Texteditor: Add ability to get margin from indenter

And implement it in the clang-format plugin to use the ColumnLimit from
the style. This would be quite useful if you're working on different
projects with a different ColumnLimit. This way you get an visual
representation and do not only have to rely on clang-format.

Change-Id: Ib0258e3fba6f45f0f46ce612f806527a47868ad9
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/clangformat/clangformatbaseindenter.cpp

@@ -679,6 +679,11 @@ bool ClangFormatBaseIndenter::isElectricCharacter(const QChar &ch) const
     return false;
 }
 
+std::optional<int> ClangFormat::ClangFormatBaseIndenter::margin() const
+{
+    return styleForFile().ColumnLimit;
+}
+
 void ClangFormatBaseIndenter::autoIndent(const QTextCursor &cursor,
                                          const TextEditor::TabSettings & /*tabSettings*/,
                                          int cursorPositionInEditor)

src/plugins/clangformat/clangformatbaseindenter.h

@@ -66,6 +66,8 @@ public:
 
     bool isElectricCharacter(const QChar &ch) const override;
 
+    std::optional<int> margin() const override;
+
 protected:
     virtual clang::format::FormatStyle styleForFile() const;
     virtual bool formatCodeInsteadOfIndent() const { return false; }

src/plugins/projectexplorer/editorconfiguration.cpp

@@ -372,6 +372,14 @@ void EditorConfiguration::setShowWrapColumn(bool onoff)
     }
 }
 
+void EditorConfiguration::setUseIndenter(bool onoff)
+{
+    if (d->m_marginSettings.m_useIndenter != onoff) {
+        d->m_marginSettings.m_useIndenter = onoff;
+        emit marginSettingsChanged(d->m_marginSettings);
+    }
+}
+
 void EditorConfiguration::setWrapColumn(int column)
 {
     if (d->m_marginSettings.m_marginColumn != column) {

src/plugins/projectexplorer/editorconfiguration.h

@@ -94,6 +94,7 @@ public:
     void setMarginSettings(const TextEditor::MarginSettings &settings);
 
     void setShowWrapColumn(bool onoff);
+    void setUseIndenter(bool onoff);
     void setWrapColumn(int column);
 
     void setTextCodec(QTextCodec *textCodec);

src/plugins/projectexplorer/editorsettingspropertiespage.cpp

@@ -55,6 +55,8 @@ EditorSettingsWidget::EditorSettingsWidget(Project *project) : QWidget(), m_proj
 
     connect(m_ui.showWrapColumn, &QAbstractButton::toggled,
             config, &EditorConfiguration::setShowWrapColumn);
+    connect(m_ui.useIndenter, &QAbstractButton::toggled,
+            config, &EditorConfiguration::setUseIndenter);
     connect(m_ui.wrapColumn, QOverload<int>::of(&QSpinBox::valueChanged),
             config, &EditorConfiguration::setWrapColumn);
 
@@ -73,6 +75,7 @@ EditorSettingsWidget::EditorSettingsWidget(Project *project) : QWidget(), m_proj
 void EditorSettingsWidget::settingsToUi(const EditorConfiguration *config)
 {
     m_ui.showWrapColumn->setChecked(config->marginSettings().m_showMargin);
+    m_ui.useIndenter->setChecked(config->marginSettings().m_useIndenter);
     m_ui.wrapColumn->setValue(config->marginSettings().m_marginColumn);
     m_ui.behaviorSettingsWidget->setCodeStyle(config->codeStyle());
     m_ui.globalSelector->setCurrentIndex(config->useGlobalSettings() ? 0 : 1);

src/plugins/projectexplorer/editorsettingspropertiespage.ui

@@ -81,6 +81,16 @@
         </property>
        </widget>
       </item>
+      <item>
+       <widget class="QCheckBox" name="useIndenter">
+        <property name="toolTip">
+         <string>If available, use a different margin. For example, the ColumnLimit from the clang-format plugin.</string>
+        </property>
+        <property name="text">
+         <string>Use context specific margin</string>
+        </property>
+       </widget>
+      </item>
       <item>
        <spacer name="horizontalSpacer_2">
         <property name="orientation">

src/plugins/texteditor/displaysettingspage.cpp

@@ -89,6 +89,7 @@ void DisplaySettingsWidget::settingsFromUI(DisplaySettings &displaySettings,
     displaySettings.m_displayLineNumbers = m_ui.displayLineNumbers->isChecked();
     displaySettings.m_textWrapping = m_ui.enableTextWrapping->isChecked();
     marginSettings.m_showMargin = m_ui.showWrapColumn->isChecked();
+    marginSettings.m_useIndenter = m_ui.useIndenter->isChecked();
     marginSettings.m_marginColumn = m_ui.wrapColumn->value();
     displaySettings.m_visualizeWhitespace = m_ui.visualizeWhitespace->isChecked();
     displaySettings.m_displayFoldingMarkers = m_ui.displayFoldingMarkers->isChecked();
@@ -121,6 +122,7 @@ void DisplaySettingsWidget::settingsToUI()
     m_ui.displayLineNumbers->setChecked(displaySettings.m_displayLineNumbers);
     m_ui.enableTextWrapping->setChecked(displaySettings.m_textWrapping);
     m_ui.showWrapColumn->setChecked(marginSettings.m_showMargin);
+    m_ui.useIndenter->setChecked(marginSettings.m_useIndenter);
     m_ui.wrapColumn->setValue(marginSettings.m_marginColumn);
     m_ui.visualizeWhitespace->setChecked(displaySettings.m_visualizeWhitespace);
     m_ui.displayFoldingMarkers->setChecked(displaySettings.m_displayFoldingMarkers);

src/plugins/texteditor/displaysettingspage.ui

@@ -56,6 +56,16 @@
           </property>
          </widget>
         </item>
+        <item>
+         <widget class="QCheckBox" name="useIndenter">
+          <property name="toolTip">
+           <string>If available, use a different margin. For example, the ColumnLimit from the clang-format plugin.</string>
+          </property>
+          <property name="text">
+           <string>Use context specific margin</string>
+          </property>
+         </widget>
+        </item>
         <item>
          <spacer name="horizontalSpacer">
           <property name="orientation">

src/plugins/texteditor/indenter.h

@@ -120,6 +120,8 @@ public:
                           int cursorPositionInEditor = -1)
         = 0;
 
