Implement LineEnd method in CellBuffer as it is a basic function and only uses

CellBuffer fields.
Declare LineEnd noexcept as it should never throw and that allows methods
calling it to also be noexcept.
Call LineEndPosition to simplify Editor::LineSelectionRange.

5 files changed, 40 insertions, 37 deletions

diff --git a/src/CellBuffer.cxx b/src/CellBuffer.cxx
index ba11f1391..4b061db40 100644
--- a/src/CellBuffer.cxx
+++ b/src/CellBuffer.cxx
@@ -848,6 +848,33 @@ Sci::Position CellBuffer::LineStart(Sci::Line line) const noexcept {
 		return plv->LineStart(line);
 }
 
+Sci::Position CellBuffer::LineEnd(Sci::Line line) const noexcept {
+	if (line >= Lines() - 1) {
+		return LineStart(line + 1);
+	} else {
+		Sci::Position position = LineStart(line + 1);
+		if (LineEndType::Unicode == GetLineEndTypes()) {
+			const unsigned char bytes[] = {
+				UCharAt(position - 3),
+				UCharAt(position - 2),
+				UCharAt(position - 1),
+			};
+			if (UTF8IsSeparator(bytes)) {
+				return position - UTF8SeparatorLength;
+			}
+			if (UTF8IsNEL(bytes + 1)) {
+				return position - UTF8NELLength;
+			}
+		}
+		position--; // Back over CR or LF
+		// When line terminator is CR+LF, may need to go back one more
+		if ((position > LineStart(line)) && (CharAt(position - 1) == '\r')) {
+			position--;
+		}
+		return position;
+	}
+}
+
 Sci::Line CellBuffer::LineFromPosition(Sci::Position pos) const noexcept {
 	return plv->LineFromPosition(pos);
 }
diff --git a/src/CellBuffer.h b/src/CellBuffer.h
index 7f0b87c4d..f0aacf8ec 100644
--- a/src/CellBuffer.h
+++ b/src/CellBuffer.h
@@ -186,6 +186,7 @@ public:
 	Sci::Line Lines() const noexcept;
 	void AllocateLines(Sci::Line lines);
 	Sci::Position LineStart(Sci::Line line) const noexcept;
+	Sci::Position LineEnd(Sci::Line line) const noexcept;
 	Sci::Position IndexLineStart(Sci::Line line, Scintilla::LineCharacterIndexType lineCharacterIndex) const noexcept;
 	Sci::Line LineFromPosition(Sci::Position pos) const noexcept;
 	Sci::Line LineFromPositionIndex(Sci::Position pos, Scintilla::LineCharacterIndexType lineCharacterIndex) const noexcept;
diff --git a/src/Document.cxx b/src/Document.cxx
index a45479e4b..afe6717a1 100644
--- a/src/Document.cxx
+++ b/src/Document.cxx
@@ -458,30 +458,7 @@ bool Document::IsLineStartPosition(Sci::Position position) const {
 }
 
 Sci_Position SCI_METHOD Document::LineEnd(Sci_Position line) const {
-	if (line >= LinesTotal() - 1) {
-		return LineStart(line + 1);
-	} else {
-		Sci::Position position = LineStart(line + 1);
-		if (LineEndType::Unicode == cb.GetLineEndTypes()) {
-			const unsigned char bytes[] = {
-				cb.UCharAt(position-3),
-				cb.UCharAt(position-2),
-				cb.UCharAt(position-1),
-			};
-			if (UTF8IsSeparator(bytes)) {
-				return position - UTF8SeparatorLength;
-			}
-			if (UTF8IsNEL(bytes+1)) {
-				return position - UTF8NELLength;
-			}
-		}
-		position--; // Back over CR or LF
-		// When line terminator is CR+LF, may need to go back one more
-		if ((position > LineStart(line)) && (cb.CharAt(position - 1) == '\r')) {
-			position--;
-		}
-		return position;
-	}
+	return cb.LineEnd(line);
 }
 
 void SCI_METHOD Document::SetErrorStatus(int status) {
@@ -500,16 +477,16 @@ Sci::Line Document::SciLineFromPosition(Sci::Position pos) const noexcept {
 	return cb.LineFromPosition(pos);
 }
 
-Sci::Position Document::LineEndPosition(Sci::Position position) const {
-	return LineEnd(LineFromPosition(position));
+Sci::Position Document::LineEndPosition(Sci::Position position) const noexcept {
+	return cb.LineEnd(cb.LineFromPosition(position));
 }
 
-bool Document::IsLineEndPosition(Sci::Position position) const {
-	return LineEnd(LineFromPosition(position)) == position;
+bool Document::IsLineEndPosition(Sci::Position position) const noexcept {
+	return LineEndPosition(position) == position;
 }
 
-bool Document::IsPositionInLineEnd(Sci::Position position) const {
-	return position >= LineEnd(LineFromPosition(position));
+bool Document::IsPositionInLineEnd(Sci::Position position) const noexcept {
+	return position >= LineEndPosition(position);
 }
 
 Sci::Position Document::VCHomePosition(Sci::Position position) const {
diff --git a/src/Document.h b/src/Document.h
index 72ed532b3..8889d6454 100644
--- a/src/Document.h
+++ b/src/Document.h
@@ -457,9 +457,9 @@ public:
 	[[nodiscard]] Range LineRange(Sci::Line line) const noexcept;
 	bool IsLineStartPosition(Sci::Position position) const;
 	Sci_Position SCI_METHOD LineEnd(Sci_Position line) const override;
-	Sci::Position LineEndPosition(Sci::Position position) const;
-	bool IsLineEndPosition(Sci::Position position) const;
-	bool IsPositionInLineEnd(Sci::Position position) const;
+	Sci::Position LineEndPosition(Sci::Position position) const noexcept;
+	bool IsLineEndPosition(Sci::Position position) const noexcept;
+	bool IsPositionInLineEnd(Sci::Position position) const noexcept;
 	Sci::Position VCHomePosition(Sci::Position position) const;
 	Sci::Position IndexLineStart(Sci::Line line, Scintilla::LineCharacterIndexType lineCharacterIndex) const noexcept;
 	Sci::Line LineFromPositionIndex(Sci::Position pos, Scintilla::LineCharacterIndexType lineCharacterIndex) const noexcept;
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 80436fd21..dd2fc7e98 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -625,13 +625,11 @@ SelectionRange Editor::LineSelectionRange(SelectionPosition currentPos_, Selecti
 	if (currentPos_ > anchor_) {
 		anchor_ = SelectionPosition(
 			pdoc->LineStart(pdoc->LineFromPosition(anchor_.Position())));
-		currentPos_ = SelectionPosition(
-			pdoc->LineEnd(pdoc->LineFromPosition(currentPos_.Position())));
+		currentPos_ = SelectionPosition(pdoc->LineEndPosition(currentPos_.Position()));
 	} else {
 		currentPos_ = SelectionPosition(
 			pdoc->LineStart(pdoc->LineFromPosition(currentPos_.Position())));
-		anchor_ = SelectionPosition(
-			pdoc->LineEnd(pdoc->LineFromPosition(anchor_.Position())));
+		anchor_ = SelectionPosition(pdoc->LineEndPosition(anchor_.Position()));
 	}
 	return SelectionRange(currentPos_, anchor_);
 }