From 601eebd832e8f8a39d661031a44d5ee3c53bf718 Mon Sep 17 00:00:00 2001
From: Eike Ziller <eike.ziller@qt.io>
Date: Thu, 23 Aug 2018 11:32:12 +0200
Subject: [PATCH] Fix painting of current line in generic and python editors

The generic highlighter and the python editor explicitly map some tokens
to the format C_TEXT. Unfortunately this format is special, because it's
foreground and background colors are handled by setting the editor's
palette, and should not be used for setting the format on characters.

If the format is explicitly set on characters, their background will be
oblique and overpaint e.g. the highlight for the current line, which
looks pretty ugly.

Handle this directly in SyntaxHighlighter::formatForCategory for all
syntax highlighters, by returning an empty QTextCharFormat for C_TEXT.

Change-Id: Ifaeb556754ca8106ad6e55d7062b13b45457a809
Reviewed-by: David Schulz <david.schulz@qt.io>
---
 .../texteditor/generichighlighter/highlighter.cpp    | 12 +++++++-----
 src/plugins/texteditor/syntaxhighlighter.cpp         |  8 ++++++--
 .../highlighterengine/highlighterengine.pro          |  2 +-
 .../highlighterengine/highlighterengine.qbs          |  1 +
 4 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/src/plugins/texteditor/generichighlighter/highlighter.cpp b/src/plugins/texteditor/generichighlighter/highlighter.cpp
index e7e5e713ab4..8ece3f462ed 100644
--- a/src/plugins/texteditor/generichighlighter/highlighter.cpp
+++ b/src/plugins/texteditor/generichighlighter/highlighter.cpp
@@ -23,17 +23,19 @@
 **
 ****************************************************************************/
 
-#include "highlighter.h"
-#include "highlightdefinition.h"
 #include "context.h"
-#include "rule.h"
-#include "itemdata.h"
+#include "highlightdefinition.h"
+#include "highlighter.h"
 #include "highlighterexception.h"
+#include "itemdata.h"
 #include "progressdata.h"
 #include "reuse.h"
+#include "rule.h"
 #include "tabsettings.h"
 
 #include <coreplugin/messagemanager.h>
+#include <texteditor/fontsettings.h>
+#include <texteditor/texteditorsettings.h>
 #include <utils/qtcassert.h>
 
 #include <QCoreApplication>
@@ -567,7 +569,7 @@ void Highlighter::applyFormat(int offset,
             // think this approach would fit better. If there are other ideas...
             QBrush bg = format.background();
             if (bg.style() == Qt::NoBrush)
-                bg = formatForCategory(C_TEXT).background();
+                bg = TextEditorSettings::fontSettings().toTextCharFormat(C_TEXT).background();
             if (itemData->color().isValid() && isReadableOn(bg.color(), itemData->color()))
                 format.setForeground(itemData->color());
             if (itemData->isItalicSpecified())
diff --git a/src/plugins/texteditor/syntaxhighlighter.cpp b/src/plugins/texteditor/syntaxhighlighter.cpp
index f72b563ca55..621df4f236d 100644
--- a/src/plugins/texteditor/syntaxhighlighter.cpp
+++ b/src/plugins/texteditor/syntaxhighlighter.cpp
@@ -836,8 +836,12 @@ void SyntaxHighlighter::highlightBlock(const QString &text)
 
 void SyntaxHighlighterPrivate::updateFormats(const FontSettings &fontSettings)
 {
-    for (const auto &pair : qAsConst(formatCategories))
-        formats[pair.first] = fontSettings.toTextCharFormat(pair.second);
+    // C_TEXT is handled by text editor's foreground and background color,
+    // so use empty format for that
+    for (const auto &pair : qAsConst(formatCategories)) {
+        formats[pair.first] = pair.second == C_TEXT ? QTextCharFormat()
+                                                    : fontSettings.toTextCharFormat(pair.second);
+    }
     whitespaceFormat = fontSettings.toTextCharFormat(C_VISUAL_WHITESPACE);
 }
 
diff --git a/tests/auto/generichighlighter/highlighterengine/highlighterengine.pro b/tests/auto/generichighlighter/highlighterengine/highlighterengine.pro
index 3270181891e..d78de7871eb 100644
--- a/tests/auto/generichighlighter/highlighterengine/highlighterengine.pro
+++ b/tests/auto/generichighlighter/highlighterengine/highlighterengine.pro
@@ -1,4 +1,4 @@
-QTC_PLUGIN_DEPENDS += coreplugin
+QTC_PLUGIN_DEPENDS += coreplugin texteditor
 include(../../qttest.pri)
 QT += gui
 PLUGINSDIR = $$IDE_SOURCE_TREE/src/plugins
diff --git a/tests/auto/generichighlighter/highlighterengine/highlighterengine.qbs b/tests/auto/generichighlighter/highlighterengine/highlighterengine.qbs
index 3ea2c0da683..b0abba77760 100644
--- a/tests/auto/generichighlighter/highlighterengine/highlighterengine.qbs
+++ b/tests/auto/generichighlighter/highlighterengine/highlighterengine.qbs
@@ -4,6 +4,7 @@ QtcAutotest {
     name: "Highlighter engine autotest"
     Depends { name: "Core" }
     Depends { name: "Utils" }
+    Depends { name: "TextEditor" }
     Depends { name: "Qt.widgets" }
     Group {
         name: "Sources from TextEditor plugin"