QDoc: Extract ManifestWriter from HTML generator

Fixes: QTBUG-86390
Change-Id: I9cdcb591bbd1cf6beccf27e53ab9af06b87ed4be
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

7 files changed, 412 insertions, 284 deletions

diff --git a/src/qdoc/.prev_CMakeLists.txt b/src/qdoc/.prev_CMakeLists.txt
index eebdf59a1..e65c0e9a4 100644
--- a/src/qdoc/.prev_CMakeLists.txt
+++ b/src/qdoc/.prev_CMakeLists.txt
@@ -42,6 +42,7 @@ qt_add_tool(${target_name}
         loggingcategory.h
         macro.h
         main.cpp
+        manifestwriter.cpp manifestwriter.h
         namespacenode.cpp namespacenode.h
         node.cpp node.h
         openedlist.cpp openedlist.h
diff --git a/src/qdoc/CMakeLists.txt b/src/qdoc/CMakeLists.txt
index bc7e29d54..f5904e29b 100644
--- a/src/qdoc/CMakeLists.txt
+++ b/src/qdoc/CMakeLists.txt
@@ -50,6 +50,7 @@ qt_add_tool(${target_name}
         loggingcategory.h
         macro.h
         main.cpp
+        manifestwriter.cpp manifestwriter.h
         namespacenode.cpp namespacenode.h
         node.cpp node.h
         openedlist.cpp openedlist.h
diff --git a/src/qdoc/htmlgenerator.cpp b/src/qdoc/htmlgenerator.cpp
index 6dc7dc93d..3cc08c84b 100644
--- a/src/qdoc/htmlgenerator.cpp
+++ b/src/qdoc/htmlgenerator.cpp
@@ -39,6 +39,7 @@
 #include "examplenode.h"
 #include "functionnode.h"
 #include "helpprojectwriter.h"
+#include "manifestwriter.h"
 #include "node.h"
 #include "propertynode.h"
 #include "qdocdatabase.h"
@@ -79,7 +80,7 @@ static void addLink(const QString &linkTarget, QStringView nestedStuff, QString
 
 /*!
   Destroys the HTML output generator. Deletes the singleton
-  instance of HelpProjectWriter.
+  instance of HelpProjectWriter and the ManifestWriter instance.
  */
 HtmlGenerator::~HtmlGenerator()
 {
@@ -87,6 +88,11 @@ HtmlGenerator::~HtmlGenerator()
         delete m_helpProjectWriter;
         m_helpProjectWriter = nullptr;
     }
+
+    if (m_manifestWriter) {
+        delete m_manifestWriter;
+        m_manifestWriter = nullptr;
+    }
 }
 
 /*!
@@ -172,21 +178,14 @@ void HtmlGenerator::initializeGenerator()
     else
         m_helpProjectWriter = new HelpProjectWriter(m_project.toLower() + ".qhp", this);
 
+    if (!m_manifestWriter)
+        m_manifestWriter = new ManifestWriter();
+
     // Documentation template handling
     m_headerScripts =
             config->getString(HtmlGenerator::format() + Config::dot + CONFIG_HEADERSCRIPTS);
     m_headerStyles = config->getString(HtmlGenerator::format() + Config::dot + CONFIG_HEADERSTYLES);
 
-    QString prefix = CONFIG_QHP + Config::dot + m_project + Config::dot;
-    m_manifestDir =
-            QLatin1String("qthelp://") + config->getString(prefix + QLatin1String("namespace"));
-    m_manifestDir += QLatin1Char('/') + config->getString(prefix + QLatin1String("virtualFolder"))
-            + QLatin1Char('/');
-    readManifestMetaContent();
-    m_examplesPath = config->getString(CONFIG_EXAMPLESINSTALLPATH);
-    if (!m_examplesPath.isEmpty())
-        m_examplesPath += QLatin1Char('/');
-
     // Retrieve the config for the navigation bar
     m_homepage = config->getString(CONFIG_NAVIGATION + Config::dot + CONFIG_HOMEPAGE);
 
@@ -259,7 +258,7 @@ void HtmlGenerator::generateDocs()
 
     if (!config->preparing()) {
         m_helpProjectWriter->generate();
-        generateManifestFiles();
+        m_manifestWriter->generateManifestFiles();
         /*
           Generate the XML tag file, if it was requested.
         */
@@ -3660,271 +3659,4 @@ void HtmlGenerator::generateExtractionMark(const Node *node, ExtractionMarkType
     }
 }
 
