Fix a .qetz that cannot be opened after only a folio's title changed

With a .qetz and lazy folios (both the default), changing only the
title, author, date or revision of a folio holding a picture, while that
folio was not displayed, then saving, gave a .qetz that refused to open:
'picture "images/<sha>.png" is missing'.

Such a folio is saved from its items as read, with its new header
(Diagram::deferredXmlWithHeader()). Read from a .qetz, its <image> names
its picture's file (qetz-file) instead of holding the picture, and
QetContainer::split() takes out only pictures held inline: the file was
never written, while the folio still named it. The folio now gets its
pictures written in, from the bytes the project keeps
(QETProject::containerPicture()), as a built folio writes them.

On master, a picture on folio 2 of grafcet, iso_sfc_example, 741,
tremie_vibrante or Projet_vierge is lost this way; found on three forum
projects by comparing lazy saves with saves of every folio built. Saving
as .qet was not affected.

New tst_qetzheaderpictures (grafcet.qet: picture on folio 2, saved as
.qetz; its title changed with folios built when needed; reopened with
its picture and title): fails without this change ("picture ... is
missing"). ctest 107/107.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

sources/container/qetcontainer.cpp

@@ -208,6 +208,13 @@ QString QetContainer::pictureFile(const QDomElement &image)
 	return image.attribute(ImageFileAttribute);
 }
 
+void QetContainer::inlinePicture(QDomElement image, const QByteArray &bytes)
+{
+	image.removeAttribute(ImageFileAttribute);
+	image.insertBefore(image.ownerDocument().createTextNode(QString::fromLatin1(bytes.toBase64())),
+					   image.firstChild());
+}
+
 /**
 	@brief QetContainer::ownUuids
 	@return true if every folio, symbol and wire of @p project has a uuid

sources/container/qetcontainer.h

@@ -84,6 +84,9 @@ namespace QetContainer
 				 QString *error = nullptr);
 		/// The file join() left the picture of @p image in, or an empty string
 	QString pictureFile(const QDomElement &image);
+		/// @p image, which names its picture's file (pictureFile()), given
+		/// the picture itself, @p bytes, as a document read whole has it
+	void inlinePicture(QDomElement image, const QByteArray &bytes);
 
 		/// Take what QElectroTech computes out of a folio (format 4)
 	void dropComputed(QDomElement diagram, bool terminal_lists);

sources/diagram.cpp

@@ -881,6 +881,17 @@ QDomElement Diagram::deferredXmlWithHeader(QDomDocument &document)
 	for (QDomElement child = items.firstChildElement() ; !child.isNull() ; child = child.nextSiblingElement())
 		if (!header_children.contains(child.tagName()))
 			folio.appendChild(document.importNode(child, true));
+		//Its pictures written in, as building it writes them. A folio read
+		//from a .qetz names its pictures' files instead, which the next
+		//.qetz written from this document would leave out: that project
+		//then refused to open, "picture ... is missing" (F118).
+	for (QDomElement image : QET::findInDomElement(folio, QStringLiteral("images"), QStringLiteral("image"))) {
+		const QString file = QetContainer::pictureFile(image);
+		if (file.isEmpty() || !m_project) continue;
+		const QByteArray bytes = m_project->containerPicture(file);
+		if (!bytes.isEmpty())
+			QetContainer::inlinePicture(image, bytes);
+	}
 	return folio;
 }
 

tests/qttest/CMakeLists.txt

@@ -943,6 +943,18 @@ if(QET_HAS_SCRIPTING)
     "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\""
     "QET_EXAMPLES_DIR=\"${QET_DIR}/examples\"")
 
+  # A .qetz folio whose title only changed keeps its pictures when saved
+  # with folios built when needed (F118), on examples/grafcet.qet.
+  add_executable(
+    tst_qetzheaderpictures
+    tst_qetzheaderpictures.cpp)
+  add_test(NAME tst_qetzheaderpictures COMMAND tst_qetzheaderpictures)
+  add_dependencies(tst_qetzheaderpictures qelectrotech)
+  target_link_libraries(tst_qetzheaderpictures PRIVATE Qt::Test)
+  target_compile_definitions(tst_qetzheaderpictures PRIVATE
+    "QET_TEST_BINARY_PATH=\"$<TARGET_FILE:qelectrotech>\""
+    "QET_EXAMPLES_DIR=\"${QET_DIR}/examples\"")
+
   # qet.elementTerminals() lists each terminal's uuid and qet.terminalIndex()
   # turns element uuid + terminal uuid back into the index the conductor
   # calls take, on examples/perceuse.qet (two terminals at one point).

