SyntaxHighlighter: Remove using global fontSettings

Currently, default font settings are set inside the highlighter
runner after creating a highlighter. It prevents to call
TextEditorSettings::fontSettings() from non-main threads.

Change-Id: I0c806f0f586c67749cb2964bebdf2bf3c58a5302
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/haskell/haskellhighlighter.cpp

@@ -26,7 +26,6 @@ namespace Internal {
 HaskellHighlighter::HaskellHighlighter()
 {
     setDefaultTextFormatCategories();
-    updateFormats(TextEditorSettings::fontSettings());
 }
 
 void HaskellHighlighter::highlightBlock(const QString &text)

src/plugins/texteditor/syntaxhighlighter.cpp

@@ -27,9 +27,7 @@ class SyntaxHighlighterPrivate
     SyntaxHighlighter *q_ptr = nullptr;
     Q_DECLARE_PUBLIC(SyntaxHighlighter)
 public:
-    SyntaxHighlighterPrivate()
-        : SyntaxHighlighterPrivate(TextEditorSettings::fontSettings())
-    { }
+    SyntaxHighlighterPrivate() = default;
 
     SyntaxHighlighterPrivate(const FontSettings &fontSettings)
     {
@@ -881,7 +879,7 @@ void SyntaxHighlighter::setTextFormatCategories(const QList<std::pair<int, TextS
     d->formatCategories = categories;
     const int maxCategory = Utils::maxElementOr(categories, {-1, C_TEXT}).first;
     d->formats = QList<QTextCharFormat>(maxCategory + 1);
-    d->updateFormats(TextEditorSettings::fontSettings());
+    d->updateFormats(d->fontSettings);
 }
 
 QTextCharFormat SyntaxHighlighter::formatForCategory(int category) const
@@ -925,4 +923,3 @@ void SyntaxHighlighterPrivate::updateFormats(const FontSettings &fontSettings)
 }
 
 } // namespace TextEditor
-

src/plugins/texteditor/syntaxhighlighterrunner.cpp

@@ -5,6 +5,7 @@
 
 #include "fontsettings.h"
 #include "textdocumentlayout.h"
+#include "texteditorsettings.h"
 
 #include <utils/textutils.h>
 
@@ -19,13 +20,20 @@ class SyntaxHighlighterRunnerPrivate : public QObject
 {
     Q_OBJECT
 public:
+    void createHighlighter()
+    {
+        m_highlighter.reset(m_creator());
+        m_highlighter->setFontSettings(m_fontSettings);
+        m_highlighter->setDocument(m_document);
+    }
+
     SyntaxHighlighterRunnerPrivate(BaseSyntaxHighlighterRunner::SyntaxHighLighterCreator creator,
                                    QTextDocument *document)
         : m_creator(creator)
+        , m_document(document)
     {
         m_highlighter.reset(m_creator());
-        m_highlighter->setDocument(document);
-        m_document = document;
+        createHighlighter();
     }
 
     void create()
@@ -36,8 +44,7 @@ public:
         m_document = new QTextDocument(this);
         m_document->setDocumentLayout(new TextDocumentLayout(m_document));
 
-        m_highlighter.reset(m_creator());
-        m_highlighter->setDocument(m_document);
+        createHighlighter();
 
         connect(m_highlighter.get(),
                 &SyntaxHighlighter::resultsReady,
@@ -102,6 +109,7 @@ private:
     BaseSyntaxHighlighterRunner::SyntaxHighLighterCreator m_creator;
     std::unique_ptr<SyntaxHighlighter> m_highlighter;
     QTextDocument *m_document = nullptr;
+    const FontSettings m_fontSettings = TextEditorSettings::fontSettings();
 };
 
 // ----------------------------- BaseSyntaxHighlighterRunner --------------------------------------