-/*!
-  This function outputs one or more manifest files in XML.
-  They are used by Creator.
- */
-void HtmlGenerator::generateManifestFiles()
-{
-    generateManifestFile("examples", "example");
-    generateManifestFile("demos", "demo");
-    m_qdb->exampleNodeMap().clear();
-    m_manifestMetaContent.clear();
-}
-
-/*!
-  Retrieve the install path for the \a example as specified with
-  the \meta command, or fall back to the one defined in .qdocconf.
- */
-QString HtmlGenerator::retrieveInstallPath(const ExampleNode *example)
-{
-    QString installPath;
-    if (example->doc().metaTagMap())
-        installPath = example->doc().metaTagMap()->value(QLatin1String("installpath"));
-    if (installPath.isEmpty())
-        installPath = m_examplesPath;
-    if (!installPath.isEmpty() && !installPath.endsWith(QLatin1Char('/')))
-        installPath += QLatin1Char('/');
-
-    return installPath;
-}
-
-/*!
-  This function is called by generateManifestFiles(), once
-  for each manifest file to be generated. \a manifest is the
-  type of manifest file.
- */
-void HtmlGenerator::generateManifestFile(const QString &manifest, const QString &element)
-{
-    ExampleNodeMap &exampleNodeMap = m_qdb->exampleNodeMap();
-    if (exampleNodeMap.isEmpty())
-        return;
-    QString fileName = manifest + "-manifest.xml";
-    QFile file(outputDir() + QLatin1Char('/') + fileName);
-    bool demos = false;
-    if (manifest == QLatin1String("demos"))
-        demos = true;
-
-    bool proceed = false;
-    for (auto map = exampleNodeMap.begin(); map != exampleNodeMap.end(); ++map) {
-        const ExampleNode *en = map.value();
-        if (demos == en->name().startsWith("demos")) {
-            proceed = true;
-            break;
-        }
-    }
-    if (!proceed || !file.open(QFile::WriteOnly | QFile::Text))
-        return;
-
-    QXmlStreamWriter writer(&file);
-    writer.setAutoFormatting(true);
-    writer.writeStartDocument();
-    writer.writeStartElement("instructionals");
-    writer.writeAttribute("module", m_project);
-    writer.writeStartElement(manifest);
-
-    QStringList usedAttributes;
-    for (auto map = exampleNodeMap.begin(); map != exampleNodeMap.end(); ++map) {
-        const ExampleNode *en = map.value();
-        if (demos) {
-            if (!en->name().startsWith("demos"))
-                continue;
-        } else if (en->name().startsWith("demos")) {
-            continue;
-        }
-
-        const QString installPath = retrieveInstallPath(en);
-        // attributes that are always written for the element
-        usedAttributes.clear();
-        usedAttributes << "name"
-                       << "docUrl"
-                       << "projectPath";
-
-        writer.writeStartElement(element);
-        writer.writeAttribute("name", en->title());
-        QString docUrl = m_manifestDir + appendObsoleteToFileBase(en) + ".html";
-        writer.writeAttribute("docUrl", docUrl);
-        const auto exampleFiles = en->files();
-        if (en->projectFile().isEmpty())
-            Location().warning("Example does not have a project file: ", en->name());
-        else
-            writer.writeAttribute("projectPath", installPath + en->projectFile());
-        if (en->imageFileName().isEmpty()) {
-            Location().warning("Example does not have an image file: ", en->name());
-        } else {
-            writer.writeAttribute("imageUrl", m_manifestDir + en->imageFileName());
-            usedAttributes << "imageUrl";
-        }
-
-        QString fullName = m_project + QLatin1Char('/') + en->title();
-        QSet<QString> tags;
-        for (const auto &index : m_manifestMetaContent) {
-            const auto &names = index.names;
-            for (const QString &name : names) {
-                bool match = false;
-                int wildcard = name.indexOf(QChar('*'));
-                switch (wildcard) {
-                case -1: // no wildcard, exact match
-                    match = (fullName == name);
-                    break;
-                case 0: // '*' matches all
-                    match = true;
-                    break;
-                default: // match with wildcard at the end
-                    match = fullName.startsWith(name.left(wildcard));
-                }
-                if (match) {
-                    tags += index.tags;
-                    const auto attributes = index.attributes;
-                    for (const QString &attr : attributes) {
-                        QLatin1Char div(':');
-                        QStringList attrList = attr.split(div);
-                        if (attrList.count() == 1)
-                            attrList.append(QStringLiteral("true"));
-                        QString attrName = attrList.takeFirst();
-                        if (!usedAttributes.contains(attrName)) {
-                            writer.writeAttribute(attrName, attrList.join(div));
-                            usedAttributes << attrName;
-                        }
-                    }
-                }
-            }
-        }
-
-        writer.writeStartElement("description");
-        Text brief = en->doc().briefText();
-        if (!brief.isEmpty())
-            writer.writeCDATA(brief.toString());
-        else
-            writer.writeCDATA(QString("No description available"));
-        writer.writeEndElement(); // description
-
-        // Add words from module name as tags
