Add SCI_REPLACETARGETMINIMAL to change text without causing unchanged prefix and

suffix to be marked as modified in change history.

4 files changed, 50 insertions, 11 deletions

diff --git a/src/Document.cxx b/src/Document.cxx
index 0237cef78..6a638471d 100644
--- a/src/Document.cxx
+++ b/src/Document.cxx
@@ -1242,6 +1242,17 @@ void Document::CheckReadOnly() {
 	}
 }
 
+void Document::TrimReplacement(std::string_view &text, Range &range) const noexcept {
+	while (!text.empty() && !range.Empty() && (text.front() == CharAt(range.start))) {
+		text.remove_prefix(1);
+		range.start++;
+	}
+	while (!text.empty() && !range.Empty() && (text.back() == CharAt(range.end-1))) {
+		text.remove_suffix(1);
+		range.end--;
+	}
+}
+
 // Document only modified by gateways DeleteChars, InsertString, Undo, Redo, and SetStyleAt.
 // SetStyleAt does not change the persistent state of a document
 
diff --git a/src/Document.h b/src/Document.h
index ae784180a..ac9c6670c 100644
--- a/src/Document.h
+++ b/src/Document.h
@@ -46,6 +46,10 @@ public:
 		return (start != Sci::invalidPosition) && (end != Sci::invalidPosition);
 	}
 
+	[[nodiscard]] bool Empty() const noexcept {
+		return start == end;
+	}
+
 	Sci::Position First() const noexcept {
 		return (start <= end) ? start : end;
 	}
@@ -369,6 +373,7 @@ public:
 	// Gateways to modifying document
 	void ModifiedAt(Sci::Position pos) noexcept;
 	void CheckReadOnly();
+	void TrimReplacement(std::string_view &text, Range &range) const noexcept;
 	bool DeleteChars(Sci::Position pos, Sci::Position len);
 	Sci::Position InsertString(Sci::Position position, const char *s, Sci::Position insertLength);
 	Sci::Position InsertString(Sci::Position position, std::string_view sv);
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 2e1467e32..1fb6d960d 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -5696,15 +5696,27 @@ Sci::Position Editor::GetTag(char *tagValue, int tagNumber) {
 	return length;
 }
 
-Sci::Position Editor::ReplaceTarget(bool replacePatterns, const char *text, Sci::Position length) {
+Sci::Position Editor::ReplaceTarget(ReplaceType replaceType, std::string_view text) {
 	UndoGroup ug(pdoc);
-	if (length == -1)
-		length = strlen(text);
-	if (replacePatterns) {
-		text = pdoc->SubstituteByPosition(text, &length);
-		if (!text) {
+	if (replaceType == ReplaceType::patterns) {
+		Sci::Position length = text.length();
+		const char *p = pdoc->SubstituteByPosition(text.data(), &length);
+		if (!p) {
 			return 0;
 		}
+		text = std::string_view(p, length);
+	}
+
+	if (replaceType == ReplaceType::minimal) {
+		// Check for prefix and suffix and reduce text and target to match.
+		// This is performed with Range which doesn't support virtual space.
+		Range range(targetRange.start.Position(), targetRange.end.Position());
+		pdoc->TrimReplacement(text, range);
+		// Re-apply virtual space to start if start position didn't change.
+		// Don't bother with end as its virtual space is not used
+		const SelectionPosition start(range.start == targetRange.start.Position() ?
+			targetRange.start : SelectionPosition(range.start));
+		targetRange = SelectionSegment(start, SelectionPosition(range.end));
 	}
 
 	// Remove the text inside the range
@@ -5718,9 +5730,9 @@ Sci::Position Editor::ReplaceTarget(bool replacePatterns, const char *text, Sci:
 	targetRange.end = targetRange.start;
 
 	// Insert the new text
-	const Sci::Position lengthInserted = pdoc->InsertString(targetRange.start.Position(), text, length);
+	const Sci::Position lengthInserted = pdoc->InsertString(targetRange.start.Position(), text);
 	targetRange.end.SetPosition(targetRange.start.Position() + lengthInserted);
-	return length;
+	return text.length();
 }
 
 bool Editor::IsUnicodeMode() const noexcept {
@@ -6240,11 +6252,15 @@ sptr_t Editor::WndProc(Message iMessage, uptr_t wParam, sptr_t lParam) {
 
 	case Message::ReplaceTarget:
 		PLATFORM_ASSERT(lParam);
-		return ReplaceTarget(false, ConstCharPtrFromSPtr(lParam), PositionFromUPtr(wParam));
+		return ReplaceTarget(ReplaceType::basic, ViewFromParams(lParam, wParam));
 
 	case Message::ReplaceTargetRE:
 		PLATFORM_ASSERT(lParam);
-		return ReplaceTarget(true, ConstCharPtrFromSPtr(lParam), PositionFromUPtr(wParam));
+		return ReplaceTarget(ReplaceType::patterns, ViewFromParams(lParam, wParam));
+
+	case Message::ReplaceTargetMinimal:
+		PLATFORM_ASSERT(lParam);
+		return ReplaceTarget(ReplaceType::minimal, ViewFromParams(lParam, wParam));
 
 	case Message::SearchInTarget:
 		PLATFORM_ASSERT(lParam);
diff --git a/src/Editor.h b/src/Editor.h
index 128abf234..85d95e21d 100644
--- a/src/Editor.h
+++ b/src/Editor.h
@@ -581,7 +581,8 @@ protected:	// ScintillaBase subclass needs access to much of Editor
 	void FoldAll(Scintilla::FoldAction action);
 
 	Sci::Position GetTag(char *tagValue, int tagNumber);
-	Sci::Position ReplaceTarget(bool replacePatterns, const char *text, Sci::Position length=-1);
+	enum class ReplaceType {basic, patterns, minimal};
+	Sci::Position ReplaceTarget(ReplaceType replaceType, std::string_view text);
 
 	bool PositionIsHotspot(Sci::Position position) const noexcept;
 	bool PointIsHotspot(Point pt);
@@ -625,6 +626,12 @@ protected:	// ScintillaBase subclass needs access to much of Editor
 	static unsigned char *UCharPtrFromSPtr(Scintilla::sptr_t lParam) noexcept {
 		return static_cast<unsigned char *>(PtrFromSPtr(lParam));
 	}
+	static std::string_view ViewFromParams(Scintilla::sptr_t lParam, Scintilla::uptr_t wParam) noexcept {
+		if (SPtrFromUPtr(wParam) == -1) {
+			return std::string_view(CharPtrFromSPtr(lParam));
+		}
+		return std::string_view(CharPtrFromSPtr(lParam), wParam);
+	}
 	static void *PtrFromUPtr(Scintilla::uptr_t wParam) noexcept {
 		return reinterpret_cast<void *>(wParam);
 	}