ANSI: Add 256-color escape sequences support

Task-number: QTCREATORBUG-12623
Change-Id: If2f3168a77b366aae570b48f5070e85087fe76a6
Reviewed-by: André Hartmann <aha_1980@gmx.de>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/libs/utils/ansiescapecodehandler.cpp

@@ -168,9 +168,11 @@ QList<FormattedText> AnsiEscapeCodeHandler::parseText(const FormattedText &input
                         break;
                     case RgbTextColor:
                     case RgbBackgroundColor:
+                        // See http://en.wikipedia.org/wiki/ANSI_escape_code#Colors
                         if (++i >= numbers.size())
                             break;
-                        if (numbers.at(i).toInt() == 2) {
+                        switch (numbers.at(i).toInt()) {
+                        case 2:
                             // RGB set with format: 38;2;<r>;<g>;<b>
                             if ((i + 3) < numbers.size()) {
                                 (code == RgbTextColor) ?
@@ -183,10 +185,36 @@ QList<FormattedText> AnsiEscapeCodeHandler::parseText(const FormattedText &input
                                 setFormatScope(charFormat);
                             }
                             i += 3;
-                        } else if (numbers.at(i).toInt() == 5) {
+                            break;
-                            // rgb set with format: 38;5;<i>
+                        case 5:
-                            // unsupported because of unclear documentation, so we just skip <i>
+                            // 256 color mode with format: 38;5;<i>
+                            uint index = numbers.at(i + 1).toInt();
+
+                            QColor color;
+                            if (index < 8) {
+                                // The first 8 colors are standard low-intensity ANSI colors.
+                                color = ansiColor(index);
+                            } else if (index < 16) {
+                                // The next 8 colors are standard high-intensity ANSI colors.
+                                color = ansiColor(index - 8).lighter(150);
+                            } else if (index < 232) {
+                                // The next 216 colors are a 6x6x6 RGB cube.
+                                uint o = index - 16;
+                                color = QColor((o / 36) * 51, ((o / 6) % 6) * 51, (o % 6) * 51);
+                            } else {
+                                // The last 24 colors are a greyscale gradient.
+                                uint grey = (index - 232) * 11;
+                                color = QColor(grey, grey, grey);
+                            }
+
+                            if (code == RgbTextColor)
+                                charFormat.setForeground(color);
+                            else
+                                charFormat.setBackground(color);
+
+                            setFormatScope(charFormat);
                             ++i;
+                            break;
                         }
                         break;
                     default:

tests/auto/utils/ansiescapecodehandler/tst_ansiescapecodehandler.cpp

@@ -59,6 +59,7 @@ private Q_SLOTS:
 
 private:
     const QString red;
+    const QString mustard;
     const QString bold;
     const QString normal;
     const QString normal1;
@@ -66,6 +67,7 @@ private:
 
 tst_AnsiEscapeCodeHandler::tst_AnsiEscapeCodeHandler() :
     red(ansiEscape("31m")),
+    mustard(ansiEscape("38;5;220m")),
     bold(ansiEscape("1m")),
     normal(ansiEscape("0m")),
     normal1(ansiEscape("m"))
@@ -110,6 +112,18 @@ void tst_AnsiEscapeCodeHandler::testSimpleFormat_data()
                             << FormattedText("red", redFormat)
                             << FormattedText(" text", defaultFormat));
 
+    // Test 256-color text-color change
+    {
+        QTextCharFormat mustardFormat;
+        mustardFormat.setForeground(QColor(255, 204, 0));
+        const QString text = "This is " + mustard + "mustard" + normal + " text";
+        QTest::newRow("Text-color change (ANSI 256 color)") << text << QTextCharFormat()
+                           << (FormattedTextList()
+                                << FormattedText("This is ", defaultFormat)
+                                << FormattedText("mustard", mustardFormat)
+                                << FormattedText(" text", defaultFormat));
+    }
+
     // Test text format change to bold
     QTextCharFormat boldFormat;
     boldFormat.setFontWeight(QFont::Bold);