Simplify text format handling in syntax highlighters

Pass the mapping from custom enum to text style in form of a function,
which then can use a switch which is checked by compilers, and
avoids the need to lookup a different enum somewhere else to find
out what the mapping actually is.
That mapping is cached to keep performance as before.

Also, most highlighters created an enum just for the purpose of mapping
to text styles, basically creating duplicated subsets of text style like
enums everywhere. Instead provide a default, identity mapping from text
styles to text styles.

Change-Id: I2ea1ca702b99e36b8742dfda510b1b2753f0a1c2
Reviewed-by: David Schulz <david.schulz@qt.io>

1 files changed, 19 insertions, 33 deletions

diff --git a/src/plugins/cppeditor/cpphighlighter.cpp b/src/plugins/cppeditor/cpphighlighter.cpp
index 571d7ab9b1..020af2cf3e 100644
--- a/src/plugins/cppeditor/cpphighlighter.cpp
+++ b/src/plugins/cppeditor/cpphighlighter.cpp
@@ -42,21 +42,7 @@ using namespace CPlusPlus;
 CppHighlighter::CppHighlighter(QTextDocument *document) :
     SyntaxHighlighter(document)
 {
-    static const QVector<TextStyle> categories({
-        C_NUMBER,
-        C_STRING,
-        C_TYPE,
-        C_KEYWORD,
-        C_PRIMITIVE_TYPE,
-        C_OPERATOR,
-        C_PREPROCESSOR,
-        C_LABEL,
-        C_COMMENT,
-        C_DOXYGEN_COMMENT,
-        C_DOXYGEN_TAG,
-        C_VISUAL_WHITESPACE
-    });
-    setTextFormatCategories(categories);
+    setDefaultTextFormatCategories();
 }
 
 void CppHighlighter::highlightBlock(const QString &text)
@@ -90,11 +76,11 @@ void CppHighlighter::highlightBlock(const QString &text)
         TextDocumentLayout::clearParentheses(currentBlock());
         if (text.length())  {// the empty line can still contain whitespace
             if (initialLexerState == T_COMMENT)
-                highlightLine(text, 0, text.length(), formatForCategory(CppCommentFormat));
+                highlightLine(text, 0, text.length(), formatForCategory(C_COMMENT));
             else if (initialLexerState == T_DOXY_COMMENT)
-                highlightLine(text, 0, text.length(), formatForCategory(CppDoxygenCommentFormat));
+                highlightLine(text, 0, text.length(), formatForCategory(C_DOXYGEN_COMMENT));
             else
-                setFormat(0, text.length(), formatForCategory(CppVisualWhitespace));
+                setFormat(0, text.length(), formatForCategory(C_VISUAL_WHITESPACE));
         }
         TextDocumentLayout::setFoldingIndent(currentBlock(), foldingIndent);
         return;
@@ -121,7 +107,7 @@ void CppHighlighter::highlightBlock(const QString &text)
         if (previousTokenEnd != tk.utf16charsBegin()) {
             setFormat(previousTokenEnd,
                       tk.utf16charsBegin() - previousTokenEnd,
-                      formatForCategory(CppVisualWhitespace));
+                      formatForCategory(C_VISUAL_WHITESPACE));
         }
 
         if (tk.is(T_LPAREN) || tk.is(T_LBRACE) || tk.is(T_LBRACKET)) {
@@ -162,12 +148,12 @@ void CppHighlighter::highlightBlock(const QString &text)
 
         if (i == 0 && tk.is(T_POUND)) {
             highlightLine(text, tk.utf16charsBegin(), tk.utf16chars(),
-                          formatForCategory(CppPreprocessorFormat));
+                          formatForCategory(C_PREPROCESSOR));
             expectPreprocessorKeyword = true;
         } else if (highlightCurrentWordAsPreprocessor
                    && (tk.isKeyword() || tk.is(T_IDENTIFIER))
                    && isPPKeyword(text.midRef(tk.utf16charsBegin(), tk.utf16chars()))) {
-            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppPreprocessorFormat));
+            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_PREPROCESSOR));
             const QStringRef ppKeyword = text.midRef(tk.utf16charsBegin(), tk.utf16chars());
             if (ppKeyword == QLatin1String("error")
                     || ppKeyword == QLatin1String("warning")
@@ -176,14 +162,14 @@ void CppHighlighter::highlightBlock(const QString &text)
             }
 