+    virtual std::optional<int> margin() const { return std::nullopt; }
+
 protected:
     QTextDocument *m_doc;
     Utils::FilePath m_fileName;

src/plugins/texteditor/marginsettings.cpp

@@ -32,11 +32,13 @@
 static const char showWrapColumnKey[] = "ShowMargin";
 static const char wrapColumnKey[] = "MarginColumn";
 static const char groupPostfix[] = "MarginSettings";
+static const char useIndenterColumnKey[] = "UseIndenter";
 
 using namespace TextEditor;
 
 MarginSettings::MarginSettings()
     : m_showMargin(false)
+    , m_useIndenter(false)
     , m_marginColumn(80)
 {
 }
@@ -48,6 +50,7 @@ void MarginSettings::toSettings(const QString &category, QSettings *s) const
         group.insert(0, category);
     s->beginGroup(group);
     s->setValue(QLatin1String(showWrapColumnKey), m_showMargin);
+    s->setValue(QLatin1String(useIndenterColumnKey), m_useIndenter);
     s->setValue(QLatin1String(wrapColumnKey), m_marginColumn);
     s->endGroup();
 }
@@ -62,24 +65,28 @@ void MarginSettings::fromSettings(const QString &category, const QSettings *s)
     *this = MarginSettings(); // Assign defaults
 
     m_showMargin = s->value(group + QLatin1String(showWrapColumnKey), m_showMargin).toBool();
+    m_useIndenter = s->value(group + QLatin1String(useIndenterColumnKey), m_useIndenter).toBool();
     m_marginColumn = s->value(group + QLatin1String(wrapColumnKey), m_marginColumn).toInt();
 }
 
 void MarginSettings::toMap(const QString &prefix, QVariantMap *map) const
 {
     map->insert(prefix + QLatin1String(showWrapColumnKey), m_showMargin);
+    map->insert(prefix + QLatin1String(useIndenterColumnKey), m_useIndenter);
     map->insert(prefix + QLatin1String(wrapColumnKey), m_marginColumn);
 }
 
 void MarginSettings::fromMap(const QString &prefix, const QVariantMap &map)
 {
     m_showMargin = map.value(prefix + QLatin1String(showWrapColumnKey), m_showMargin).toBool();
+    m_useIndenter = map.value(prefix + QLatin1String(useIndenterColumnKey), m_useIndenter).toBool();
     m_marginColumn = map.value(prefix + QLatin1String(wrapColumnKey), m_marginColumn).toInt();
 }
 
 bool MarginSettings::equals(const MarginSettings &other) const
 {
     return m_showMargin == other.m_showMargin
+        && m_useIndenter == other.m_useIndenter
         && m_marginColumn == other.m_marginColumn
         ;
 }

src/plugins/texteditor/marginsettings.h

@@ -49,6 +49,7 @@ public:
     bool equals(const MarginSettings &other) const;
 
     bool m_showMargin;
+    bool m_useIndenter;
     int m_marginColumn;
 };
 

src/plugins/texteditor/texteditor.cpp

@@ -1478,6 +1478,7 @@ void TextEditorWidget::openFinishedSuccessfully()
     moveCursor(QTextCursor::Start);
     d->updateCannotDecodeInfo();
     updateTextCodecLabel();
+    updateVisualWrapColumn();
 }
 
 TextDocumentPtr TextEditorWidget::textDocumentPtr() const
@@ -7438,8 +7439,8 @@ void TextEditorWidget::setDisplaySettings(const DisplaySettings &ds)
 
 void TextEditorWidget::setMarginSettings(const MarginSettings &ms)
 {
-    setVisibleWrapColumn(ms.m_showMargin ? ms.m_marginColumn : 0);
     d->m_marginSettings = ms;
+    updateVisualWrapColumn();
 
     viewport()->update();
     extraArea()->update();
@@ -8261,6 +8262,24 @@ bool TextEditorWidget::inFindScope(int selectionStart, int selectionEnd)
     return true;
 }
 
+void TextEditorWidget::updateVisualWrapColumn()
+{
+    auto calcMargin = [this]() {
+        const auto &ms = d->m_marginSettings;
+
+        if (!ms.m_showMargin) {
+            return 0;
+        }
+        if (ms.m_useIndenter) {
+            if (auto margin = d->m_document->indenter()->margin()) {
+                return *margin;
+            }
+        }
+        return ms.m_marginColumn;
+    };
+    setVisibleWrapColumn(calcMargin());
+}
+
 void TextEditorWidget::setBlockSelection(bool on)
 {
     if (d->m_inBlockSelectionMode == on)

src/plugins/texteditor/texteditor.h

@@ -621,6 +621,8 @@ private:
     friend class Internal::TextEditorWidgetPrivate;
     friend class Internal::TextEditorOverlay;
     friend class RefactorOverlay;
+
+    void updateVisualWrapColumn();
 };
 
 class TEXTEDITOR_EXPORT TextEditorLinkLabel : public Utils::ElidingLabel