3 files changed, 24 insertions, 28 deletions

diff --git a/src/CaseFolder.cxx b/src/CaseFolder.cxx
index b5acc5f96..d66df3f4f 100644
--- a/src/CaseFolder.cxx
+++ b/src/CaseFolder.cxx
@@ -9,53 +9,51 @@
 #include <vector>
 #include <algorithm>
 
+#include "CharacterType.h"
 #include "CaseFolder.h"
 #include "CaseConvert.h"
 
 using namespace Scintilla::Internal;
 
-CaseFolder::~CaseFolder() {
+namespace {
+
+constexpr unsigned char IndexFromChar(char ch) {
+	return static_cast<unsigned char>(ch);
+}
+
 }
 
 CaseFolderTable::CaseFolderTable() noexcept : mapping{}  {
-	for (size_t iChar=0; iChar<sizeof(mapping); iChar++) {
-		mapping[iChar] = static_cast<char>(iChar);
-	}
+	StandardASCII();
 }
 
 size_t CaseFolderTable::Fold(char *folded, size_t sizeFolded, const char *mixed, size_t lenMixed) {
 	if (lenMixed > sizeFolded) {
 		return 0;
-	} else {
-		for (size_t i=0; i<lenMixed; i++) {
-			folded[i] = mapping[static_cast<unsigned char>(mixed[i])];
-		}
-		return lenMixed;
 	}
+	for (size_t i=0; i<lenMixed; i++) {
+		folded[i] = mapping[IndexFromChar(mixed[i])];
+	}
+	return lenMixed;
 }
 
 void CaseFolderTable::SetTranslation(char ch, char chTranslation) noexcept {
-	mapping[static_cast<unsigned char>(ch)] = chTranslation;
+	mapping[IndexFromChar(ch)] = chTranslation;
 }
 
 void CaseFolderTable::StandardASCII() noexcept {
-	for (size_t iChar=0; iChar<sizeof(mapping); iChar++) {
-		if (iChar >= 'A' && iChar <= 'Z') {
-			mapping[iChar] = static_cast<char>(iChar - 'A' + 'a');
-		} else {
-			mapping[iChar] = static_cast<char>(iChar);
-		}
+	for (size_t iChar=0; iChar<std::size(mapping); iChar++) {
+		mapping[iChar] = static_cast<char>(MakeLowerCase(iChar));
 	}
 }
 
 CaseFolderUnicode::CaseFolderUnicode() {
-	StandardASCII();
 	converter = ConverterFor(CaseConversion::fold);
 }
 
 size_t CaseFolderUnicode::Fold(char *folded, size_t sizeFolded, const char *mixed, size_t lenMixed) {
 	if ((lenMixed == 1) && (sizeFolded > 0)) {
-		folded[0] = mapping[static_cast<unsigned char>(mixed[0])];
+		folded[0] = mapping[IndexFromChar(mixed[0])];
 		return 1;
 	} else {
 		return converter->CaseConvertString(folded, sizeFolded, mixed, lenMixed);
diff --git a/src/CaseFolder.h b/src/CaseFolder.h
index 45abe4d8f..4f16ed69c 100644
--- a/src/CaseFolder.h
+++ b/src/CaseFolder.h
@@ -12,7 +12,13 @@ namespace Scintilla::Internal {
 
 class CaseFolder {
 public:
-	virtual ~CaseFolder();
+	CaseFolder() = default;
+	// Deleted so CaseFolder objects can not be copied.
+	CaseFolder(const CaseFolder &source) = delete;
+	CaseFolder(CaseFolder &&) = delete;
+	CaseFolder &operator=(const CaseFolder &) = delete;
+	CaseFolder &operator=(CaseFolder &&) = delete;
+	virtual ~CaseFolder() = default;
 	virtual size_t Fold(char *folded, size_t sizeFolded, const char *mixed, size_t lenMixed) = 0;
 };
 
diff --git a/src/Editor.cxx b/src/Editor.cxx
index d5e6a92ff..6ff0f2d97 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -4084,17 +4084,9 @@ void Editor::Indent(bool forwards) {
 	ContainerNeedsUpdate(Update::Selection);
 }
 
-class CaseFolderASCII : public CaseFolderTable {
-public:
-	CaseFolderASCII() noexcept {
-		StandardASCII();
-	}
-};
-
-
 std::unique_ptr<CaseFolder> Editor::CaseFolderForEncoding() {
 	// Simple default that only maps ASCII upper case to lower case.
-	return std::make_unique<CaseFolderASCII>();
+	return std::make_unique<CaseFolderTable>();
 }
 
 /**