LexProps: don't set header flag for empty section

[zufuliu]

To prevent FoldAction::Toggle failure and avoid showing fold display text after toggle folds.

diff --git a/lexers/LexProps.cxx b/lexers/LexProps.cxx
index 7dadb2c6..b869659a 100644
--- a/lexers/LexProps.cxx
+++ b/lexers/LexProps.cxx
@@ -154,6 +154,10 @@ static void FoldPropsDoc(Sci_PositionU startPos, Sci_Position length, int, WordL
 
 			if (headerPoint) {
 				lev |= SC_FOLDLEVELHEADERFLAG;
+				if (levelPrevious & SC_FOLDLEVELHEADERFLAG) {
+					// empty section
+					styler.SetLevel(lineCurrent - 1, SC_FOLDLEVELBASE);
+				}
 			}
 			if (lev != styler.LevelAt(lineCurrent)) {
 				styler.SetLevel(lineCurrent, lev);

[nyamatongwe]

Is there an example file?

[zufuliu]

An example, toggle folds not fails in SciTE (not sure why), fold display text can't be tested in SciTE.

; comment
[empty section]
[normal section]
@=default
key=value

Edit: updated example to list all styles.

[zufuliu]

Full code for FoldPropsDoc(), moved levelPrevious out from the loop.
FoldPropsDoc.zip

[nyamatongwe]

FoldPropsDoc.zip won't compile as lev is used in the epilogue but its declaration is now in an inner scope. I expect it would be better as:

	int lev = levelPrevious & SC_FOLDLEVELNUMBERMASK;
	if (levelPrevious & SC_FOLDLEVELHEADERFLAG) {
		lev = SC_FOLDLEVELBASE + 1;
	}

Or with another name to avoid shadowing. The inner declaration of lev could also be initialised to levelPrevious & SC_FOLDLEVELNUMBERMASK to avoid uninitialized variable warnings.

[zufuliu]

It seems last styler.SetLevel(lineCurrent, lev | (flagsNext & ~SC_FOLDLEVELNUMBERMASK)); can be removed (change inner code to use if (atEOL || i == (endPos - 1)) {), not sure what it want archive.

[nyamatongwe]

This pattern is used to avoid transient changes (and potential unfolding) due to not running the full logic past the end. It may or may not be needed in this case.

[zufuliu]

Changed to following

int level = levelPrevious & SC_FOLDLEVELNUMBERMASK;
if (levelPrevious & SC_FOLDLEVELHEADERFLAG) {
	level += 1;
}

FoldPropsDoc-0727.zip

[nyamatongwe]

Included in 5.1.9.