pValue,
@@ -282,7 +287,8 @@ void CJX_InstanceManager::min(CFXJSE_Value* pValue,
     ThrowInvalidPropertyException();
     return;
   }
-  pValue->SetInteger(GetXFANode()->GetOccur()->GetMin());
+  CXFA_Occur* occur = GetXFANode()->GetOccurIfExists();
+  pValue->SetInteger(occur ? occur->GetMin() : CXFA_Occur::kDefaultMin);
 }
 
 void CJX_InstanceManager::count(CFXJSE_Value* pValue,
diff --git a/xfa/fxfa/cxfa_widgetacc.cpp b/xfa/fxfa/cxfa_widgetacc.cpp
index 9f9b29fe3b..efcd320a03 100644
--- a/xfa/fxfa/cxfa_widgetacc.cpp
+++ b/xfa/fxfa/cxfa_widgetacc.cpp
@@ -551,8 +551,8 @@ bool CXFA_WidgetAcc::CalculateFieldAutoSize(CXFA_FFDoc* doc, CFX_SizeF& size) {
   size.height += rtUIMargin.top + rtUIMargin.height;
   if (szCap.width > 0 && szCap.height > 0) {
     CXFA_Caption* caption = m_pNode->GetCaptionIfExists();
-    XFA_AttributeEnum placement =
-        caption ? caption->GetPlacementType() : XFA_AttributeEnum::Left;
+    XFA_AttributeEnum placement = caption ? caption->GetPlacementType()
+                                          : CXFA_Caption::kDefaultPlacementType;
     switch (placement) {
       case XFA_AttributeEnum::Left:
       case XFA_AttributeEnum::Right:
@@ -655,8 +655,8 @@ bool CXFA_WidgetAcc::CalculateTextEditAutoSize(CXFA_FFDoc* doc,
     XFA_AttributeEnum iCapPlacement = XFA_AttributeEnum::Unknown;
     if (bCapExit) {
       CXFA_Caption* caption = m_pNode->GetCaptionIfExists();
-      iCapPlacement =
-          caption ? caption->GetPlacementType() : XFA_AttributeEnum::Left;
+      iCapPlacement = caption ? caption->GetPlacementType()
+                              : CXFA_Caption::kDefaultPlacementType;
       switch (iCapPlacement) {
         case XFA_AttributeEnum::Left:
         case XFA_AttributeEnum::Right:
diff --git a/xfa/fxfa/parser/cxfa_caption.h b/xfa/fxfa/parser/cxfa_caption.h
index 11c1cec3f4..1b634d8f5c 100644
--- a/xfa/fxfa/parser/cxfa_caption.h
+++ b/xfa/fxfa/parser/cxfa_caption.h
@@ -15,6 +15,9 @@ class CXFA_Value;
 
 class CXFA_Caption : public CXFA_Node {
  public:
+  static constexpr XFA_AttributeEnum kDefaultPlacementType =
+      XFA_AttributeEnum::Left;
+
   CXFA_Caption(CXFA_Document* doc, XFA_PacketType packet);
   ~CXFA_Caption() override;
 
diff --git a/xfa/fxfa/parser/cxfa_node.cpp b/xfa/fxfa/parser/cxfa_node.cpp
index d2c1e6fe8b..12a6ee4a0a 100644
--- a/xfa/fxfa/parser/cxfa_node.cpp
+++ b/xfa/fxfa/parser/cxfa_node.cpp
@@ -1060,7 +1060,7 @@ CXFA_Node* CXFA_Node::GetInstanceMgrOfSubform() {
   return pInstanceMgr;
 }
 
-CXFA_Occur* CXFA_Node::GetOccur() {
+CXFA_Occur* CXFA_Node::GetOccurIfExists() {
   return GetFirstChildByClass<CXFA_Occur>(XFA_Element::Occur);
 }
 
diff --git a/xfa/fxfa/parser/cxfa_node.h b/xfa/fxfa/parser/cxfa_node.h
index 1972da9183..f4ff51382f 100644
--- a/xfa/fxfa/parser/cxfa_node.h
+++ b/xfa/fxfa/parser/cxfa_node.h
@@ -224,7 +224,7 @@ class CXFA_Node : public CXFA_Object {
   int32_t GetNodeSameClassIndex() const;
   CXFA_Node* GetInstanceMgrOfSubform();
 
-  CXFA_Occur* GetOccur();
+  CXFA_Occur* GetOccurIfExists();
 
   Optional<bool> GetDefaultBoolean(XFA_Attribute attr) const;
   Optional<int32_t> GetDefaultInteger(XFA_Attribute attr) const;
diff --git a/xfa/fxfa/parser/cxfa_occur.h b/xfa/fxfa/parser/cxfa_occur.h
index 3367b07ae5..070c15ca46 100644
--- a/xfa/fxfa/parser/cxfa_occur.h
+++ b/xfa/fxfa/parser/cxfa_occur.h
@@ -13,6 +13,9 @@
 
 class CXFA_Occur : public CXFA_Node {
  public:
+  static constexpr int32_t kDefaultMax = 1;
+  static constexpr int32_t kDefaultMin = 1;
+
   CXFA_Occur(CXFA_Document* doc, XFA_PacketType packet);
   ~CXFA_Occur() override;