-        // QtQuickControls -> qt,quick,controls
-        // QtOpenGL -> qt,opengl
-        QRegularExpression re("([A-Z]+[a-z0-9]*(3D|GL)?)");
-        int pos = 0;
-        QRegularExpressionMatch match;
-        while ((match = re.match(m_project, pos)).hasMatch()) {
-            tags << match.captured(1).toLower();
-            pos = match.capturedEnd();
-        }
-
-        // Include tags added via \meta {tag} {tag1[,tag2,...]}
-        // within \example topic
-        QStringMultiMap *metaTagMap = en->doc().metaTagMap();
-        if (metaTagMap) {
-            for (const auto &tag : metaTagMap->values("tag")) {
-                const auto &tagList = tag.toLower().split(QLatin1Char(','));
-                tags += QSet<QString>(tagList.cbegin(), tagList.cend());
-            }
-        }
-
-        const auto &titleWords = en->title().toLower().split(QLatin1Char(' '));
-        tags += QSet<QString>(titleWords.cbegin(), titleWords.cend());
-
-        // Clean up tags, exclude invalid and common words
-        QSet<QString>::iterator tag_it = tags.begin();
-        QSet<QString> modified;
-        while (tag_it != tags.end()) {
-            QString s = *tag_it;
-            if (s.at(0) == '(')
-                s.remove(0, 1).chop(1);
-            if (s.endsWith(QLatin1Char(':')))
-                s.chop(1);
-
-            if (s.length() < 2 || s.at(0).isDigit() || s.at(0) == '-' || s == QLatin1String("qt")
-                || s == QLatin1String("the") || s == QLatin1String("and")
-                || s.startsWith(QLatin1String("example")) || s.startsWith(QLatin1String("chapter")))
-                tag_it = tags.erase(tag_it);
-            else if (s != *tag_it) {
-                modified << s;
-                tag_it = tags.erase(tag_it);
-            } else
-                ++tag_it;
-        }
-        tags += modified;
-
-        if (!tags.isEmpty()) {
-            writer.writeStartElement("tags");
-            bool wrote_one = false;
-            QStringList sortedTags = tags.values();
-            sortedTags.sort();
-            for (const auto &tag : qAsConst(sortedTags)) {
-                if (wrote_one)
-                    writer.writeCharacters(",");
-                writer.writeCharacters(tag);
-                wrote_one = true;
-            }
-            writer.writeEndElement(); // tags
-        }
-
-        QString ename = en->name().mid(en->name().lastIndexOf('/') + 1);
-        QMap<int, QString> filesToOpen;
-        const auto files = en->files();
-        for (const QString &file : files) {
-            QFileInfo fileInfo(file);
-            QString fileName = fileInfo.fileName().toLower();
-            // open .qml, .cpp and .h files with a
-            // basename matching the example (project) name
-            // QMap key indicates the priority -
-            // the lowest value will be the top-most file
-            if ((fileInfo.baseName().compare(ename, Qt::CaseInsensitive) == 0)) {
-                if (fileName.endsWith(".qml"))
-                    filesToOpen.insert(0, file);
-                else if (fileName.endsWith(".cpp"))
-                    filesToOpen.insert(1, file);
-                else if (fileName.endsWith(".h"))
-                    filesToOpen.insert(2, file);
-            }
-            // main.qml takes precedence over main.cpp
-            else if (fileName.endsWith("main.qml")) {
-                filesToOpen.insert(3, file);
-            } else if (fileName.endsWith("main.cpp")) {
-                filesToOpen.insert(4, file);
-            }
-        }
-
-        for (auto it = filesToOpen.constEnd(); it != filesToOpen.constBegin();) {
-            writer.writeStartElement("fileToOpen");
-            if (--it == filesToOpen.constBegin()) {
-                writer.writeAttribute(QStringLiteral("mainFile"), QStringLiteral("true"));
-            }
-            writer.writeCharacters(installPath + it.value());
-            writer.writeEndElement();
-        }
-
-        writer.writeEndElement(); // example
-    }
-
-    writer.writeEndElement(); // examples
-    writer.writeEndElement(); // instructionals
-    writer.writeEndDocument();
-    file.close();
-}
-
-/*!
-  Reads metacontent - additional attributes and tags to apply
-  when generating manifest files, read from config. Takes the
-  configuration class \a config as a parameter.
-
-  The manifest metacontent map is cleared immediately after
-  the manifest files have been generated.
- */
-void HtmlGenerator::readManifestMetaContent()
-{
-    Config &config = Config::instance();
-    const QStringList names =
-            config.getStringList(CONFIG_MANIFESTMETA + Config::dot + QStringLiteral("filters"));
-
-    for (const auto &manifest : names) {
-        ManifestMetaFilter filter;
-        QString prefix = CONFIG_MANIFESTMETA + Config::dot + manifest + Config::dot;
-        filter.names = config.getStringSet(prefix + QStringLiteral("names"));
-        filter.attributes = config.getStringSet(prefix + QStringLiteral("attributes"));
-        filter.tags = config.getStringSet(prefix + QStringLiteral("tags"));
-        m_manifestMetaContent.append(filter);
-    }
-}
-
 QT_END_NAMESPACE
diff --git a/src/qdoc/htmlgenerator.h b/src/qdoc/htmlgenerator.h
index 83a3248a7..07cc4c0d7 100644
--- a/src/qdoc/htmlgenerator.h
+++ b/src/qdoc/htmlgenerator.h
@@ -42,6 +42,7 @@ class Aggregate;
 class Config;
 class ExampleNode;
 class HelpProjectWriter;
+class ManifestWriter;
 
