[HTML][JavaScript][VBScript] Code simplify and cleanup

[zufuliu]

Opened to discuss and backport zufuliu/notepad4@1c2360f

1. else if (state == SCE_HBA_DEFAULT) block is not reachable after int state = stateForPrintState(StateToPrint);, and can be merged with preceding if (state == SCE_HB_DEFAULT) block.
   

   lexilla/lexers/LexHTML.cxx

   Lines 2706 to 2716 in c14de3d

   	} else if (state == SCE_HBA_DEFAULT) { // One of the above succeeded
   	if ((ch == '\"') && (nonEmptySegment)) {
   	state = SCE_HBA_STRING;
   	} else if (ch == '\'') {
   	state = SCE_HBA_COMMENTLINE;
   	} else if (IsAWordStart(ch)) {
   	state = SCE_HBA_WORD;
   	} else if (IsOperator(ch)) {
   	styler.ColourTo(i, SCE_HBA_DEFAULT);
   	}
   	} else if (state == SCE_HJ_DEFAULT) { // One of the above succeeded

2. if (state == SCE_HB_DEFAULT) block inside case SCE_HB_WORD: can be merged with if (state == SCE_HB_DEFAULT) block after the big switch.
   

   lexilla/lexers/LexHTML.cxx

   Lines 2379 to 2390 in c14de3d

   	if (state == SCE_HB_DEFAULT) {
   	if (ch == '\"') {
   	state = SCE_HB_STRING;
   	} else if (ch == '\'') {
   	state = SCE_HB_COMMENTLINE;
   	} else if (IsOperator(ch)) {
   	styler.ColourTo(i, statePrintForState(SCE_HB_DEFAULT, inScriptType));
   	state = SCE_HB_DEFAULT;
   	}
   	}
   	}
   	break;

   
   

   lexilla/lexers/LexHTML.cxx

   Lines 2696 to 2706 in c14de3d

   	if (state == SCE_HB_DEFAULT) { // One of the above succeeded
   	if ((ch == '\"') && (nonEmptySegment)) {
   	state = SCE_HB_STRING;
   	} else if (ch == '\'') {
   	state = SCE_HB_COMMENTLINE;
   	} else if (IsAWordStart(ch)) {
   	state = SCE_HB_WORD;
   	} else if (IsOperator(ch)) {
   	styler.ColourTo(i, SCE_HB_DEFAULT);
   	}
   	} else if (state == SCE_HBA_DEFAULT) { // One of the above succeeded

3. state change block inside case SCE_HJ_WORD: can be merged with else if (state == SCE_HJ_DEFAULT) block after the big switch.
   

   lexilla/lexers/LexHTML.cxx

   Lines 2240 to 2264 in c14de3d

   	state = SCE_HJ_DEFAULT;
   	if (ch == '/' && chNext == '*') {
   	i++;
   	if (chNext2 == '*')
   	state = SCE_HJ_COMMENTDOC;
   	else
   	state = SCE_HJ_COMMENT;
   	} else if (ch == '/' && chNext == '/') {
   	state = SCE_HJ_COMMENTLINE;
   	} else if (ch == '\"') {
   	state = SCE_HJ_DOUBLESTRING;
   	} else if (ch == '\'') {
   	state = SCE_HJ_SINGLESTRING;
   	} else if (ch == '`') {
   	state = SCE_HJ_TEMPLATELITERAL;
   	} else if ((ch == '-') && (chNext == '-') && (chNext2 == '>')) {
   	styler.ColourTo(i - 1, StateToPrint);
   	state = SCE_HJ_COMMENTLINE;
   	i += 2;
   	} else if (IsOperator(ch)) {
   	styler.ColourTo(i, statePrintForState(SCE_HJ_SYMBOLS, inScriptType));
   	state = SCE_HJ_DEFAULT;
   	}
   	}
   	break;

   
   

   lexilla/lexers/LexHTML.cxx

   Lines 2716 to 2736 in c14de3d

   	} else if (state == SCE_HJ_DEFAULT) { // One of the above succeeded
   	if (ch == '/' && chNext == '*') {
   	i++;
   	if (styler.SafeGetCharAt(i + 1) == '*')
   	state = SCE_HJ_COMMENTDOC;
   	else
   	state = SCE_HJ_COMMENT;
   	} else if (ch == '/' && chNext == '/') {
   	state = SCE_HJ_COMMENTLINE;
   	} else if ((ch == '\"') && (nonEmptySegment)) {
   	state = SCE_HJ_DOUBLESTRING;
   	} else if ((ch == '\'') && (nonEmptySegment)) {
   	state = SCE_HJ_SINGLESTRING;
   	} else if ((ch == '`') && (nonEmptySegment)) {
   	state = SCE_HJ_TEMPLATELITERAL;
   	} else if (IsAWordStart(ch)) {
   	state = SCE_HJ_WORD;
   	} else if (IsOperator(ch)) {
   	styler.ColourTo(i, statePrintForState(SCE_HJ_SYMBOLS, inScriptType));
   	}
   	}

4. nonEmptySegment check could be eliminated by using continue.
   

   lexilla/lexers/LexHTML.cxx

   Line 2695 in c14de3d

   const bool nonEmptySegment = i >= static_cast<Sci_Position>(styler.GetStartSegment());

Other changes not yet made:

1. bool tagOpened is never used / tested, so can be removed.
   

   lexilla/lexers/LexHTML.cxx

   Line 1246 in c14de3d

   bool tagOpened = (lineState >> 2) & 0x01; // 1 bit to know if we are in an opened tag

2. Due to backtracking to start of line not inside tag states, bool tagClosing and bool isLanguageType can be omitted from lineState.
   

   lexilla/lexers/LexHTML.cxx

   Lines 1206 to 1209 in c14de3d

   	// If inside a tag, it may be a script tag, so reread from the start of line starting tag to ensure any language tags are seen
   	// PHP string can be heredoc, must find a delimiter first. Reread from beginning of line containing the string, to get the correct lineState
   	if (StyleNeedsBacktrack(state)) {
   	while ((startPos > 0) && (StyleNeedsBacktrack(styler.StyleIndexAt(startPos - 1)))) {

   
   

   lexilla/lexers/LexHTML.cxx

   Lines 671 to 673 in c14de3d

   	constexpr bool StyleNeedsBacktrack(int state) noexcept {
   	return InTagState(state) || isPHPStringState(state);
   	}

3. (Maybe complex changes) defer and merge state change for JavaScript and VBScript to blocks after the big switch.

   lexilla/lexers/LexHTML.cxx

   Lines 2188 to 2191 in c14de3d

   	case SCE_HJ_DEFAULT:
   	case SCE_HJ_START:
   	case SCE_HJ_SYMBOLS:
   	if (IsAWordStart(ch)) {

   
   

   lexilla/lexers/LexHTML.cxx

   Lines 2350 to 2352 in c14de3d

   	case SCE_HB_DEFAULT:
   	case SCE_HB_START:
   	if (IsAWordStart(ch)) {