From 2d11e4dd9b2ca5122cb7fc04b82405eb3c9d5fdd Mon Sep 17 00:00:00 2001
From: m-holger <m.holger@qpdf.org>
Date: Sat, 8 Nov 2025 00:26:36 +0000
Subject: [PATCH] Refactor null object handling across helpers to use the `Null` class for consistent and simplified temporary null management. Clean up unused test coverage markers.

---
 libqpdf/QPDFAcroFormDocumentHelper.cc     | 7 +++----
 libqpdf/QPDFAnnotationObjectHelper.cc     | 8 ++------
 libqpdf/QPDFEmbeddedFileDocumentHelper.cc | 8 ++++----
 libqpdf/QPDFFileSpecObjectHelper.cc       | 2 +-
 qpdf/qpdf.testcov                         | 4 ----
 5 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/libqpdf/QPDFAcroFormDocumentHelper.cc b/libqpdf/QPDFAcroFormDocumentHelper.cc
index 2f0d629..4fb3ec3 100644
--- a/libqpdf/QPDFAcroFormDocumentHelper.cc
+++ b/libqpdf/QPDFAcroFormDocumentHelper.cc
@@ -252,16 +252,15 @@ QPDFFormFieldObjectHelper
 QPDFAcroFormDocumentHelper::getFieldForAnnotation(QPDFAnnotationObjectHelper h)
 {
     QPDFObjectHandle oh = h.getObjectHandle();
-    QPDFFormFieldObjectHelper result(QPDFObjectHandle::newNull());
     if (!oh.isDictionaryOfType("", "/Widget")) {
-        return result;
+        return Null::temp();
     }
     analyze();
     QPDFObjGen og(oh.getObjGen());
     if (m->annotation_to_field.contains(og)) {
-        result = m->annotation_to_field[og];
+        return m->annotation_to_field[og];
     }
-    return result;
+    return Null::temp();
 }
 
 void
diff --git a/libqpdf/QPDFAnnotationObjectHelper.cc b/libqpdf/QPDFAnnotationObjectHelper.cc
index ce2b12d..63e3628 100644
--- a/libqpdf/QPDFAnnotationObjectHelper.cc
+++ b/libqpdf/QPDFAnnotationObjectHelper.cc
@@ -56,20 +56,16 @@ QPDFAnnotationObjectHelper::getAppearanceStream(std::string const& which, std::s
             // appearance stream when /AP is a dictionary, but files have been seen in the wild
             // where Appearance State is `/N` and `/AP` is a stream. Therefore, if `which` points to
             // a stream, disregard state and just use the stream. See qpdf issue #949 for details.
-            QTC::TC("qpdf", "QPDFAnnotationObjectHelper AP stream");
             return ap_sub;
         }
-        if (ap_sub.isDictionary() && (!desired_state.empty())) {
-            QTC::TC("qpdf", "QPDFAnnotationObjectHelper AP dictionary");
+        if (ap_sub.isDictionary() && !desired_state.empty()) {
             QPDFObjectHandle ap_sub_val = ap_sub.getKey(desired_state);
             if (ap_sub_val.isStream()) {
-                QTC::TC("qpdf", "QPDFAnnotationObjectHelper AP sub stream");
                 return ap_sub_val;
             }
         }
     }
-    QTC::TC("qpdf", "QPDFAnnotationObjectHelper AP null");
-    return QPDFObjectHandle::newNull();
+    return Null::temp();
 }
 
 std::string
diff --git a/libqpdf/QPDFEmbeddedFileDocumentHelper.cc b/libqpdf/QPDFEmbeddedFileDocumentHelper.cc
index bdc86ad..d44c1ff 100644
--- a/libqpdf/QPDFEmbeddedFileDocumentHelper.cc
+++ b/libqpdf/QPDFEmbeddedFileDocumentHelper.cc
@@ -1,6 +1,7 @@
 #include <qpdf/QPDFEmbeddedFileDocumentHelper.hh>
 
 #include <qpdf/QPDFNameTreeObjectHelper.hh>
+#include <qpdf/QPDFObjectHandle_private.hh>
 #include <qpdf/QPDF_private.hh>
 
 // File attachments are stored in the /EmbeddedFiles (name tree) key of the /Names dictionary from
@@ -143,11 +144,10 @@ QPDFEmbeddedFileDocumentHelper::removeEmbeddedFile(std::string const& name)
     if (iter == m->embedded_files->end()) {
         return false;
     }
-    auto oh = iter->second;
-    iter.remove();
-    if (oh.isIndirect()) {
-        qpdf.replaceObject(oh.getObjGen(), QPDFObjectHandle::newNull());
+    if (iter->second.indirect()) {
+        qpdf.replaceObject(iter->second, Null());
     }
+    iter.remove();
 
     return true;
 }
diff --git a/libqpdf/QPDFFileSpecObjectHelper.cc b/libqpdf/QPDFFileSpecObjectHelper.cc
index d92aac4..570b056 100644
--- a/libqpdf/QPDFFileSpecObjectHelper.cc
+++ b/libqpdf/QPDFFileSpecObjectHelper.cc
@@ -76,7 +76,7 @@ QPDFFileSpecObjectHelper::getEmbeddedFileStream(std::string const& key)
             }
         }
     }
-    return QPDFObjectHandle::newNull();
+    return Null::temp();
 }
 
 QPDFObjectHandle
diff --git a/qpdf/qpdf.testcov b/qpdf/qpdf.testcov
index 2c10208..8c9646e 100644
--- a/qpdf/qpdf.testcov
+++ b/qpdf/qpdf.testcov
@@ -181,10 +181,6 @@ QPDFFormFieldObjectHelper TU absent 0
 QPDFFormFieldObjectHelper TM absent 0
 QPDFFormFieldObjectHelper Q present 1
 QPDFFormFieldObjectHelper DA present 1
-QPDFAnnotationObjectHelper AP stream 0
-QPDFAnnotationObjectHelper AP dictionary 0
-QPDFAnnotationObjectHelper AP sub stream 0
-QPDFAnnotationObjectHelper AP null 0
 QPDFAcroFormDocumentHelper field found 1
 QPDFAcroFormDocumentHelper annotation found 1
 QPDFJob automatically set keep files open 1
--
libgit2 0.21.4