 class HtmlGenerator : public XmlGenerator
 {
@@ -53,7 +54,6 @@ public:
     void terminateGenerator() override;
     QString format() override;
     void generateDocs() override;
-    void generateManifestFiles();
 
     QString protectEnc(const QString &string);
     static QString protect(const QString &string);
@@ -69,9 +69,6 @@ protected:
     void generateCollectionNode(CollectionNode *cn, CodeMarker *marker) override;
     void generateGenericCollectionPage(CollectionNode *cn, CodeMarker *marker) override;
     QString fileExtension() const override;
-
-    void generateManifestFile(const QString &manifest, const QString &element);
-    void readManifestMetaContent();
     void generateKeywordAnchors(const Node *node);
 
 private:
@@ -85,7 +82,6 @@ private:
         QSet<QString> tags;
     };
 
-    QString retrieveInstallPath(const ExampleNode *exampleNode);
     void generateNavigationBar(const QString &title, const Node *node, CodeMarker *marker,
                                const QString &buildversion, bool tableItems = false);
     void generateHeader(const QString &title, const Node *node = nullptr,
@@ -164,6 +160,7 @@ private:
     QString m_codePrefix {};
     QString m_codeSuffix {};
     HelpProjectWriter *m_helpProjectWriter { nullptr };
+    ManifestWriter *m_manifestWriter { nullptr };
     bool m_inObsoleteLink { false };
     QRegularExpression m_funcLeftParen { "\\S(\\()" };
     QString m_headerScripts {};
diff --git a/src/qdoc/manifestwriter.cpp b/src/qdoc/manifestwriter.cpp
new file mode 100644
index 000000000..d19c6d6ff
--- /dev/null
+++ b/src/qdoc/manifestwriter.cpp
@@ -0,0 +1,328 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include "manifestwriter.h"
+
+#include "config.h"
+#include "examplenode.h"
+#include "generator.h"
+#include "qdocdatabase.h"
+
+#include <QtCore/qxmlstream.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class ManifestWriter
+    \internal
+    \brief The ManifestWriter is responsible for writing manifest files.
+ */
+ManifestWriter::ManifestWriter()
+{
+    Config &config = Config::instance();
+    m_project = config.getString(CONFIG_PROJECT);
+    m_outputDirectory = config.getOutputDir();
+    m_qdb = QDocDatabase::qdocDB();
+
+    const QString prefix = CONFIG_QHP + Config::dot + m_project + Config::dot;
+    m_manifestDir =
+            QLatin1String("qthelp://") + config.getString(prefix + QLatin1String("namespace"));
+    m_manifestDir += QLatin1Char('/') + config.getString(prefix + QLatin1String("virtualFolder"))
+            + QLatin1Char('/');
+    readManifestMetaContent();
+    m_examplesPath = config.getString(CONFIG_EXAMPLESINSTALLPATH);
+    if (!m_examplesPath.isEmpty())
+        m_examplesPath += QLatin1Char('/');
+}
+
+/*!
+  This function outputs one or more manifest files in XML.
+  They are used by Creator.
+ */
+void ManifestWriter::generateManifestFiles()
+{
+    generateManifestFile("examples", "example");
+    generateManifestFile("demos", "demo");
+    m_qdb->exampleNodeMap().clear();
+    m_manifestMetaContent.clear();
+}
+
+/*!
+  This function is called by generateManifestFiles(), once
+  for each manifest file to be generated. \a manifest is the
+  type of manifest file.
+ */
+void ManifestWriter::generateManifestFile(const QString &manifest, const QString &element)
+{
+    const ExampleNodeMap &exampleNodeMap = m_qdb->exampleNodeMap();
+    if (exampleNodeMap.isEmpty())
+        return;
+    const QString fileName = manifest + "-manifest.xml";
+    QFile file(m_outputDirectory + QLatin1Char('/') + fileName);
+    bool demos = false;
+    if (manifest == QLatin1String("demos"))
+        demos = true;
+
+    bool proceed = false;
+    for (auto map = exampleNodeMap.begin(); map != exampleNodeMap.end(); ++map) {
