Backport: Feature [feature-requests:#1272]. Add API to set default fold display text.

Backport of changeset 7400:9fcb52fdb307.

7 files changed, 39 insertions, 11 deletions

diff --git a/src/ContractionState.cxx b/src/ContractionState.cxx
index c5e352180..47f345ada 100644
--- a/src/ContractionState.cxx
+++ b/src/ContractionState.cxx
@@ -74,7 +74,6 @@ public:
 	bool HiddenLines() const override;
 
 	const char *GetFoldDisplayText(Sci::Line lineDoc) const override;
-	bool GetFoldDisplayTextShown(Sci::Line lineDoc) const override;
 	bool SetFoldDisplayText(Sci::Line lineDoc, const char *text) override;
 
 	bool GetExpanded(Sci::Line lineDoc) const override;
@@ -277,16 +276,11 @@ const char *ContractionState<LINE>::GetFoldDisplayText(Sci::Line lineDoc) const
 }
 
 template <typename LINE>
-bool ContractionState<LINE>::GetFoldDisplayTextShown(Sci::Line lineDoc) const {
-	return !GetExpanded(lineDoc) && GetFoldDisplayText(lineDoc);
-}
-
-template <typename LINE>
 bool ContractionState<LINE>::SetFoldDisplayText(Sci::Line lineDoc, const char *text) {
 	EnsureData();
 	const char *foldText = foldDisplayTexts->ValueAt(lineDoc).get();
 	if (!foldText || !text || 0 != strcmp(text, foldText)) {
-		UniqueString uns = UniqueStringCopy(text);
+		UniqueString uns = IsNullOrEmpty(text) ? UniqueString() : UniqueStringCopy(text);
 		foldDisplayTexts->SetValueAt(lineDoc, std::move(uns));
 		Check();
 		return true;
diff --git a/src/ContractionState.h b/src/ContractionState.h
index 90f5c0784..f9ec7b645 100644
--- a/src/ContractionState.h
+++ b/src/ContractionState.h
@@ -32,7 +32,6 @@ public:
 	virtual bool HiddenLines() const=0;
 
 	virtual const char *GetFoldDisplayText(Sci::Line lineDoc) const=0;
-	virtual bool GetFoldDisplayTextShown(Sci::Line lineDoc) const=0;
 	virtual bool SetFoldDisplayText(Sci::Line lineDoc, const char *text)=0;
 
 	virtual bool GetExpanded(Sci::Line lineDoc) const=0;
diff --git a/src/EditModel.cxx b/src/EditModel.cxx
index 6288fd1b6..99520f3cb 100644
--- a/src/EditModel.cxx
+++ b/src/EditModel.cxx
@@ -77,3 +77,21 @@ EditModel::~EditModel() {
 	pdoc->Release();
 	pdoc = nullptr;
 }
+
+void EditModel::SetDefaultFoldDisplayText(const char *text) {
+	defaultFoldDisplayText = IsNullOrEmpty(text) ? UniqueString() : UniqueStringCopy(text);
+}
+
+const char *EditModel::GetDefaultFoldDisplayText() const noexcept {
+	return defaultFoldDisplayText.get();
+}
+
+const char *EditModel::GetFoldDisplayText(Sci::Line lineDoc) const {
+	if (foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN || pcs->GetExpanded(lineDoc)) {
+		return nullptr;
+	}
+
+	const char *text = pcs->GetFoldDisplayText(lineDoc);
+	return text ? text : defaultFoldDisplayText.get();
+}
+
diff --git a/src/EditModel.h b/src/EditModel.h
index 5cc9d51d1..ab5c23cdb 100644
--- a/src/EditModel.h
+++ b/src/EditModel.h
@@ -40,6 +40,7 @@ public:
 
 	int foldFlags;
 	int foldDisplayTextStyle;
+	UniqueString defaultFoldDisplayText;
 	std::unique_ptr<IContractionState> pcs;
 	// Hotspot support
 	Range hotspot;
@@ -61,6 +62,9 @@ public:
 	virtual Point GetVisibleOriginInMain() const = 0;
 	virtual Sci::Line LinesOnScreen() const = 0;
 	virtual Range GetHotSpotRange() const noexcept = 0;
+	void SetDefaultFoldDisplayText(const char *text);
+	const char *GetDefaultFoldDisplayText() const noexcept;
+	const char *GetFoldDisplayText(Sci::Line lineDoc) const;
 };
 
 }
diff --git a/src/EditView.cxx b/src/EditView.cxx
index e82f09ee2..fa01a0385 100644
--- a/src/EditView.cxx
+++ b/src/EditView.cxx
@@ -985,7 +985,7 @@ void EditView::DrawEOL(Surface *surface, const EditModel &model, const ViewStyle
 		rcSegment.left = rcLine.left;
 	rcSegment.right = rcLine.right;
 
-	const bool fillRemainder = !lastSubLine || model.foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN || !model.pcs->GetFoldDisplayTextShown(line);
+	const bool fillRemainder = !lastSubLine || !model.GetFoldDisplayText(line);
 	if (fillRemainder) {
 		// Fill the remainder of the line
 		FillLineRemainder(surface, model, vsDraw, ll, line, rcSegment, subLine);
@@ -1105,11 +1105,12 @@ void EditView::DrawFoldDisplayText(Surface *surface, const EditModel &model, con
 	if (!lastSubLine)
 		return;
 
-	if ((model.foldDisplayTextStyle == SC_FOLDDISPLAYTEXT_HIDDEN) || !model.pcs->GetFoldDisplayTextShown(line))
+	const char *text = model.GetFoldDisplayText(line);
+	if (!text)
 		return;
 
 	PRectangle rcSegment = rcLine;
-	const char *foldDisplayText = model.pcs->GetFoldDisplayText(line);
+	const char *foldDisplayText = text;
 	const int lengthFoldDisplayText = static_cast<int>(strlen(foldDisplayText));
 	FontAlias fontText = vsDraw.styles[STYLE_FOLDDISPLAYTEXT].font;
 	const int widthFoldDisplayText = static_cast<int>(surface->WidthText(fontText, foldDisplayText, lengthFoldDisplayText));
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 08a4ac76c..d67f97df7 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -7191,6 +7191,14 @@ sptr_t Editor::WndProc(unsigned int iMessage, uptr_t wParam, sptr_t lParam) {
 	case SCI_FOLDDISPLAYTEXTGETSTYLE:
 		return foldDisplayTextStyle;
 
+	case SCI_SETDEFAULTFOLDDISPLAYTEXT:
+		SetDefaultFoldDisplayText(CharPtrFromSPtr(lParam));
+		Redraw();
+		break;
+
+	case SCI_GETDEFAULTFOLDDISPLAYTEXT:
+		return StringResult(lParam, GetDefaultFoldDisplayText());
+
 	case SCI_TOGGLEFOLD:
 		FoldLine(static_cast<Sci::Line>(wParam), SC_FOLDACTION_TOGGLE);
 		break;
diff --git a/src/UniqueString.h b/src/UniqueString.h
index 18c31283e..8d95cb1ab 100644
--- a/src/UniqueString.h
+++ b/src/UniqueString.h
@@ -11,6 +11,10 @@
 
 namespace Scintilla {
 
+constexpr bool IsNullOrEmpty(const char *text) noexcept {
+	return text == nullptr || *text == '\0';
+}
+
 using UniqueString = std::unique_ptr<const char[]>;
 
 /// Equivalent to strdup but produces a std::unique_ptr<const char[]> allocation to go