Overload QPDF_Null::create to take a child object description

4 files changed, 39 insertions, 15 deletions

diff --git a/libqpdf/QPDFObjectHandle.cc b/libqpdf/QPDFObjectHandle.cc
index cbe42995..d474dcce 100644
--- a/libqpdf/QPDFObjectHandle.cc
+++ b/libqpdf/QPDFObjectHandle.cc
@@ -802,12 +802,10 @@ QPDFObjectHandle::getArrayNItems()
 QPDFObjectHandle
 QPDFObjectHandle::getArrayItem(int n)
 {
-    QPDFObjectHandle result;
     auto array = asArray();
     if (array && (n < array->getNItems()) && (n >= 0)) {
-        result = array->getItem(n);
+        return array->getItem(n);
     } else {
-        result = newNull();
         if (array) {
             objectWarning("returning null for out of bounds array access");
             QTC::TC("qpdf", "QPDFObjectHandle array bounds");
@@ -817,9 +815,8 @@ QPDFObjectHandle::getArrayItem(int n)
         }
         static auto constexpr msg =
             " -> null returned from invalid array access"sv;
-        result.obj->setChildDescription(obj, msg, "");
+        return QPDF_Null::create(obj, msg, "");
     }
-    return result;
 }
 
 bool
@@ -1028,19 +1025,15 @@ QPDFObjectHandle::hasKey(std::string const& key)
 QPDFObjectHandle
 QPDFObjectHandle::getKey(std::string const& key)
 {
-    QPDFObjectHandle result;
-    auto dict = asDictionary();
-    if (dict) {
-        result = dict->getKey(key);
+    if (auto dict = asDictionary()) {
+        return dict->getKey(key);
     } else {
         typeWarning("dictionary", "returning null for attempted key retrieval");
         QTC::TC("qpdf", "QPDFObjectHandle dictionary null for getKey");
-        result = newNull();
         static auto constexpr msg =
             " -> null returned from getting key $VD from non-Dictionary"sv;
-        result.obj->setChildDescription(obj, msg, key);
+        return QPDF_Null::create(obj, msg, "");
     }
-    return result;
 }
 
 QPDFObjectHandle
diff --git a/libqpdf/QPDF_Dictionary.cc b/libqpdf/QPDF_Dictionary.cc
index f45c00c6..43ad8a85 100644
--- a/libqpdf/QPDF_Dictionary.cc
+++ b/libqpdf/QPDF_Dictionary.cc
@@ -2,6 +2,7 @@
 
 #include <qpdf/QPDFObject_private.hh>
 #include <qpdf/QPDF_Name.hh>
+#include <qpdf/QPDF_Null.hh>
 
 using namespace std::literals;
 
@@ -100,10 +101,8 @@ QPDF_Dictionary::getKey(std::string const& key)
         // May be a null object
         return item->second;
     } else {
-        auto null = QPDFObjectHandle::newNull();
         static auto constexpr msg = " -> dictionary key $VD"sv;
-        null.getObj()->setChildDescription(shared_from_this(), msg, key);
-        return null;
+        return QPDF_Null::create(shared_from_this(), msg, key);
     }
 }
 
diff --git a/libqpdf/QPDF_Null.cc b/libqpdf/QPDF_Null.cc
index 6ec4556c..a82f23c0 100644
--- a/libqpdf/QPDF_Null.cc
+++ b/libqpdf/QPDF_Null.cc
@@ -1,5 +1,7 @@
 #include <qpdf/QPDF_Null.hh>
 
+#include <qpdf/QPDFObject_private.hh>
+
 QPDF_Null::QPDF_Null() :
     QPDFValue(::ot_null, "null")
 {
@@ -12,6 +14,28 @@ QPDF_Null::create()
 }
 
 std::shared_ptr<QPDFObject>
+QPDF_Null::create(
+    std::shared_ptr<QPDFObject> parent,
+    std::string_view const& static_descr,
+    std::string var_descr)
+{
+    auto n = do_create(new QPDF_Null());
+    n->setChildDescription(parent, static_descr, var_descr);
+    return n;
+}
+
+std::shared_ptr<QPDFObject>
+QPDF_Null::create(
+    std::shared_ptr<QPDFValue> parent,
+    std::string_view const& static_descr,
+    std::string var_descr)
+{
+    auto n = do_create(new QPDF_Null());
+    n->setChildDescription(parent, static_descr, var_descr);
+    return n;
+}
+
+std::shared_ptr<QPDFObject>
 QPDF_Null::copy(bool shallow)
 {
     return create();
diff --git a/libqpdf/qpdf/QPDF_Null.hh b/libqpdf/qpdf/QPDF_Null.hh
index 1a92b214..2bbb3db5 100644
--- a/libqpdf/qpdf/QPDF_Null.hh
+++ b/libqpdf/qpdf/QPDF_Null.hh
@@ -8,6 +8,14 @@ class QPDF_Null: public QPDFValue
   public:
     virtual ~QPDF_Null() = default;
     static std::shared_ptr<QPDFObject> create();
+    static std::shared_ptr<QPDFObject> create(
+        std::shared_ptr<QPDFObject> parent,
+        std::string_view const& static_descr,
+        std::string var_descr);
+    static std::shared_ptr<QPDFObject> create(
+        std::shared_ptr<QPDFValue> parent,
+        std::string_view const& static_descr,
+        std::string var_descr);
     virtual std::shared_ptr<QPDFObject> copy(bool shallow = false);
     virtual std::string unparse();
     virtual JSON getJSON(int json_version);