         } else if (tk.is(T_NUMERIC_LITERAL)) {
-            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppNumberFormat));
+            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_NUMBER));
         } else if (tk.isStringLiteral() || tk.isCharLiteral()) {
-            highlightLine(text, tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppStringFormat));
+            highlightLine(text, tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_STRING));
         } else if (tk.isComment()) {
             const int startPosition = initialLexerState ? previousTokenEnd : tk.utf16charsBegin();
             if (tk.is(T_COMMENT) || tk.is(T_CPP_COMMENT)) {
                 highlightLine(text, startPosition, tk.utf16charsEnd() - startPosition,
-                              formatForCategory(CppCommentFormat));
+                              formatForCategory(C_COMMENT));
             }
 
             else // a doxygen comment
@@ -211,14 +197,14 @@ void CppHighlighter::highlightBlock(const QString &text)
                    || (m_languageFeatures.qtKeywordsEnabled
                        && CppTools::isQtKeyword(text.midRef(tk.utf16charsBegin(), tk.utf16chars())))
                    || (m_languageFeatures.objCEnabled && tk.isObjCAtKeyword())) {
-            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppKeywordFormat));
+            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_KEYWORD));
         } else if (tk.isPrimitiveType()) {
             setFormat(tk.utf16charsBegin(), tk.utf16chars(),
-                      formatForCategory(CppPrimitiveTypeFormat));
+                      formatForCategory(C_PRIMITIVE_TYPE));
         } else if (tk.isOperator()) {
-            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppOperatorFormat));
+            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_OPERATOR));
         } else if (i == 0 && tokens.size() > 1 && tk.is(T_IDENTIFIER) && tokens.at(1).is(T_COLON)) {
-            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(CppLabelFormat));
+            setFormat(tk.utf16charsBegin(), tk.utf16chars(), formatForCategory(C_LABEL));
         } else if (tk.is(T_IDENTIFIER)) {
             highlightWord(text.midRef(tk.utf16charsBegin(), tk.utf16chars()), tk.utf16charsBegin(),
                           tk.utf16chars());
@@ -228,7 +214,7 @@ void CppHighlighter::highlightBlock(const QString &text)
     // mark the trailing white spaces
     const int lastTokenEnd = tokens.last().utf16charsEnd();
     if (text.length() > lastTokenEnd)
-        highlightLine(text, lastTokenEnd, text.length() - lastTokenEnd, formatForCategory(CppVisualWhitespace));
+        highlightLine(text, lastTokenEnd, text.length() - lastTokenEnd, formatForCategory(C_VISUAL_WHITESPACE));
 
     if (!initialLexerState && lexerState && !tokens.isEmpty()) {
         const Token &lastToken = tokens.last();
@@ -360,7 +346,7 @@ bool CppHighlighter::isPPKeyword(const QStringRef &text) const
 void CppHighlighter::highlightLine(const QString &text, int position, int length,
                                    const QTextCharFormat &format)
 {
-    QTextCharFormat visualSpaceFormat = formatForCategory(CppVisualWhitespace);
+    QTextCharFormat visualSpaceFormat = formatForCategory(C_VISUAL_WHITESPACE);
     visualSpaceFormat.setBackground(format.background());
 
     const int end = position + length;
@@ -394,7 +380,7 @@ void CppHighlighter::highlightWord(QStringRef word, int position, int length)
                     return;
             }
 
-            setFormat(position, length, formatForCategory(CppTypeFormat));
+            setFormat(position, length, formatForCategory(C_TYPE));
         }
     }
 }
@@ -406,8 +392,8 @@ void CppHighlighter::highlightDoxygenComment(const QString &text, int position,
     const QChar *uc = text.unicode();
     const QChar *it = uc + position;
 
-    const QTextCharFormat &format = formatForCategory(CppDoxygenCommentFormat);
-    const QTextCharFormat &kwFormat = formatForCategory(CppDoxygenTagFormat);
+    const QTextCharFormat &format = formatForCategory(C_DOXYGEN_COMMENT);
+    const QTextCharFormat &kwFormat = formatForCategory(C_DOXYGEN_TAG);
 
     while (!it->isNull()) {
         if (it->unicode() == QLatin1Char('\\') ||