Merge pull request swiftlang#204 from dabelknap/composition-type

Add composition types

Author: allevato

Sources/SwiftFormatPrettyPrint/TokenStreamCreator.swift

@@ -1191,6 +1191,14 @@ private final class TokenStreamCreator: SyntaxVisitor {
     super.visit(node)
   }
 
+  override func visit(_ node: CompositionTypeElementSyntax) {
+    if let ampersand = node.ampersand {
+      before(ampersand, tokens: .break)
+      after(ampersand, tokens: .space)
+    }
+    super.visit(node)
+  }
+
   override func visit(_ node: DeclarationStmtSyntax) {
     super.visit(node)
   }
@@ -1397,10 +1405,6 @@ private final class TokenStreamCreator: SyntaxVisitor {
     super.visit(node)
   }
 
-  override func visit(_ node: CompositionTypeElementSyntax) {
-    super.visit(node)
-  }
-
   override func visit(_ node: ConformanceRequirementSyntax) {
     before(node.firstToken, tokens: .open)
     after(node.colon, tokens: .break)

Tests/SwiftFormatPrettyPrintTests/FunctionDeclTests.swift

@@ -122,6 +122,10 @@ public class FunctionDeclTests: PrettyPrintTestCase {
       print("Hello World")
     }
 
+    func myFun<S: T & U>(var1: S) {
+      // do stuff
+    }
+
     func longerNameFun<ReallyLongTypeName: Conform, TypeName>(var1: ReallyLongTypeNAme, var2: TypeName) {
       let a = 123
       let b = 456
@@ -135,6 +139,10 @@ public class FunctionDeclTests: PrettyPrintTestCase {
       print("Hello World")
     }
 
+    func myFun<S: T & U>(var1: S) {
+      // do stuff
+    }
+
     func longerNameFun<
       ReallyLongTypeName: Conform,
       TypeName