+        const ExampleNode *en = map.value();
+        if (demos == en->name().startsWith("demos")) {
+            proceed = true;
+            break;
+        }
+    }
+    if (!proceed || !file.open(QFile::WriteOnly | QFile::Text))
+        return;
+
+    QXmlStreamWriter writer(&file);
+    writer.setAutoFormatting(true);
+    writer.writeStartDocument();
+    writer.writeStartElement("instructionals");
+    writer.writeAttribute("module", m_project);
+    writer.writeStartElement(manifest);
+
+    QStringList usedAttributes;
+    for (auto map = exampleNodeMap.begin(); map != exampleNodeMap.end(); ++map) {
+        const ExampleNode *en = map.value();
+        if (demos) {
+            if (!en->name().startsWith("demos"))
+                continue;
+        } else if (en->name().startsWith("demos")) {
+            continue;
+        }
+
+        const QString installPath = retrieveInstallPath(en);
+        // attributes that are always written for the element
+        usedAttributes.clear();
+        usedAttributes << "name"
+                       << "docUrl"
+                       << "projectPath";
+
+        writer.writeStartElement(element);
+        writer.writeAttribute("name", en->title());
+        QString docUrl = m_manifestDir + Generator::fileBase(en) + ".html";
+        writer.writeAttribute("docUrl", docUrl);
+        const auto exampleFiles = en->files();
+        if (en->projectFile().isEmpty())
+            Location().warning("Example does not have a project file: ", en->name());
+        else
+            writer.writeAttribute("projectPath", installPath + en->projectFile());
+        if (en->imageFileName().isEmpty()) {
+            Location().warning("Example does not have an image file: ", en->name());
+        } else {
+            writer.writeAttribute("imageUrl", m_manifestDir + en->imageFileName());
+            usedAttributes << "imageUrl";
+        }
+
+        QString fullName = m_project + QLatin1Char('/') + en->title();
+        QSet<QString> tags;
+        for (const auto &index : m_manifestMetaContent) {
+            const auto &names = index.names;
+            for (const QString &name : names) {
+                bool match;
+                int wildcard = name.indexOf(QChar('*'));
+                switch (wildcard) {
+                case -1: // no wildcard, exact match
+                    match = (fullName == name);
+                    break;
+                case 0: // '*' matches all
+                    match = true;
+                    break;
+                default: // match with wildcard at the end
+                    match = fullName.startsWith(name.left(wildcard));
+                }
+                if (match) {
+                    tags += index.tags;
+                    const auto attributes = index.attributes;
+                    for (const QString &attr : attributes) {
+                        QLatin1Char div(':');
+                        QStringList attrList = attr.split(div);
+                        if (attrList.count() == 1)
+                            attrList.append(QStringLiteral("true"));
+                        QString attrName = attrList.takeFirst();
+                        if (!usedAttributes.contains(attrName)) {
+                            writer.writeAttribute(attrName, attrList.join(div));
+                            usedAttributes << attrName;
+                        }
+                    }
+                }
+            }
+        }
+
+        writer.writeStartElement("description");
+        Text brief = en->doc().briefText();
+        if (!brief.isEmpty())
+            writer.writeCDATA(brief.toString());
+        else
+            writer.writeCDATA(QString("No description available"));
+        writer.writeEndElement(); // description
+
