Dump the inverted bit of a custom character class

Make sure an inverted character class does not
dump the same as a regular character class.

Author: hamishknight

Sources/_RegexParser/Regex/Printing/DumpAST.swift

@@ -309,7 +309,7 @@ extension AST.CustomCharacterClass: _ASTNode {
     // comparisons of dumped output in tests.
     // TODO: We should eventually have some way of filtering out trivia for
     // tests, so that it can appear in regular dumps.
-    return "customCharacterClass(\(strippingTriviaShallow.members))"
+    return "customCharacterClass(inverted: \(isInverted), \(strippingTriviaShallow.members))"
   }
 }
 

Tests/RegexTests/ParseTests.swift

@@ -2210,6 +2210,8 @@ extension RegexTests {
 
     parseNotEqualTest(#"[abc]"#, #"[a b c]"#)
 
+    parseNotEqualTest("[abc]", "[^abc]")
+
     parseNotEqualTest(#"\1"#, #"\10"#)
 
     parseNotEqualTest("(?^:)", ("(?-:)"))