Add some keyword and key-path syntax to Swift lexer (#1332)

This commit adds support for the `some` keyword and `\.Type.variable`
key-path syntax to the Swift lexer.

lib/rouge/lexers/swift.rb

@@ -25,7 +25,7 @@ class Swift < RegexLexer
       )
 
       declarations = Set.new %w(
-        class deinit enum convenience extension final func import init internal lazy let optional private protocol public required static struct subscript typealias var dynamic indirect associatedtype open fileprivate
+        class deinit enum convenience extension final func import init internal lazy let optional private protocol public required static struct subscript typealias var dynamic indirect associatedtype open fileprivate some
       )
 
       constants = Set.new %w(
@@ -67,6 +67,7 @@ class deinit enum convenience extension final func import init internal lazy let
 
       state :root do
         mixin :whitespace
+
         rule %r/\$(([1-9]\d*)?\d)/, Name::Variable
 
         rule %r{[()\[\]{}:;,?\\]}, Punctuation

spec/visual/samples/swift

@@ -416,6 +416,7 @@ var `var` = 3
 
 // keypath
 let keypath = \Person.firstName
+var keyPath: KeyPath<String, Bool> = \.isEmpty
 
 // tuple destructuring
 let (t1, t2) = (1, 2)
@@ -432,4 +433,23 @@ funcWithLambdaArg { x in x + 5 }
 funcWithLambdaArg { $0 + 5 }
 funcWithLambdaArg({ x in x + 5 })
 
+func newView() -> some View {
+	ViewRegistry.find(\.MyView.name)
+}
+
+@frozen
+public enum Types {
+	case a, b, c
+	case d
+}
+
+func test(t: Types?) -> Bool {
+	switch t {
+	case .a?: return true
+	case .b?: return true
+	case .c: return true
+	default: return false
+	}
+}
+
 foo() // end-of-file comment