tests/qttest/tst_qetzheaderpictures.cpp

@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <QtTest>
+
+#include <QDir>
+#include <QFile>
+#include <QProcess>
+#include <QProcessEnvironment>
+#include <QTemporaryDir>
+
+// A folio of a .qetz whose title only changed is saved from its items as
+// read, not built (Diagram::deferredXmlWithHeader()). Those items name
+// their pictures' files in the .qetz, which the new .qetz left out: the
+// project saved then refused to open, 'picture "images/..." is missing'
+// (FINDINGS F118). Runs scripts through the real binary's --run on a copy
+// of examples/grafcet.qet given a picture on its second folio.
+class tst_qetzheaderpictures : public QObject
+{
+	Q_OBJECT
+
+	QTemporaryDir m_dir;
+
+		// Run @p script on @p project; its output
+	QString run(const QString &script, const QString &project, bool every_folio_built)
+	{
+		const QString path = m_dir.filePath(QStringLiteral("script.js"));
+		QFile f(path);
+		if (!f.open(QIODevice::WriteOnly | QIODevice::Truncate)) return QString();
+		f.write(script.toUtf8());
+		f.close();
+		const QString home = m_dir.filePath(QStringLiteral("home"));
+		QDir().mkpath(home);
+		QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+		env.insert(QStringLiteral("QT_QPA_PLATFORM"), QStringLiteral("offscreen"));
+		env.insert(QStringLiteral("QET_ENABLE_SCRIPTING"), QStringLiteral("1"));
+		env.insert(QStringLiteral("HOME"), home);
+		env.insert(QStringLiteral("XDG_CONFIG_HOME"), home + QStringLiteral("/config"));
+		env.insert(QStringLiteral("XDG_DATA_HOME"), home + QStringLiteral("/data"));
+		env.insert(QStringLiteral("TMPDIR"), m_dir.path());
+		if (every_folio_built)
+			env.insert(QStringLiteral("QET_EAGER_FOLIOS"), QStringLiteral("1"));
+		else
+			env.remove(QStringLiteral("QET_EAGER_FOLIOS"));
+		QProcess proc;
+		proc.setProcessEnvironment(env);
+		proc.start(QStringLiteral(QET_TEST_BINARY_PATH), {QStringLiteral("--run"), path, project});
+		proc.waitForFinished(120000);
+		return QString::fromUtf8(proc.readAllStandardOutput() + proc.readAllStandardError());
+	}
+
+private slots:
+	void initTestCase()
+	{
+		QVERIFY(m_dir.isValid());
+		QVERIFY(QFile::exists(QStringLiteral(QET_TEST_BINARY_PATH)));
+	}
+
+	void titleChangeKeepsPictures()
+	{
+			// A 1x1 PNG
+		const QString png = m_dir.filePath(QStringLiteral("dot.png"));
+		QFile p(png);
+		QVERIFY(p.open(QIODevice::WriteOnly));
+		p.write(QByteArray::fromBase64("iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg=="));
+		p.close();
+		const QString with_picture = m_dir.filePath(QStringLiteral("picture.qetz"));
+		const QString titled = m_dir.filePath(QStringLiteral("titled.qetz"));
+		QString out = run(QStringLiteral("qet.log('ADDED ' + qet.addImage(1, '%1', 100, 100));"
+										 "qet.save('%2');").arg(png, with_picture),
+						  QStringLiteral(QET_EXAMPLES_DIR "/grafcet.qet"), true);
+		QVERIFY2(out.contains(QStringLiteral("ADDED 0")), qPrintable(out));
+		QVERIFY(QFile::exists(with_picture));
+
+			// Only the title of the folio with the picture, folios built
+			// when needed
+		out = run(QStringLiteral("qet.log('SET ' + qet.setFolioProperty(1, 'title', 'Edited'));"
+								 "qet.save('%1');").arg(titled), with_picture, false);
+		QVERIFY2(out.contains(QStringLiteral("SET true")), qPrintable(out));
+		QVERIFY(QFile::exists(titled));
+
+			// Opens, with its picture and the new title
+		out = run(QStringLiteral("qet.log('PICTURES ' + qet.images(1).length);"
+								 "qet.log('TITLE ' + qet.folioTitle(1));"), titled, true);
+		QVERIFY2(out.contains(QStringLiteral("PICTURES 1")), qPrintable(out));
+		QVERIFY2(out.contains(QStringLiteral("TITLE Edited")), qPrintable(out));
+	}
+};
+
+QTEST_APPLESS_MAIN(tst_qetzheaderpictures)
+
+#include "tst_qetzheaderpictures.moc"