+        // Add words from module name as tags
+        // QtQuickControls -> qt,quick,controls
+        // QtOpenGL -> qt,opengl
+        QRegularExpression re("([A-Z]+[a-z0-9]*(3D|GL)?)");
+        int pos = 0;
+        QRegularExpressionMatch match;
+        while ((match = re.match(m_project, pos)).hasMatch()) {
+            tags << match.captured(1).toLower();
+            pos = match.capturedEnd();
+        }
+
+        // Include tags added via \meta {tag} {tag1[,tag2,...]}
+        // within \example topic
+        const QStringMultiMap *metaTagMap = en->doc().metaTagMap();
+        if (metaTagMap) {
+            for (const auto &tag : metaTagMap->values("tag")) {
+                const auto &tagList = tag.toLower().split(QLatin1Char(','));
+                tags += QSet<QString>(tagList.cbegin(), tagList.cend());
+            }
+        }
+
+        const auto &titleWords = en->title().toLower().split(QLatin1Char(' '));
+        tags += QSet<QString>(titleWords.cbegin(), titleWords.cend());
+
+        // Clean up tags, exclude invalid and common words
+        QSet<QString>::iterator tag_it = tags.begin();
+        QSet<QString> modified;
+        while (tag_it != tags.end()) {
+            QString s = *tag_it;
+            if (s.at(0) == '(')
+                s.remove(0, 1).chop(1);
+            if (s.endsWith(QLatin1Char(':')))
+                s.chop(1);
+
+            if (s.length() < 2 || s.at(0).isDigit() || s.at(0) == '-' || s == QLatin1String("qt")
+                || s == QLatin1String("the") || s == QLatin1String("and")
+                || s.startsWith(QLatin1String("example")) || s.startsWith(QLatin1String("chapter")))
+                tag_it = tags.erase(tag_it);
+            else if (s != *tag_it) {
+                modified << s;
+                tag_it = tags.erase(tag_it);
+            } else
+                ++tag_it;
+        }
+        tags += modified;
+
+        if (!tags.isEmpty()) {
+            writer.writeStartElement("tags");
+            bool wrote_one = false;
+            QStringList sortedTags = tags.values();
+            sortedTags.sort();
+            for (const auto &tag : qAsConst(sortedTags)) {
+                if (wrote_one)
+                    writer.writeCharacters(",");
+                writer.writeCharacters(tag);
+                wrote_one = true;
+            }
+            writer.writeEndElement(); // tags
+        }
+
+        QString exampleName = en->name().mid(en->name().lastIndexOf('/') + 1);
+        QMap<int, QString> filesToOpen;
+        const auto files = en->files();
+        for (const QString &file : files) {
+            QFileInfo fileInfo(file);
+            QString fileName = fileInfo.fileName().toLower();
+            // open .qml, .cpp and .h files with a
+            // basename matching the example (project) name
+            // QMap key indicates the priority -
+            // the lowest value will be the top-most file
+            if ((fileInfo.baseName().compare(exampleName, Qt::CaseInsensitive) == 0)) {
+                if (fileName.endsWith(".qml"))
+                    filesToOpen.insert(0, file);
+                else if (fileName.endsWith(".cpp"))
+                    filesToOpen.insert(1, file);
+                else if (fileName.endsWith(".h"))
+                    filesToOpen.insert(2, file);
+            }
+            // main.qml takes precedence over main.cpp
+            else if (fileName.endsWith("main.qml")) {
+                filesToOpen.insert(3, file);
+            } else if (fileName.endsWith("main.cpp")) {
+                filesToOpen.insert(4, file);
+            }
+        }
+
+        for (auto it = filesToOpen.constEnd(); it != filesToOpen.constBegin();) {
+            writer.writeStartElement("fileToOpen");
+            if (--it == filesToOpen.constBegin()) {
