Merge branch 'sk/userdiff-swift' into jch

Userdiff patterns for Swift have been added, with support for
Swift-specific constructs such as attributes, modifiers, failable
initializers, and generics.

* sk/userdiff-swift:
  userdiff: add support for Swift

Documentation/gitattributes.adoc

@@ -914,6 +914,8 @@ patterns are available:
 - `scheme` suitable for source code in most Lisp dialects,
   including Scheme, Emacs Lisp, Common Lisp, and Clojure.
 
+- `swift` suitable for source code in the Swift language.
+
 - `tex` suitable for source code for LaTeX documents.
 
 

t/t4018/swift-actor

@@ -0,0 +1,5 @@
+actor RIGHT {
+    let a = 1
+    // a comment
+    let b = ChangeMe
+}

t/t4018/swift-attribute-with-args

@@ -0,0 +1,7 @@
+struct View {
+    @available(iOS 13, *) public func RIGHT() {
+        let a = 1
+        // a comment
+        print(ChangeMe)
+    }
+}

t/t4018/swift-class

@@ -0,0 +1,5 @@
+class RIGHT {
+    let a = 1
+    // a comment
+    let b = ChangeMe
+}

t/t4018/swift-enum

@@ -0,0 +1,5 @@
+enum RIGHT {
+    case first
+    // a comment
+    case ChangeMe
+}

t/t4018/swift-extension

@@ -0,0 +1,5 @@
+extension RIGHT {
+    static let a = 1
+    // a comment
+    static let b = ChangeMe
+}

t/t4018/swift-failable-init

@@ -0,0 +1,7 @@
+class Bar {
+    init?(RIGHT: Int) {
+        let x = 0
+        // a comment
+        print(ChangeMe)
+    }
+}

t/t4018/swift-func

@@ -0,0 +1,5 @@
+func RIGHT(x: Int) -> Int {
+    let y = x
+    // a comment
+    return ChangeMe
+}

t/t4018/swift-generic-subscript

@@ -0,0 +1,7 @@
+struct Container {
+    subscript<RIGHT>(index: Int) -> Int {
+        let a = 0
+        // a comment
+        return ChangeMe
+    }
+}

t/t4018/swift-init

@@ -0,0 +1,7 @@
+class Foo {
+    init(RIGHT: Int) {
+        let x = 0
+        // a comment
+        print(ChangeMe)
+    }
+}

t/t4018/swift-inline-attribute

@@ -0,0 +1,7 @@
+class Service {
+    @objc func RIGHT() {
+        let path = "/api"
+        // a comment
+        log(ChangeMe)
+    }
+}

t/t4018/swift-modifiers

@@ -0,0 +1,4 @@
+public static func RIGHT() -> Int {
+    // a comment
+    return ChangeMe
+}

t/t4018/swift-protocol

@@ -0,0 +1,5 @@
+protocol RIGHT {
+    var first: Int { get }
+    // a comment
+    var second: ChangeMe { get }
+}

t/t4018/swift-struct

@@ -0,0 +1,5 @@
+struct RIGHT {
+    let a = 1
+    // a comment
+    let b = ChangeMe
+}

userdiff.c

@@ -362,6 +362,16 @@ PATTERNS("scheme",
 	 "\\|([^|\\\\]|\\\\.)*\\|"
 	 /* All other words should be delimited by spaces or parentheses. */
 	 "|([^][)(}{ \t])+"),
+PATTERNS("swift",
+	 "^[ \t]*((@[A-Za-z_][A-Za-z0-9_]*(\\([^()]*\\))?[ \t]+)*([a-z]+[ \t]+)*(func|init|deinit|subscript|class|struct|enum|protocol|extension|actor)[ \t(?!<].*)$",
+	 /* -- */
+	 "[a-zA-Z_][a-zA-Z0-9_]*"
+	 /* hexadecimal, octal, and binary literals */
+	 "|0[xX][0-9a-fA-F_]+|0[oO][0-7_]+|0[bB][01_]+"
+	 /* integers and floating-point numbers */
+	 "|[0-9][0-9_]*([.][0-9_]+)?([eE][-+]?[0-9]+)?"
+	 /* unary and binary operators */
+	 "|[-+*/%<>=!&|^~?]=|&&|\\|\\||<<=?|>>=?|\\?\\?|\\.\\.[.<]|->"),
 PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
 	 "\\\\[a-zA-Z@]+|\\\\.|([a-zA-Z0-9]|[^\x01-\x7f])+"),
 { .name = "default", .binary = -1 },