Added SCI_CONTRACTEDFOLDNEXT as a way to find contracted fold headers efficiently.

7 files changed, 49 insertions, 1 deletions

diff --git a/doc/ScintillaDoc.html b/doc/ScintillaDoc.html
index fbffd64aa..02747ee69 100644
--- a/doc/ScintillaDoc.html
+++ b/doc/ScintillaDoc.html
@@ -4699,6 +4699,7 @@ sptr_t CallScintilla(unsigned int iMessage, uptr_t wParam, sptr_t lParam){
      <a class="message" href="#SCI_SETFOLDEXPANDED">SCI_SETFOLDEXPANDED(int line, bool
     expanded)</a><br />
      <a class="message" href="#SCI_GETFOLDEXPANDED">SCI_GETFOLDEXPANDED(int line)</a><br />
+     <a class="message" href="#SCI_CONTRACTEDFOLDNEXT">SCI_CONTRACTEDFOLDNEXT(int lineStart)</a><br />
      <a class="message" href="#SCI_TOGGLEFOLD">SCI_TOGGLEFOLD(int line)</a><br />
      <a class="message" href="#SCI_ENSUREVISIBLE">SCI_ENSUREVISIBLE(int line)</a><br />
      <a class="message" href="#SCI_ENSUREVISIBLEENFORCEPOLICY">SCI_ENSUREVISIBLEENFORCEPOLICY(int
@@ -4849,6 +4850,13 @@ sptr_t CallScintilla(unsigned int iMessage, uptr_t wParam, sptr_t lParam){
     until you had finished. See <code>SciTEBase::FoldAll()</code> and
     <code>SciTEBase::Expand()</code> for examples of the use of these messages.</p>
 
+    <p><b id="SCI_CONTRACTEDFOLDNEXT">SCI_CONTRACTEDFOLDNEXT(int lineStart)</b><br />
+     Search efficiently for lines that are contracted fold headers. 
+     This is useful when saving the user's folding when switching documents or saving folding with a file. 
+     The search starts at line number <code>lineStart</code> and continues forwards to the end of the file.
+     <code>lineStart</code> is returned if it is a contracted fold header otherwise the next contracted
+     fold header is returned. If there are no more contracted fold headers then -1 is returned.</p>
+
     <p><b id="SCI_ENSUREVISIBLE">SCI_ENSUREVISIBLE(int line)</b><br />
      <b id="SCI_ENSUREVISIBLEENFORCEPOLICY">SCI_ENSUREVISIBLEENFORCEPOLICY(int line)</b><br />
      A line may be hidden because more than one of its parent lines is contracted. Both these
diff --git a/include/Scintilla.h b/include/Scintilla.h
index c20a063f9..54f104437 100644
--- a/include/Scintilla.h
+++ b/include/Scintilla.h
@@ -786,6 +786,7 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define SCI_ROTATESELECTION 2606
 #define SCI_SWAPMAINANCHORCARET 2607
 #define SCI_CHANGELEXERSTATE 2617
+#define SCI_CONTRACTEDFOLDNEXT 2618
 #define SCI_STARTRECORD 3001
 #define SCI_STOPRECORD 3002
 #define SCI_SETLEXER 4001
diff --git a/include/Scintilla.iface b/include/Scintilla.iface
index 2516b7134..679bce53b 100644
--- a/include/Scintilla.iface
+++ b/include/Scintilla.iface
@@ -304,7 +304,8 @@ fun void MarkerDeleteAll=2045(int markerNumber,)
 # Get a bit mask of all the markers set on a line.
 fun int MarkerGet=2046(int line,)
 
-# Find the next line after lineStart that includes a marker in mask.
+# Find the next line at or after lineStart that includes a marker in mask.
+# Return -1 when no more lines.
 fun int MarkerNext=2047(int lineStart, int markerMask)
 
 # Find the previous line before lineStart that includes a marker in mask.
@@ -2090,6 +2091,10 @@ fun void SwapMainAnchorCaret=2607(,)
 # there may be a need to redraw.
 fun int ChangeLexerState=2617(position start, position end)
 
+# Find the next line at or after lineStart that is a contracted fold header line.
+# Return -1 when no more lines.
+fun int ContractedFoldNext=2618(int lineStart,)
+
 # Start notifying the container of all key presses and commands.
 fun void StartRecord=3001(,)
 
diff --git a/src/ContractionState.cxx b/src/ContractionState.cxx
index f2cc2f07b..8a1b486e7 100644
--- a/src/ContractionState.cxx
+++ b/src/ContractionState.cxx
@@ -193,6 +193,23 @@ bool ContractionState::SetExpanded(int lineDoc, bool expanded_) {
 	}
 }
 
+int ContractionState::ContractedNext(int lineDocStart) const {
+	if (OneToOne()) {
+		return -1;
+	} else {
+		Check();
+		if (!expanded->ValueAt(lineDocStart)) {
+			return lineDocStart;
+		} else {
+			int lineDocNextChange = expanded->EndRun(lineDocStart);
+			if (lineDocNextChange < LinesInDoc())
+				return lineDocNextChange;
+			else
+				return -1;
+		}
+	}
+}
+
 int ContractionState::GetHeight(int lineDoc) const {
 	if (OneToOne()) {
 		return 1;
diff --git a/src/ContractionState.h b/src/ContractionState.h
index ba6297512..8e7b39b9b 100644
--- a/src/ContractionState.h
+++ b/src/ContractionState.h
@@ -51,6 +51,7 @@ public:
 
 	bool GetExpanded(int lineDoc) const;
 	bool SetExpanded(int lineDoc, bool expanded);
+	int ContractedNext(int lineDocStart) const;
 
 	int GetHeight(int lineDoc) const;
 	bool SetHeight(int lineDoc, int height);
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 762156c23..bca458037 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -6481,6 +6481,18 @@ void Editor::ToggleContraction(int line) {
 	}
 }
 
+int Editor::ContractedFoldNext(int lineStart) {
+	for (int line = lineStart; line<pdoc->LinesTotal(); ) {
+		if (!cs.GetExpanded(line) && (pdoc->GetLevel(line) & SC_FOLDLEVELHEADERFLAG))
+			return line;
+		line = cs.ContractedNext(line+1);
+		if (line < 0)
+			return -1;
+	}
+
+	return -1;
+}
+
 /**
  * Recurse up from this line to find any folds that prevent this line from being visible
  * and unfold them all.
@@ -7866,6 +7878,9 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 		ToggleContraction(wParam);
 		break;
 
+	case SCI_CONTRACTEDFOLDNEXT:
+		return ContractedFoldNext(wParam);
+
 	case SCI_ENSUREVISIBLE:
 		EnsureLineVisible(wParam, false);
 		break;
diff --git a/src/Editor.h b/src/Editor.h
index aa4fc9236..3f36c9088 100644
--- a/src/Editor.h
+++ b/src/Editor.h
@@ -508,6 +508,7 @@ protected:	// ScintillaBase subclass needs access to much of Editor
 
 	void Expand(int &line, bool doExpand);
 	void ToggleContraction(int line);
+	int ContractedFoldNext(int lineStart);
 	void EnsureLineVisible(int lineDoc, bool enforcePolicy);
 	int GetTag(char *tagValue, int tagNumber);
 	int ReplaceTarget(bool replacePatterns, const char *text, int length=-1);