+                writer.writeAttribute(QStringLiteral("mainFile"), QStringLiteral("true"));
+            }
+            writer.writeCharacters(installPath + it.value());
+            writer.writeEndElement();
+        }
+
+        writer.writeEndElement(); // example
+    }
+
+    writer.writeEndElement(); // examples
+    writer.writeEndElement(); // instructionals
+    writer.writeEndDocument();
+    file.close();
+}
+
+/*!
+  Reads metacontent - additional attributes and tags to apply
+  when generating manifest files, read from config.
+
+  The manifest metacontent map is cleared immediately after
+  the manifest files have been generated.
+ */
+void ManifestWriter::readManifestMetaContent()
+{
+    Config &config = Config::instance();
+    const QStringList names =
+            config.getStringList(CONFIG_MANIFESTMETA + Config::dot + QStringLiteral("filters"));
+
+    for (const auto &manifest : names) {
+        ManifestMetaFilter filter;
+        QString prefix = CONFIG_MANIFESTMETA + Config::dot + manifest + Config::dot;
+        filter.names = config.getStringSet(prefix + QStringLiteral("names"));
+        filter.attributes = config.getStringSet(prefix + QStringLiteral("attributes"));
+        filter.tags = config.getStringSet(prefix + QStringLiteral("tags"));
+        m_manifestMetaContent.append(filter);
+    }
+}
+
+/*!
+  Retrieve the install path for the \a example as specified with
+  the \meta command, or fall back to the one defined in .qdocconf.
+ */
+QString ManifestWriter::retrieveInstallPath(const ExampleNode *example)
+{
+    QString installPath;
+    if (example->doc().metaTagMap())
+        installPath = example->doc().metaTagMap()->value(QLatin1String("installpath"));
+    if (installPath.isEmpty())
+        installPath = m_examplesPath;
+    if (!installPath.isEmpty() && !installPath.endsWith(QLatin1Char('/')))
+        installPath += QLatin1Char('/');
+
+    return installPath;
+}
+
+QT_END_NAMESPACE
diff --git a/src/qdoc/manifestwriter.h b/src/qdoc/manifestwriter.h
new file mode 100644
index 000000000..907a7742c
--- /dev/null
+++ b/src/qdoc/manifestwriter.h
@@ -0,0 +1,67 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the tools applications of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#ifndef MANIFESTWRITER_H
+#define MANIFESTWRITER_H
+
+#include <QtCore/qlist.h>
+#include <QtCore/qset.h>
+#include <QtCore/qstring.h>
+
+QT_BEGIN_NAMESPACE
+
+class ExampleNode;
+class QDocDatabase;
+
+class ManifestWriter
+{
+    struct ManifestMetaFilter
+    {
+        QSet<QString> names;
+        QSet<QString> attributes;
+        QSet<QString> tags;
+    };
+
+public:
+    ManifestWriter();
+    void generateManifestFiles();
+    void generateManifestFile(const QString &manifest, const QString &element);
+    void readManifestMetaContent();
+    QString retrieveInstallPath(const ExampleNode *example);
+
+private:
+    QString m_manifestDir {};
+    QString m_examplesPath {};
+    QString m_outputDirectory {};
+    QString m_project {};
+    QDocDatabase *m_qdb { nullptr };
+    QList<ManifestMetaFilter> m_manifestMetaContent {};
+};
+
+QT_END_NAMESPACE
+
+#endif // MANIFESTWRITER_H
diff --git a/src/qdoc/qdoc.pro b/src/qdoc/qdoc.pro
index a1f47300d..a6a31eb77 100644
--- a/src/qdoc/qdoc.pro
+++ b/src/qdoc/qdoc.pro
@@ -62,6 +62,7 @@ HEADERS += access.h \
            location.h \
            loggingcategory.h \
            macro.h \
+           manifestwriter.h \
            namespacenode.h \
            node.h \
            openedlist.h \
@@ -118,6 +119,7 @@ SOURCES += aggregate.cpp \
            htmlgenerator.cpp \
            location.cpp \
            main.cpp \
+           manifestwriter.cpp \
            namespacenode.cpp \
            node.cpp \
            openedlist.cpp \