Draw invisible chars only for control characters (fix #962)

CHANGELOG.md

@@ -2,6 +2,16 @@
 Change Log
 ==========================
 
+3.7.6 (unreleased)
+--------------------------
+
+### Fixes
+
+- Fix an issue where an unwanted whitespace was added for variation selector `U+FE0E` when control characters are visible.
+
+
+
+
 3.7.5 (353)
 --------------------------
 

CotEditor/Sources/ATSTypesetter.swift

@@ -55,7 +55,8 @@ final class ATSTypesetter: NSATSTypesetter {
         
         if action.contains(.zeroAdvancementAction),
             let character = (self.attributedString?.string as NSString?)?.character(at: charIndex),
-            !UTF16.isTrailSurrogate(character)  // ignore one of surrogate
+            let unicode = Unicode.Scalar(character),
+            unicode.properties.generalCategory == .control
         {
             return .whitespaceAction  // -> Then, the glyph width can be modified on `boundingBox(forControlGlyphAt:...)`.
         }